Spacers which we studied about is the secondary product of the concrete and it is applied on concrete structure. Therefore, securing equal or greater performance than concrete is desirable. Also, there is a tendency that concrete structures are strengthened. Therefore, reinforcement is used more and it is needed highly strengthened spacer. In this study, therefore, we would like to develop highly strengthened spacer which has crack resistance during construction. After this study, we confirmed that the spacer we developed has good crack resistance in construction.

According to the recent trends in the construction business have been actively booming both overseas plant orders and high-rise buildings orders. In addition high-rise building projects have being promoted or is actually under construction in Korea. Frame structure review which is the most consuming period on high-rise building is essential on that project. In this study looks for the currently form system and compares to those large system used in high-rise buildings.

The category for waterproofing is one of construction process most affected by falling-off in price competitiveness, construction quality, and material performance. Therefore, in order to select of waterproofing construction firms, it is necessary to consider Incorporating both price competitiveness and construction quality. In this article, I would like to analyze 10 Factors for Selecting using fuzzy-AHP model, including the survey of the waterproofing experts. This fuzzy-AHP model can be shown to calculate the fuzzy trigonometrical function to reflect weights for preference of 10 factors for the waterproofing construction firms. It was found from the result that waterproofing construction firms was searched order of priority for select by fuzzy-AHP model.

This study is to examine general roller and rotation in using self-adhesive waterproofing sheet. Using self-adhesive waterproofing sheet is very comfortable in a waterproofing construction site. However, In mechanical construction, self-adhesive waterproofing sheet occurred that problem for using. It induce many water leakage problem. So, We make Rotation Roller for to solve the this problem, and then Comparison with Physical properties of Self-Adhesive waterproofing sheet in applied General Roller and Rotation Roller.

According to develop urban area, the depth and floor area of basement tend to become deeper and larger. Excavation work for basement floor work is very important because its cost take 20% of total construction cost. Therefore, many studies of developing retaining wall system have performed for feasibility and safety in deep excavation work. In this study, new supporting system used high-strength pipe for retaining wall is introduced to reduce the construction cost and improve the safety and constructability by analyzing case study.

The process of building project for planning, designing, construction, maintenance, and waste disposal are related with each other. However, we have a difficulty for estimating building's LCC due not to be flexible each other. Therefore, we analyzed the boundary condition between the process of construction and maintenance, and analyzed the factor of segment. We also suggested the Link System for flexible relation.

The domestic construction industry recognize that review of design and construct-ability has the devastating effects. The way to take advantage of BIM for increase the possibility of discovered the design errors in advance are being discussed a lot recently. Since 2012, Public procurement published that the Turn-key project which is the more than 50 billion won in construction have to let the BIM-based design be mandatory. However, people expected the advent of BIM technology can resolve the existing design errors. But the situation is the connection of design stage and construction stage is very insufficient in domestic. Therefore, in this study understanding the types of design errors in construction phase. according the review of design errors before construction. Then can acceleration the application of BIM to improve the workability in a construction site.

The precast concrete column-beam structure, Green Frame, allows the main structural members such as precast concrete column and beam to be produced on the site, resulting in a reduction of transportation cost and the margin of plant. However, existing plywood from for in-situ production of precast concrete members has problems like putting in inordinate human resource, falling-off in quality and workability. To solve those problems, form system for in-situ production of precast concrete members shall be developed. In this regard, this study aims to analyze the structural concept of from system for in-situ production. The result of this study will use for development of form system for in-situ production.

Movable scaffolding has been used to work in high places. The scaffolding is economical and convenient to move to other places, but it has the risk of falling down. This paper proposes a fixed bracing system to prevent the falling down of a movable scaffolding, and evaluates its usability by making a small-sized model. Further studies of structural stability, safety, and economical efficiency is necessary to use the system practically.

BIM technology accomplished quantitative development being utilized in various disciplines. However, it is necessary to develop environment and requirement for qualitative improvement of BIM-based project in current transitional period of adopting BIM. The purpose of this study is to develop and apply of quality control requirement for improving the quality of BIM-based architectural design through case study. In particular, by focusing on BIM quality control and its relevant subjects, the minimum standards for BIM quality management are suggested. Also, BIM template is suggested to support the effective application of BIM-based architectural design.

Construction IT convergency proposes advanced management abilities of a construction project. Sensing data provided by various sensor technologies can be utilized for diverse management areas. This study analyzes required functions of sensors for implementing time, cost, safety and quality management, focusing on the ground works including excavation, pipe installation, retaining wall etc. Therefore, this study first generates essential management areas, analyzes cutting-edge sensor technologies appropriated for the areas, and finally proposes a matrix system that represents relationships between the management areas and sensor technologies, The proposed system is expected to reinforce construction management abilities by integrating sensor technologies.

High temperature / high pressure spray equipment using a conventional method, unlike spray polyurea adjustable pot life and yellowing caused by UV light and chemicals do not occur, or discoloration of Self-Leveling Type of rugged hand-polyurea resin for technology development is underway. This new concept of polyurea resin roller, brush, airless spray, and they installed easily using the unfamiliar labor, and curing time of approximately four hours to gain control of the glass because it is Pot. Construction, but does not like the spray polyurea resin, compared to the existing degradation of the adhesion strength is concerned. In this study, Self-Leveling Type Manual of polyurea resin adhesion strength of target deterioration Let's minimize problems by reviewing existing domestic and infrastructure long-term durability for long life of the facility is to obtain.

As a part of recent CO₂ emission reduction studies in the concrete industry with active use of concrete admixtures with low basic unit of CO₂ emission such as blast furnace slag (BFS), basic unit of CO₂ emission by SBFS was computed in order to assess CO₂ emission by reinforced concrete building with smart blast furnace slag (SBFS). In addition, SBFS concrete was applied to the subject building for assessment of CO₂ emission during material production step among construction steps. Life cycle CO₂ emission assessment on the subject building was classified into 7cases according to mix ratio of BFS and SBFS.

In this study, the CO₂ emission and economic efficiency of high-rise apartment houses were evaluated, and were analyzed as a way to establish database on the evaluation of environment-friendliness of high-rise buildings. To that end, standard of buildings to be evaluated were proposed through analysis of the designing guideline for high-rise apartment houses proposed by Seoul city, and CO₂ emission of the subject buildings were evaluated based on the characteristics of materials admitted into each building and the amounts of energy consumed during lifecycle period. In addition, the initial costs in construction stage and annual costs in operation stage were set as analysis parameters, and along with calculation of direct cost by the consumption of construction materials and energy, the costs of CO₂ emission were evaluated and analyzed. As a result, the CO₂ emission and economic efficiencies of high-rise apartment houses by construction stage and operation stage could be analyzed quantitatively.

This study was conducted as a part of database construction for development of CO₂ assessment system for concrete to assess CO₂ emissions and analyze characteristics of blast furnace slag manufactured in Korea through life cycle assessment method. For this, life cycle CO₂ emissions assessment technique for construction materials was examined. The entire manufacturing process for blast furnace slag was analyzed on blast furnace slag manufacturer in Korea for application of assessment technique. Life cycle CO₂ assessment was performed on blast furnace slag after classifying assessment process into raw material production step, raw material transportation step and construction material manufacture step.

This study is aimed at utilizing LCA processor with BIM LOD, eliciting the problems of the existing environmental assessment by constructing the database for environmental values of green buildings. For these objects, environmental load database of BIM construction material and evaluation process are presented, after matching BIM family based environmental load database which is available during evaluation stage, input-output tables and Korea LCI database to standard item code of public procurement service. It is a important factor in environmental assessment of building to develop database unit of standard item code for BIM and construction material. Thus, the results of this study are expected to provide basic data for improving effectiveness of construction through BIM based environmental load evaluation database. Furthermore, the provided environmental load database unit for construction material is considered to be available as basic information for BIM study by suggesting a processor connecting BIM with LCA and along with this, continuous examination on the connection process is needed.

PMIS has been progressed to signification of collaboration tool which knows the flow of information and facilitates communication between the project participants. However, research has actively been studied combining with BIM to solve this problem as revealed many issues in PMIS. The purpose of this study to analyze a trouble that arise when operating BIM-based PMIS and suggest about grafting Virtual Computing Technology and compatibility analysis on the alternative.

Work to repeat the work using the tool since many occupational diseases such as musculoskeletal disorders, such as occupational low back pain is increasing. To solve this problem, previous(or existing) studies for improving the environment of construction workers are working, but the previous study was lack of approach that applied to condition of construction field. Thus, the objective of this paper will analysis the Correlation of musculoskeletal disease which is caused by Working Hand and Working Type for workers. The results of this Research through a die to improve the work environment of workers and prevention of musculoskeletal disorders in order to prepare is to provide basic data.

A large-scale construction project relies much on the efficiency of construction equipment. Therefore, efficient and accurate measurement on the productivity of construction equipment is one of important task in the construction industry. Based on the motivation, this paper proposes a 11-axis composite sensor for an automatic measurement of construction equipment. A 11-axis composite sensor is composed of a gyroscope, geomagnetic and accelerometer sensor for the purpose of real-time motion captures of construction equipment. It is expected that the proposed system can save considerable time, effort and cost of measuring a efficiency of construction equipment.

In case of concrete, it should be deformed by many factors, such as explosive spalling, thermal strain and creep at high temperature. Structural fire design has been proposed to predict fire damage as national standard. It is general safer to use values obtained from tests of unstressed residual test in stead of stressed test. But most of thermal properties on concrete were conducted with normal aggregate. In this study, it evaluated mechanical properties of concrete with aggregate type and loading condition. we use normal and light aggregate to have different thermal properties. Also, we test mechanical properties to use Ø100×200 mm cylinder specimen according to target temperature and 0%, 20%, 40% loading.

The butt-joint system is widely used as the method of roof composite waterproofing system. However, there is stilll no objective research about proper distance, and proper structure associated with the performance in butt-joint system. In this research, we find proper distance and proper structure in butt-joint system through tensile strength test at joint, and comparative analyze with practical construction material of composite waterproofing sheet.

This paper is to investigate the engineering properties of the concrete incorporating different types of low heat generating binders subjected to various W/B. As expected, it is found that increase of W/B resulted in a decrease of hydration heat and compressive strength. It also showed that the application of high early strength and low carbon type mixture had favorable strength development at early and later age, while hydration heat showed rather higher than existing low heat mixture.

The purpose of this study is not only fixation of carbon dioxide using the cement-Paste solution's calcium ion by wet carbonating reaction but also quantitatively evaluate the possibility of storage technology of Carbon dioxide. wet carbonation is reaction of CO₂ injection by CO₂ reactor. As a result of experiment, the carbon dioxide is fixed, and high-purity Calcium Carbonate is eluted.

In this study, basic physical properties and color development of the black concrete depending on CASB-SP dosages are investigated. According to results, It showed that the slump and air contents of the concrete containing CASB-SP meet all requirements of concrete except when CASB-SP 5.0 % is used. It also showed that the more the CASB-SP is used, the higher the compressive strength becomes. On the other hand, It is found that if the CASB-SP 5.0 % is used, the compressive strength was reduced as the more CASB-SP 5 % is used. In terms of color, it was found out that the more CASB-SP is used, the darker the black becomes.

This study is to assess the differences between concrete having only one of fine aggregates such as crushed fine aggregates, sea sand and blast furnace slag in it and concrete having mixture of two kinds of those fine aggregates in it in order to find out how to deal with the lack of some aggregates. The findings are as follows. In terms of slump, the concrete containing sea sand and blast furnace slag has very low slump values while the concrete having the mixture of crushed fine aggregate and the other fine aggregates showed better workability. In terms of compressive strength, the concrete containing the mixture of two kinds of aggregates showed higher compressive strength. Accordingly, it is likely that the concrete containing the mixture of crushed fine aggregate, sea sand and blast furnace slag is better than the concrete with only one kind of fine aggregates in terms of the usability.

This paper is to compare the temperature history of the concrete using existing curing sheet and developed curing sheet made with double layered bubble sheet subjected to clod climate. Field application was conducted. According to results, application of developed curing sheet makes the temperature of curing house and concrete higher than existing curing sheet by about 3℃. This is due to the lower thermal conductivity of developed curing sheet.

This application plan is hasty prepared with the actual condition in which the majority is reclaimed by the waste with the marine and the polysilicon sludge, that is the main raw material of the solar pannel support, does. In this research, by using OPC and Fly ash, the applicability as the blending material of the polysilicon sludge was analyze and it tried to contribute to the waste reduction afterward. The replacement ratio of the sludge was set to 5. 10, 15, 20(%) with the experiment based on the based test result and the air flow rate, liquidity, flexural strength, and compressive strength was measured. The liquidity was reduced in spite of as the replacement ratio of the sludge increased and the air flow rate increased.

This study analyzed and compared the flowing and strength properties of mortar depending on the different fine aggregate replacement ratios and whether or not the mixing of PVA fiber was applied. blast furnace slag, red mud, and silica fume that are industrial by-products were used for the analysis. The findings showed that higher replacement level of fine aggregate increased air content while decreasing the table flow. In addition, in case of the compressive strength, Plain mortar and PVA fiber with the replacement ratios of 15% and 30%, respectively showed the greatest strength development.

RC structure which is located at shoreline has more serious damages compared with inland structure, because it is directly exposed to chlorine ion which is called incoming salt. In the transmission of incoming salt, differences in transmitted volume of incoming salts could occur according to the influences of local shoreline topography which includes surrounding weather conditions, types of building placements, obstacles of wind tunnel etc. And therefore, for the application of boundary conditions for durable offshore structure design against the salt attack, comparative analysis through wind tunnel test and fluid value simulation are executed in order to investigate the moving and adhesion process of incoming salt to offshore structure.

Recently outside insulation is applied on the building. Adhesion mortar and anchor are used fixing method of outside insulation. However, a research on proper Adhesion Strength is not performed. So outside insulation exfoliate from building in rainy with winds. Therefore, this research suggest proper adhesion strength about conjugation method of outside insulation. As a result, adhesion way using the adhesive mortar + anchor is best. And proper adhesion strength is over 1,065 N.

Recycled aggregate (RA) produced from demolished concrete waste can bring about several problems on concrete performance, when it is used as aggregate for new concrete. Because RA generally has lower quality than natural aggregate due to the residual cement paste attached on RA and various impurities. It is also very difficult to ensure that the quality of RA remains consistent, because generally RA is produced variously. Thus, in concrete recycling, it is extremely important to estimate the risk of the impurities which could affect performances of recycled aggregate concrete (RAC) focusing on the material flow of concrete waste and its recycling. This study suggests an evaluation result to expect the possibility of impurity mixing in RA production procedure. and suggests a risk evaluation model to expect the changes of RAC performances based on conventional data in Japan.

This study tried to present the appropriate replacement ratio of the recycled sand through the properties of the ternary system inorganic composite mortar according to replacement ratio change of the recycled sand about the natural sand through test verification. The flowing and compressive strength was degraded as the replacement ratio of the experimental result recycled sand increased. The appropriate replacement ratio of the recycled sand according to it was shown up less than 15%.

A policy for recycling waste concrete has been extensively studied, but it is still lacking to recycle and reuse as a cementitious powder, and the property has big different depending on the aggregate rates. In this study, the amount of cement powder according to the internal properties of the aggregate were mixed. From as a result, Concrete Powder to play inside the aggregate composition of the cement composition CaO rigs that causes loss of power and strength reduction due to rising real water cement ratio will affect large.

Lately, minimize of the heat loss and fuel consumption when heating so that suggested ways to reduce carbon emissions as a measures to reduce for increase of carbon emission and find a way to apply highly insulated concrete as the measures. In this study, as a comparative experiments on heat conduction of concrete with lots of porous, thermal conductivity of concrete using foamed, polystyrene beads, lightweight aggregates, air-entraining agent and concrete using crushed stone measure and thermal conductivity of concrete with lots of porous compare and evaluate.

This study was conducted to investigate the strength development of fly ash concrete using the strength development estimation for the ready mixed concrete for construction of nuclear reactors. The findings are as follows. First, the higher the curing temperature becomes, the shorter the setting time becomes. In addition, the compressive strength also increased as the curing temperature gets higher. The apparent activation energy derived from ASTM C 1074 showed 34.75 KJ/mol. The results of concrete strength estimation confirmed that Gompertz model formula has good accuracy.

The purpose of this study is to evaluate a defect in apartment buildings as review a safety investigation and consult a defect. As a result to compare a safety investigation to consult a defect, they are almost similar in spite of the purpose and the scope of evaluation are different. Therefore, it needs to establish a special and systemic system, and follow an organized effort about raising a consultant and improving an ability.

The productivity of the construction industry is lower than other industries. Modular system is suggested to enhance the productivity of the construction industry. Modular system is a construction method which installs units manufactured in factory on site. It enables to reduce the duration and improve the quality of the constructions. However, the construction technique applied to modular system has not overcome certain structural problems. To solve the problems and motivate the application of modular system, this study propose the hybrid system which use core to resist a lateral force.

The number of safety accidents of the construction industry is higher than other industries. To prevent the accidents from hazard factor, the employees are variously trained in avoiding an accident. Also many studies have been conducted to reduced the safety accident. But most of these studies are limited to institutional complements. This study proposes safety management improvement plan of safety management through case studies.

This study has been reorganizing a standard breakdown structure of temporary technique focused on construction site. For this, first of all we, the authors, reviewed features and present statuss of construction temporary technique, and could develop to the standard breakdown structure through studying a construction site and researching a delphi method. By using the standard breakdown structure obtained from this study, it is expected that the application of to information of construction business and plan to a schedule and a work.

The management for materials and inventory is one of the factors which are considered the most for profits of a business in almost all industrial fields. Resource procurement which occupies more than 40% of an overall construction cost has a strong relationship with profits of a business but it is regarded as a work for a manager rather than for a technician. It makes the importance of resource procurement relatively low and slows down the development of workings. As the construction project becomes more larger and complicated, effective management for materials are directly affecting the profits of a business. Therefore, this research works on finding an economical managing method for materials according to a characteristic of construction project based on accurately forecasted BIM data. Finding a reorder point by using BIM data which contains an accurate data for schedule and material enables a better management for materials and provides more accurate data on matters which were used to be determined by an intuition of a manager.

It has been passed around two decades since the CM is introduced in December 1996. And 20 years have passed. Construction Technology Management Act is the enacted of 1987, since Independence Hall fire in 1986. In the meantime, basic background and operational rather than the development of regulations that skewed had a voice of concern. Accordingly, Ministry of land is promoting a full-scale revision that Construction Technology Promotion law as switching to promote and support the necessity from Regulatory and management-oriented paradigm. In this paper, according to the Construction and Technology Promotion law amended in the course of doing business, was conducting research for drawn counterstrategy through SWOT analysis that was not the side of owner but CM company.

It is the important accurately to identify the needs of our customers in order to success the project. Requirements in the early stages of business is very abstract or not quantitative, and that will cause problems such as cost or schedule changes. Particularly many people are likely to prefer the early stages of the project, because the time of applying VE related cost savings is important. Owner's requirement analysis for project success in the VE process does not easy, and specific ongoing management of the requirement is difficult. Therefore, the analysis and the application of owner's requirements is limited in project process. The purpose of this study is proposed to the RFM technique to supplement the functional analysis on the basis owner's requirements analysis in planning a building project.

Exhaustion of fossil fuels and continued high oil prices, global warming, climate change and to respond to the development and use of alternative energy technologies is expanding rapidly throughout the world. Recently, character of domestic building is appearing by along with economic growth, high-rise, large size, congestion. For this reason, the amount of electrical energy used in a building is increasing. In this study, the applicability of PV modules that are used as roofing and efficiency analysis, and more from the building of BIPV modules built using the activation of alternative energy sources in Korea are aimed want done.

Although the order of Design-Build is being expanded by increasing construction scale and demanding hybrid function, the suitable regulation of the contracts is not settled. Design-Build is way by government because there are big construction of much government leading in contract relation high position occupy. So, case that prebendary's claim institution develops by litigation is very rare. But, recently Design-Build is magnified. So, these dispute factors is becoming visualization gradually. The contract system is needed to be consistent by international standard to deal with the problem. This study suggests the useful solutions in detail concerned with the main factor of change order claim by each Design-Build phases through practical sorting and analysis of the causes of Change Order-Claim.

The Fire growth rate(kW/s²) is significant impact on initial fire behavior in fire safety design of buildings. As a result of domestic existing combustibles, this study analyzed considering matters in techniques for calculating caloric values, and then made an investigation sheet. By utilizing written combustion sheets, the study could suggest a standard model at common houses and dense ones after getting caloric value information in dense ones. As a result, fire growth rate is experiment 1(0.01), experiment 2(0.0048), FDS(0.0072), MATSUYAMA equation(0.0144).

Domestic construction materials market was about 65 trillion won and it occupied 45% level of total construction cost by 2007. In addition, due to the recent rapid rise of crude oil and iron ore price, fluctuation of raw material cost has a great influence to the cost of construction industry. This means that smooth performance is closely related to construction materials. And among them, because of high putting rate of metal materials, it can be seen that the fluctuation of metal material prices is an important variables. So in this study, for the pre-study to analyze the impact of metallic material prices to construction cost, the researcher analyzed a causal relationship between metal material prices and construction cost.

Facility Management (FM) is a project phase to maintenance and to increase the qualities of product which is planned on the design phase and ensured on the construction phase. In addition, since the approximate time occupied in operation and maintenance phase is the longest from construction project as total approximate cost is about 85% of whole the project, it could be managed and realized primarily. The information of facility is not created on the specific point of project, but it might be created on the whole process of subject project widely. Thus, as the information could not be lost and it can be delivered into computer aided facility management system, it is necessary to manage the facility information. This paper proposed the necessities and the problems of BIM-based data interoperability on the Korean construction projects.

Using green construction equipment, there are some disadvantages like increasing construction costs and delaying the schedule. Despites of disadvantages, green construction equipment is necessary for decreasing environmental load in construction industry. Therefore, this study proposed checklist for green construction equipment selection. For the checklists, criteria of the checklist were drawn by literature review in the aspects of contractor and a survey was performed in order to measure weights of the criteria. When a contractor choose the green construction equipment, this checklist can support an objective decision-making.

A number of construction projects tied to the concerns and decision-making is also very complicated. In addition, more than any other industry, is inherent in many risk factors. In the course of the construction project on risk factors that exist in the early stages of project risk factors to predict in advance and prepare a project by shortening the construction period and project cost as you can to maximize performance. In this study, I proposed risk management processes and how they are used in web-based schedule risk in the process of change management system, and between 3D CAD, 4D CAD taking into account the linkages, risk management strategy process in the BIM environment.

With the increasing public concerns on sustainability in construction industry, a variety of standards for green buildings have been developed and implemented. However, most of their criteria are not adaptable to evaluate environmental performances of construction activities. Besides, the great part of existing studies are focusing only on energy consumption and CO₂ emissions, overlooking the impact of pollution sources which occur intentionally in the construction phase. In this study, indicators and their importances are investigated to assess the overall environmental performance of construction activities.

According to the analysis report of construction fall accident, situation not installed safety facilities caused the largest of disaster in temporary structure. Therefore, actionable measures will be needed identifying the installation of safety facilities immediately. In this study proposed plan by the safety facilities to effectively visualize, supervision can be easily for reduce fall accident. This system can be used BIM and augmented reality technology by combining in the field in real-time. Through this study, safety facilities management is improved and expected to prevent a accident.

According to the increase of demand of the deteriorated building. The interest of the building's maintenance is continually increased, so studies about how to increase building's stability & prolonged life span are increased. This study's purpose is to maintain building's function, so we suggest a protocol type system of UI to estimate reasonable planning of demand of repair & replacement and to distribute budget.

Recently, there are growing interests in building LCCO₂ Assessment to reduce carbon emissions. However, existing methods of assessment system include inefficiency in the process of CO₂ calculation requiring considerable data input. Therefore, the purpose of this study is to develop an efficient building assessment system appropriate to material production in construction stage. To that end, quantity input technology was limited to data mapping. Also quantity calculation based on work breakdown structure and item codes consisted of hierarchical structure that is based on facet classification were analyzed. As a result, connectivity links of quantity calculation and CO₂ functional units through item codes for data mapping, and assessment system including calculation and database parts were developed.

In recent years, the number of high-rise buildings has been on the rise. As buildings have become larger in scale, significantly different issues related to their construction and maintenance have emerged. In addition, the automation and mechanization of the cleaning work for the curtain wall, one of the most frequently-performed tasks in building maintenance, is required as a fundamental measure. For this reason, a guide-rail type cleaning robot system is emerging as one of the measures in response to external factors, including gust. The major objective of this study is to propose an economic feasibility forecasting model and to apply the a building facade cleaning robot which is now under development.

Recently on Value Engineering(VE) and Life Cycle Cost(LCC) social interests is increasing. The government Turn Key, BTL projects and public works projects, such as VE and LCC Analysis on the value and economic analysis is mandatory. And accordingly the VE and LCC analysis is underway for the various studies. However, there is a problem existing in the LCC analysis. Worth the cost varies according to the flow of time. However, the real interest rate during the LCC analysis of buildings in calculation time for interest rates and inflation are not considering the value of the flow. In other words, a few years using the average value of the deterministic analysis method has been adopted. These costs for the definitive analysis of the cost of an uncertain future, unforeseen changes resulting hazardous value. In this study of the last 15 years interest rates and inflation targeting by using Monte-Carlo Simulation is to perform probabilistic analysis. This potential to overcome uncertainties of the cost of building a more scientific and LCC Estimation of the probability value of the real interest rate is presented.

The purpose of this study is introduction of social and economic benefits of environmental improvements of Korea green road certification system. Focus of Evaluation Criteria is possibility of quantification on environmental improvements. Proposed evaluation items is noise, air pollution, water quality, ecological and green spaces, waste, and space resistance. The results of this study is expected to be used to support of Green Roads Rating System in korea.

Although work-efficiency of construction machinery is a critical factor for estimating its workable-quantity per unit time, the coefficient figure table presented in the Poom-Sam that is used for Construction Cost Estimation of public sectors in Korea is very subjective for practical usage. In order to suggest objective work-coefficient table for a Tub Grinder, domestic and overseas documentary records were investigated and on-going construction sites were also visited. The research found that the table can be revised by means of detailing down by several factors. The research will be the foundation for applying the rapid development of Construction Equipment and technology to the appropriate cost estimations and the ground work of related studies.

This study is concerned with the VSTUD shear reinforcement that it can be installed easily in filed as product at the factory and seismic performance can be achieved. The method of study is as follows. first, we researched constructability and economy of existing method. Secondly, we made specimen and were examined structural performance tests in order to verify the performance of the shear reinforcement. As a result, developed SL shear reinforcement increased in shear strength and stiffness of reinforcement, structural safety is judged to be increased.

In this study, coupler on the safety of meeting the requirements and construction and economy to satisfy the number of parts to minimize an LK-DK coupler has been developed, affordability existing reinforcing bar joint, welded joint, mechanical joints, compared with a favorable one to the understanding, and also facilitate the construction and logistics, etc. I've found that there is no additional pay because the amount of product performance through the tensile test after test, if commercialization is expected to be greater ramifications.

Korean government has developed and implemented a five-year master plan in order to enhance construction technology competitiveness and its level of development. However, without detailed assessment of past plans it is not likely to retain feasibility and sustainability of a new five-year plan, This study analyses adequacy of the 4th five-year master plan in terms of evaluation strategies such as indicators, methods, targeted performance through benchmarking various construction policies utilized by developed countries. In addition, this manuscript provides the basis structure and critical factors for establishing future construction policies or plans.

Recently, as part of an effort to realize the low-carbon green growth, the research to measure the degree of greening about the road facility with United States as its center was performed. In addition, the Green-road certification is enforced and applied. In this study, we would like to examine the applicability of the green-road certification to domestic road to promote the settlement of green-road certification system to contribute the related industry development for the green technology development and application and spread in the roads sector.

As a separate project unit, the domestic construction policy evaluation is independently evaluated and managed by different involvements, so that it has been difficult to have a consistent policy evaluation to be performed. In this paper, thus, it is aimed to give an overview of the evaluation system and issues of domestic construction policy and suggest strategies of a improved evaluation system by a comprehensive benchmarking of construction policy evaluation system of Japan. The implications of this paper will serve a basis of improvement of a better construction policy evaluation system in Korea.

The BIM(Building Information Modeling) introduction of the construction and maintenance at the design phase through the life cycle of the building until it is destroyed, I will bring big changes in the process. If you are building a small action by a variety of variables difficult to manage on-site construction, but, BIM remodeling of the building by applying a small improvement in the quality of imported building and construction delays, such as design changes or re-construction by removing the elements of economic 04 to make. Since the early stages of applying BIM to complement the introduction part, but the future seems to lead to changes in the built environment, academics and practitioners of the construction industry seem to have an active research.

In this study, it was investigated early age strength generation of low cement concrete with type and addition ratio of hydration accelerator obtaining fundamental data for the application in construction field.

Concrete has cracks from shrinkage that necessarily result from in hardening process. Shrinkage-reduced concrete developed for crack reduction was utilized at a sample construction project. As a result, it is confirmed that crack initation ratio was remarkably reduced when compared to the case of normal concrete utilization. Additional sample project is supposed to use delay joints as well as srinkage-reduced concrete. Subsequently, the result will be reported. The greatest factor which affects in drying shrinkage is unit quantity of water. However, there are a lot off difficulties in field supervision because proper measuring means is not presented in present standard. Therfore, problems depending on ready-mixed concrete concrete companies should be improved by preparing the related standard assoon as possible.

The establishment of the technology for evaluating friction resistance and pipe pressure and the relation of the fluid characteristics and pumpability of concrete is essential for the evaluation of concrete pumping performance for high speed construction of super-tall building. So, this study focuses on quantitative evaluation of concrete fluid characteristics and surface friction resistance under the change of concrete mix proportion and pumping condition. In this study, we measured the rheology of concrete and pipe pressure and surface friction characteristics when pumping. And, relations between the rheology characteristics of concrete and pumping performance was investigated by experiment. As the result of the experiment, high regression between the surface friction and pressure gradient was confirmed. And, prediction model to evaluate the friction resistance coefficient and pipe pressure reduction coefficient was suggested.

Recent the free-formed architecture is smearing as a trend with the development of the digital equipment and technologies. The development of new method based on digital technology is required for the free-formed structure,, because the conventional construction methods are limited to shorten the construction period and to ensure the construction quality. Particularly, the development of the new method for the free-formed concrete structure is important. In this study, the developed method of the T-shape lightweight steel fabricated using CNC can control the geometries of the free-formed concrete structure based on the digital design. Also, new method is effective to ensure the precision of the construction and economic than the conventional construction methods.

In this study, the following conclusions are drawn. First, the Inorganic terazzo tile flooring and LCC (Life Cycle Cost) analysis showed that the sum of the total cost of 150,304 won Inorganic flooring, terrazzo tile flooring minerals won 186,202 to 35,898 won, compared to 8.22% analysis of the cost savings that have been appearing. Second, if the color chip has a unique and elegant sentence patterns, beautiful and high-strength bonding and that the crack resistance was investigated.

Over the years, the recovery of the domestic construction market, which does not appear on the reverse, but rather due to a surge of construction materials cost of the construction sector is experiencing greater difficulties. Cement raw materials in the manufacturing process, if some of the waste recycling, cites quality control for products and measures for the thorough management is needed. In this study, three companies of the past four years in the production of cement against doejin physical performance test results conducted yearly and seasonal trends by analyzing changes in the years to review the cement for cement to utilize as a basis for management points is.

This paper presents basic study to develop high performance concrete for concrete filled tube with addition content of steel fiber. In this study, all mixtures was added to nylon fiber (1.5 kg/㎥) and steel fiber was mixed by 0, 20 and 40 kg/㎥ respectively. To evaluate the property of high performance concrete was used to various test methods which were slump flow, air content, U-box test, O-lot test and L-flow(to 300 mm, 500 mm). Also, compressive strength test was measured by ages.

Emissions of CO₂ occur during the production of cement manufacturing process. During the production of clinker, limestone is mainly calcium carbonate, is heated to produce lime and CO₂ as a by-product. It has a major problem, CO₂ uptake is not considered in concrete carbonation, just focus in CO₂ emission. This study is to develop a simulation model for CO₂ uptakes in concrete structures based on carbonation reduction coefficient considering finishing materials. CO₂ uptakes unit of concrete cubic meter is calculated by CO₂ emissions unit of concrete materials and usage of concrete materials in mix proportion. From the simulation result, CO₂ uptake ratios is 2.04 percent in carbonation models of concrete structure during 40 years.

To prevent energy waste in buildings used heat insulator. Heat insulator materials can be classified inorganic and organic. The organic material is be toxic gas emission, when a fire occurs. And it has lower water resistance. The inorganic material is heavy and worse thermal performance than organic materials. This study focused on thermal conductivity and density of inorganic foam material for using industrial by-products materials.

Steel method compared with conventional aluminum truss construction materials as the biggest difference, aluminum truss method by using an aluminum material construction of the existing steel truss compared with the welding operation is omitted, as the air operations will be reduced by about 40% do not need skilled workers in the existing portion of each tube and cost 11,233 to 13,173 won/㎡ cheap it was found.

In recently constructed building, It has become fashionable again that the heavy external skin system such as a Stone Finished Envelope. There are Squared Steel Pipe Methods, C-Shaped Steel Pipe Methods, and Aluminum Beam Methods in the structure of a heavy external skin system. The Aluminum Beam Methods is often misunderstood as a Plane Truss Structure, but this method is not appropriate to be called to a truss structure but a beam methods. The Aluminum Beam Methods is the most Eco-friendly methods in terms of Quality assurance, Efficiency, Safety, Construction period, Durability, and Recyclability. And this Methods is also very appropriate in considering the point of Energy conservation, Waste reduction, Long-life architecture, Replacement parts, Environmental protection, Public efficiency, and Building demolition.

The analysis of microstructure is essential to understand the material behavior such as shrinkage, strength, and permeability. In this study, three different easy-to-apply specimen preparation methods for the mercury intrusion analysis were chosen, and their effectiveness in removing pore water and thus impeding further hydration was evaluated. As a result, it was found that the direct freeze-drying was the most effective among the three methods.

As industrialization progresses is rapidly growing, the city of density and temperature is rising successively. It leads to the status of environmental issues. It is needed to develop process of planting concrete block using by Eco-materials for replacing to he existing rooftop light soil that imported. In this study, developing the process of planting lightweight block is researched on using applications of 6 Sigma technique. It makes process object improve standard by using statistical method. Also, there are suggestion that it is optimum mix design conditions and affection of experimental factors in matters of developing planting concrete block for rooftop greening.

The exiting studies on the strength prediction by maturity method is mainly focused on concrete using OPC, meanwhile the study on the concrete mixing blast furnace slag powder (BFSP) is insufficient. The purpose of this study is to investigate the relationships between compressive strength and equivalent age by existing Maturity functions, i.e., Nurse-saul function Arrhenius function. This study also compared and examined the strength prediction of concrete mixing BGSP using ACI model and Logistic Curve prediction equation. Therefore, it is intended that fundamental data are presented for quality management and process management of concrete mixing BFSP.

In this study, it carried out measurement experiment Ca(OH)₂ and chemically bound water to verify Ca(OH)₂ and chemically bound water prediction model out of hydration model of cement incorporating blast furnace slag. It compared and analyzed prediction results using prediction model with measurement results of Ca(OH)₂ quantity using thermogravimetric differential temperature analysis and chemically bound water quantity using electronic furnace. It agrees well experiments results with prediction results.

In this study, strain properties of high strength concrete using light weight aggregate which is widely used in recent years are evaluated. For these purpose, thermal strain, transient creep were measured in prestressed condition as 0, 20, 40% of specimen strength at target temperature with 60MPa specimens which was using normal and light weight aggregate. As a result, light weight aggregate is more advantageous for the control of strain than normal aggregate because of its low thermal expansion.

With regard to the carbon reduction that has become an international problem, we have examined the effects of compressive strength of the ground granulated blast-furnace slag mortar with the curing temperature. Also, we evaluated the mechanical properties of steel slag powder produced during the steelmaking process in order to examine the possibility as admixture.

Recently, as the national policy of green growth is promoted, construction field also makes an effort to reduce CO₂ gas released when producing cement continuously. In other words, as the method solving environmental pollution and resources exhaustion, lots of mineral material compounds such as blast furnace slag powder which is industrial by-product, fly ash, red mud, etc. are examined to bo used as the substitute good of cement Therefore this study is to investigate the hardening characteristics of alumino-silicate inorganic binder using red-mud used as a accelerator of industrial by-product such as fly ash and blast furnace slag powder according to curing temperature. As a result, it is effective to use red-mud as the accelerator of inorganic binder with other additory accelerators.

The purpose of present study is to examine the long-term strength improvement of hardener-free epoxy-modified mortars with steam curing. As a result, strength improvement of hardener-free epoxy-modified mortars is markedly improved with increasing of air-dry curing period. This is improved by markedly increase the degree of hardening of the hardener-free epoxy resin in the epoxy-modified mortars with additional air-dry curing period.

Recently, preparing countermeasures about energy depletion and CO₂ emission progressing rapidly is considered as an urgent problem not only in domestic country but also in international countries. Among this, the requirement for the comfort development of in door environment is increasing according to housing culture and life environment changing. Thus, it is required urgently to save building energy and develop fusion technology maintaining comfort of indoor environment. Recently, energy-saving ways in saving heating and cooling energy by latent heat and thermal storage is considered significantly. In this study, keeping up with the times, thermal performance analyzed. Also, this study has the aim to draw materials for evaluating usefulness and efficiency.

This study discussed the applicability of double layered bubble sheet(BS) to the concrete for retaining wall to verify the insulation effect as well as prevention of condensation. The BS was applied to the surface of retaining wall, which is contacted with ground. Temperature profile was monitored since placement of concrete. As expected, the application of BS helps the concrete keeping favorable heat insulating, preventing condensation.

This paper is to investigate the effect of waste cooking oil(WCO) on carbonation resistance of high volume fly ash and blast furnace slag concrete. WCO and paint were applied for carbonation resistance materials. As expected, the application of WCO to the concrete help it reduce carbonation depth remarkably, regardless of mixture types. This may be due to the fact that WCO makes the capillary pore block by activating saponification. It is found that the degree of carbonation reduce due to WCO is much higher than the case by Paint.

This study try to finding the self-detergency performance of adherent pollutant on the mortar surface by using the developed silicate based antifouling coating material. Developed coating material coated on the surface of mortar test piece and after 30 minutes, over layed already coated mortar surface. After 7 days, the surface is polluted with crayons and oily magic marker. After 24 hours, contaminated area was wiped out the water. From the result of self-detergency performance test, it is concluded the developed material could be used as a detergent the contaminated concrete surface.

This study attempted to the effect on the physical performance of silane coupling agent on solventless epoxy-based concrete surface finishing material for parking floor. Tests were carried out in accordance with KS F 4041 and KS F 4937. The results of compressive strength, flexural compressive are 95.6N/㎟, 25.4N/㎟ and after wheel moving load testing, average abrasive depth is 0.96mm, these results satisfied the quality standard of KS F 4041, KS F 4937. As conclusion, this study confirmed that the silane coupling agent greatly effected on the physical performance of solventless epoxy resin.

According to increase of the waste concrete occurrence, recycling has being important more and more. This study is to recycle the waste concrete powder, which is occurred in dry-process during recycling of construction waste. We have tried the waste concrete powder to apply as the replacement of the silica powder in cement extruding product. As a result, it is satisfied that the autoclave cured pannel of 50% replacement ratio of waste concrete powder staisty the level of the flexural strength of 14MPa stipulated by "KS F 4735 Extruding concrete panel" was the same thermal properties as base specimen.

In this study, Analyzed the effect of the change in RFA and RCA substitution rate on the concrete containing BS bonding materials but no cement. The findings are as follows. First, the fresh concrete has less slump value and air contents as more RFA and RCA is used. In case of hardened concrete, as more RFA and RCA are used, the higher the compressive strength of concrete becomes. Especially, the compressive strength of concrete which used recycled aggregates only is found to be 2.2 times as high as that of concrete using natural fine and coarse aggregates only. But if the concrete is to be used as the structural concrete having the compressive strength of 13.8 MPa, the alkaline materials and some cement are required to be added.

In this study, it was evaluated about shrinkage properties of high strength concrete according to poly mix fiber and moisture evaporation condition. As a results, When concrete was mixed with poly mix fiber of spalling control, it reduced effect of shrinkage independent of the evaporation conditions of unsealed and sealed.

Recently, environmental pollution and global warming and greenhouse gases are increasing, because Efforts to improve are continued throughout the world. As part of the resource recycling industry has become an important research area. In the field of waterproofing industry, focus on the resource recycling is growing, due to serious resource depletion and sharp price. Therefore, in this research on the resource recycling such as reclaimed rubber and rubber waste is enable and these eco-friendly materials are applied high adhesive flexible non-exposed type self adhesion compound waterproofing material was measured eco-friendly performance and field application was evaluated.

Repair and strengthening is necessary to extend the service life of existing buildings. Polymer-modified cement mortar (PCM) has been extensively used as a high performance material particularly for finishing and repairing works in concrete building because of itsexcellent adhesion, waterproofing, resistance to chemical attack, and workability. As PCM contains organic polymer, it is necessary to clarify its properties at high temperature under fire, on which sufficient data are not available. This paper evaluated the burn-up characteristics of polymer-modified cement mortar with cone calorimeter test, non-combustibility test and flammability test with experimental parameters such as the types of polymer, unit-polymer content, polymer-cement ratio and thickness of the specimen.

Recently, high-rise building projects have been in the spotlight in South Korea. Curtain wall construction, as one of important operations in the high-rise building projects is composed of various, entangled and complex unit processes that require a systematic planning to prevent unexpected delays. A schedule simulation technique has been used for deriving more efficient planning and accurate performance measurement. However, the simulation technique has difficulty in collecting actual data and in applying data fluctuations during construction. Thus, this paper suggests a concept model of Modular Simulation Model(MSM) that overcomes such limitations of traditional simulation technique based on curtain wall operations.

This paper presents a system called a Cash-flow based Construction Scheduling Optimization (CfSO). The existing CPM is biased on schedule and cost management. For a profitable and successful project management, the cash-flow which occurred actually by contractual conditions should be considered in the project scheduling. Therefore, this study provides a method to estimate the amount of a cash-flow occurred periodically by integrating the terms of contract into scheduling. The proposed methodology is implemented as a system prototype in Microsoft Excel. CfSO helps a site manager as a decision-maker to establish a optimized project scheduling and decide profitable contractual conditions against a construction owner.

Construction Materials are the key elements determining the quality of buildings. The major purpose of this study is to provide basic data analysis for leveraging domestic construction material information systems. The study implements a comparative analysis by categorizing the construction material information systems into several detailed areas. The research results specify the limitations of current construction material information systems and derive required research areas for practical applications throughout a construction project life-cycle.

Many efforts have been made and many tools have been developed in order to manage construction projects by a smart device such as a smart phone and smart pad. This research proposed a method to manage construction schedules via a smart device using Flash. The interactive and graphic property of Flash enables a field manager to manage schedules easily and efficiently. A prototype was implemented by Adobe Flex Builder, and it applied a sample network in a smart pad. Further studies would develop network diagrams such as CPM(Critical Path Method).

The construction industry in the local areas business as the archetypal local one is effectuating industrial production, create employment and so on to perform a significant part in keeping local economy also reviving sluggish economy. The construction stagnation in market may cause severe economic depression in local which leads to having a crippling impact on local constructive industry, in terms of the phenomenon is on the interrelation between the local construction industry and local economy, with regard to local economy which is not covered by firm based industries is wield strong influenced over by construction industry. The object of this study is to research possible improvement factors on the preferential basis by only companies' efforts, therefore the policy of government or local self-governing body in support may be unnecessarily involved after grasping faced practical problems at regional construction companies from analysing the present condition of local construction marketplace and companies.

Although installations and usages of gang-form that has advantages of preventing fall disaster, the serious disasters from gang-form occur every year. This research focused on the continuous prevention of disasters in construction of outer wall of apartment working site through step by step safety management worker's checking table. The result is the worker's checking table for safety management in apartment gang-form works, through safety guidelines case studies, interviews with safety management experts and then extracting a check list.

International oil prices is the world's leading macroeconomic indicators. Rising international oil price has been worsening. profitability of construction company including material cost as well stagnation in housing market. Thus, according to fluctuations in international oil prices has cost index need to see any change happening there. in this study, 2000 to 2011 interest rates, exchange rates and oil price fluctuations in construction cost is to compare the impact.

Since 1980, rapid social and economic development due to increased plant construction has led to a plant dormitory in a short period. In recent years, by the advent of the durability of dormitory remodeling is a critical need. However, user requirements due to the lack of owner's budget do not reflected. As a result, users have complained about the scope of construction, and construction stakeholder in accordance with the budget efficiency of the complaints have decreased. In this study the remodeling requirements in the planning stages is proposed for the remodeling process. In addition work type and element can select a range of construction worksheet are proposal.

Because steel frame has own characteristics as easy to work and structural safety, it is being increased application by the trend of construction industry has been more higher and larger in today. However, steel frame works have potential problem, so fundamental solution is needed for preventing serious accidents. Recently, self-supported steel joint for enhancing safety is developed in Korea, but this system has some limitations as convenience of work, retainment of consistent productivity. For complementing this limitations, we developed the new system named Automated wire control machine. This study is performed productivity of steel frame work by new system. The basis data for analysing productivity is collected from field test.

The validity of the numerical model used in the program is established by comparing the prediction from the computer program with results from full-scale fire resistance tests. Details of fire resistance experiments carried out on reinforced concrete slab, together with results, are presented. The results obtained from experimental test indicated in that the proposed numerical model and the implemented codes are accurate and reliable.

Structural steel has been used as a primary materials to columns and beams since 1960's in Korea with an advantages of excellent of load-bearing capacity and design flexibility, and faster construction. However, if the steel columns made of structural steel exposed to fire the load-bearing capacity is going down steadily and finally reach to collapse. Therefore, building regulation requires fire resistance according to building occupation, scales. The fire resistance can be evaluated two categories. One is prescriptive method that is based on building regulation, specification and so on and the other is performance-based fire engineering method. The latter can be designed based on scientific and engineering consequences. The easiest evaluation way using the fire engineering design is comparing to the limiting temperature and maximum temperature calculated based on heat transfer theory. If the limiting temperature of a column exceeds the maximum temperature of it, the column can carry the load during the fire. Therefore, the database of limiting temperature is very essential for evaluation of column. In this paper, to build the database of column made of rectangular hollow sections 8 fire tests with loading were conducted and the relation between the limiting temperature and the applied loads showed in reverse proportion.

In modern Construction Industry, as accumulation of capital and improvement of technology skills, buildings are becoming higher and more enormous, also the portion of steel works has been increasing. In addition, it is necessary to predict the optimum level of construction cost in a reasonable way. The composition of construction is direct construction cost, indirect construction cost and so on. However, it is not enough to study about indirect construction cost rather than direct construction cost. In this study, the state of productivity and indirect construction cost are analyzed in the steel production. As a result, the productivity and ratio of indirect cost in steel plant by inserted per 1ton are suggested.

As a rahmen structure, the connection among columns of Green frame is divided into three types such as sleeve, coupler (column pre and post installation), and bolt. The bolt type consists of six types according to steel frame shape and each type has different constructability, safety, structural performance, cost, and quality. Therefore, the analysis of comparison among the types is necessary. The objective of this study is to analyze the characteristics according to the shape of six bolt types to select the appropriate connection of Green frame. The results of this study can be used as a basic study for indentifying the characteristics of steel frame on site applying bolt type connection of Green frame. In addition, this study can be applicable to compare and analyze the performance and constructability of six bolt types in detail.

Green frame is combined by structural steel and reinforcements of Green column and beam and unified by cast-in-place concrete. However, when upper reinforcements penetrate structural steel hole, the execution is difficult due to interference of joint and a rib of deformed reinforcements. Therefore, the objective of this study is to propose the reinforcement tools to improve productivity of precast structure connection construction. The reinforcement tools proposed in this study can be helpful to improve constructability, safety, duration, and cost comparing with conventional reinforcement method since unskilled workers can deal with reinforcements easily.

This study introduces a method for computation of process and operation gap in the specific construction operation(i.e., RC frame construction applying a block-grouping scheme) using CYCLONE-based simulation modeling and analysis technique. Since uncertainty of construction environment exists, a thoughtful production planning is required to effectively deal with a risk resulting in schedule delay in advance. This study presents the concepts of a time delay occurred in a process level and operation level in a operation model, and a method of measuring gap-times in each level while the simulation progresses. It helps a site manager to decide how many segmentation in a construction block is suitable for eliminating unproductive time-delays under the constrained resources (e.g., laborer, equipment). A case study presents a network model representing a three segmented RC frame work, and result obtained from the simulation experiment.

The Korean construction market and housing policy have been increasingly focusing on supplier. As opposed to houses in private areas, Apartment House using the common infrastructure such as elevators, electrical facilities, heating system and hot water supply system need joint management. Their management usually depends on the resident cooperation or outsourcing. On this study, I investigated the level of satisfaction of Apartment House residents and its managing personnel, the conditions of its management, and analysed the important factors which influence the degree of residence satisfaction with respect to its maintenance and management.

Korea construction techniques are confident that the world's best work, but construction worker is the level of the worst working conditions. Korea Construction Industry Improvement of facilities for the advancement of the field workers need more than anything else. Improved facilities for field workers in the construction sector is responsible for a large shaft and substantially promote the welfare of workers in the field and contributed greatly to the morale and will help to improve housing quality can be expected. Earlier status of construction workers and facilities is considered an urgent need for improvement.