Proceedings of the Korean Institute of Building Construction Conference (한국건축시공학회:학술대회논문집)
The Korean Institute of Building Construction
- Semi Annual
Domain
- Construction/Transportation > Construction Engineering/Materials/Management
2015.11a
-
Environmental load reduction and sustainable development one of the study's research into the available material is discharged, remove the coarse aggregate and fine aggregate from waste concrete and utilizing the remaining cement fine powder as an alternative raw material for limestone is the main raw material of cement developing playback cement that was the purpose. Physical over existing research and chemical quality was confirmed was evaluated for durability by promoting carbonation test, research studies on the durability evaluation insignificant. As honipyul within the aggregate differential lung fine powder increases carbonation resistance performance've found that increased sharply and, S0 showed fairly similar to the OPC. Therefore, the development within the technology research to separate fine aggregate discharge fully differential and waste fine powder is determined to be the development and use of the playback durability of the cement with the carbonation levels corresponding to the OPC if made.
-
This study is to development of inorganic insulation material using by-product materials. The organic material is due to 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. In this study, cullet and fly ash were used as basic materials in order to secure a recycling technology of by-products which was mostly discarded and reclimed, and measure of physical properties of Inorganic foam material.
-
The purpose of this study is to investigate the expansion of alkali-activated geopolymer mortar containing reactive aggregate due to alkali-silica reaction. In addition, this study is particularly concerned with the behavior of these alkaline materials in the presence of reactive aggregates. The test method included expansion measurement of the mortar bar specimens and geopolymer compressive strength test. Major results that alkali-activated geopolymer mortars showed expansion due to the alkali-silica reaction. geopolymer mortars is safety for the expansion exhibited less than 0.2% at 14 day.
-
Waste Concrete Powder will be generated during the manufacture of construction waste as recycled aggregate Waste concrete. The main component of the waste concrete Powder is a silica-based composition 51% SiO2, waste concrete cement-based composition Al2O3 10%, CaO 26% component are contained. The material is silica sand of PHC piles should experiment by replacing the Waste Concrete Powder. The compressive strength results are as follows. 25% when the Silica was replaced 32.5Mpa, when 50% have replaced 43.4Mpa, when 75% have replaced 45.3Mpa was measured. Compared with the non-replaced test sample it appears that the strength increases. Therefore, it is determined that the practical use of the PHC piles by replacing silica via this experiment is possible.
-
This study analyzed sulfate resistance of strongly acid-resistant inorganic binder based on industrial byproducts. According to the study experiment, compared to OPC mixture, the mixture of high acid-resistant inorganic binder had excellent chemical resistance against 10% H2SO4 solution. In the case of ordinary portland cement, its sample with 28 days of immersion had severe corrosion on its mortar erosion part, and thus external appearance was damaged greatly, and compression strength decreased by around 57% and more.
-
Carbonation is the results of the interaction of carbon dioxide gas in the atmosphere with the alkaline hydroxides in the concrete. in other words, of the hydrates in the cement pastes, the one which reacts with readily is Ca(OH)2, the product of the reaction being CaCO3 and which decreases the alkalinity of concrete. Consequently, RC structure is deteriorated due to steel corrosion in concrete. As the importance of maintenance of reinforced concrete structure recently has emerged, the attention of durability of structure has been increasing. There are many studies about durability decline especially due to the carbonation. In order to study carbonation progress after surface repair of carbonated concrete, each carbonation penetration velocity from different repair materials of concrete structure is compared through the experiment of carbonation accelerating CO2 concentration to 100%. As carbonation infiltration progress is predicted through this study, the counterplan of service life evaluation will be prepared on selection of repair materials of concrete structure.
-
Natural stone causes environmental pollution when it is collected and processed. Also, it is hard to make consistent products. Therefore, this study focuses on the artificial stone with waste porcelain to replace natural stone. The flexural strength and compressive strength are lower according to the replacement ratio of blast furnace slag in the result of experiment.
-
In the case of concrete recently manufactured with a concrete mixing truck, although aggregate and cement are used as the main ingredients, from a costs savings perspective, low quality aggregates are processed and used as concrete aggregate. In the case of these low quality aggregates, the unit volume and unit binder weights are increased for manufacturing, and due to this problems such as dry shrinking of the architecture and economic infeasibility have arisen. Therefore by changing the aggregate material and the unit binder weights that are currently being distributed, this research analyzes the influence on concrete.
-
In this research, by examining the influence that high quality fine aggregate and low quality fine aggregate have on the strength of concrete through tests, the manifest strength of concrete according to high quality fine aggregate was reviewed. The results showed that compared to low quality fine aggregate usage mixture, the unit volume to achieve the same liquidity decreased and accordingly the W/B also decreased therefore increasing the strength of concrete, and as high quality fine aggregate was used, it is determined that there can be improvements to the economically feasibility of usage mixture and improvement in durability etc.
-
For the facility using explosive gas, it is very important to use anti-explosive structure. Therefore, using FRC of high stiffness should be used, but the research on actual application under the construction conditions is not sufficient. Hence, in this research, based on the case study on application of FRC for anti-explosive structure, the strength characteristics of FRC with combined fibers were evaluated comparing between before and after the pumping.
-
To secure fundamental materials for the performance change in concrete structure damaged by fire, this study analyzed SEM and XRD of hardened cement depending on high temperature conditions. As a result, at more than 200℃, SEM and XRD were not observed because of dehydration of Ettringite; at more than 500℃, calcium hydroxide was rapidly decomposed; at more than 700℃, calcium oxide was found; at 1000℃, the highest peak point appeared.
-
The purpose of this study was to investigate the compressive strength property into concrete using rice straw ash.. In an effort to evaluate the effects of rice straw ash as mineral admixture, rice straw ash was mixed with cement at the mixture ratio of 0, 5, 10 and 15% relative to the cement weight. When the mixture ratio of rice straw ash was 10%, the highest compressive strength was observed, while the strength tended to decrease when the mixture ratio of rice straw ash was 15% even if it exhibited higher compressive strength than the plain. And it was observed that compressive strength of concrete containing rice husk ash was a similar a compressive strength of concrete containing silica fume.
-
Due to the big fire in Uijeongbu, the status of construction, fireproof materials and structural method were examined to prevent fire propagation through outside insulation parts of urban living homes. Through research and experiments, the following results were obtained. It was confirmed that outside heat-insulation wall method was used in a large number of urban living homes which were made of materials and structures spreading fire easily.Through experiments, it was revealed that lightweight plate material, as a fireproof material, can save the cost as well as the period of construction and obtain more than 30 minutes of evacuation time which is twice the maximum evacuation time.
-
High velocity impact of projectile generate local failure such as penetration, scabbing, perforation on concrete. It has been reported that local failure is affected by such as nose shape, mass of projectile. In this study, comparing and weighing the impact failure properties of concrete by high velocity impact test that using spherical nose and flat nose type projectile. As a result, It was considered that scabbing of Flat nose projectile reduced more than spherical nose projectile by dispersion of impact force.
-
Depending on the industrialization, construction market has grown buildings are based on concrete will continue to increase. But the problems of environmental pollution come to the fore with the indiscriminate use of concrete and rapid development. In addition, carbon dioxide(CO2) in the process of producing cement being emitted a large amount of has been caused a serious problem of environmental pollution. This trend is being actively conducted research to reduce the use of cement. In this study, eco-friendly materials, such as flats, Blast-furnace slag by mix and cement review the mechanical characteristics of the mudflats eco-friendly cement mortar to reduce the usability of the review were seen as a green building material.
-
Recently, introduction of Advanced water treatment facilities has been increasing due to serious domestic water pollution. Ozone is a strong oxidizing materials in the advanced water treatment facilities. However, due to such a strong oxidation, Ozone eroded waterproofing/corrosion on the concrete surface and caused performance degradation. Therefore, in this study, permeability experiment of metal spraying system by concrete surface treatment was conducted.
-
Recently, there has been a rapid increase in demand for lightweight walls for their use as interior partitions, as types of structure have gradually changed from shear wall structures to column structures or flat plate column wall systems. The lack of resisting force in lightweight walls is found by measuring the depth of dents in impact resistance tests, but it is not a direct factor of impact resistance. However, in the user's position, dents of over a certain size are clearly a factor that visually reminds the need for repair. In this study, we reviewed relative methods of assessment of the need for repair based on the visual means of determination (sensory test) on the dents on lightweight walls. Dents were found to stand out starting from depths of about 4mm, and the depth of roughly 5mm was found to be the criterion for determining the necessity of repair for men, while it was 4mm for women.
-
For the purpose of reducing defects (cracking) in topping concretes cast as artificial greening layer base, synthetic macro fibers were mixed. The flexural strength of synthetic macro fiber mixed topping concretes was tested via comparing its performance with current topping concrete. According to the results of the testing, topping concrete with adjusted mixing ratio after mixing with 1kg of synthetic macro fiber showed approximately 15% higher flexural strength compared to the current topping concrete.
-
The concrete aggregate generates carbon dioxide in production but its demanding is gradually increased in accordance with the depletion of natural resources. Therefore we evaluated compatibility and basic physical properties of Silicon manganese slag generated in iron production as an applicable concrete aggregate. In our test, the silicon maganese slag shows 2.8g/㎥ of density in 10mm of maximum particle size similar to a natural aggregate, and its absorption rate was 0.3% similar to the electric furnace slag. Unit volume weight and ratio of absolute volume was respectively 2,001㎏/㎥ and 51%. Strength properties of Silicon manganese slag will be evaluated with further studies and experiments.
-
In this study, spalling property were evaluated from concrete with compressive strengths of 30MPa, 90MPa, 180MPa, applied with fast heating condition(ISO-834 standard heating curve) and slow heatign condition(1℃/min). As a result, the spalling property of concrete was shown differently with compressive and heatign rate. And It could be separated three as non spalling, surface spalling and explosive spalling.
-
Recently, the large amount of sulfur is globally generated by the development of the petroleum refining industry every year. In this study, without the use of the sulfur with a high melting point used in the previous studies, the modified sulfur mortar with addition of a melting point of about 65℃ were tested to determine their distribution and strength properties according to the mixing method and curing conditions. This study is a test to find out the Density, Absorption and Table Flow of the modified sulfur and general sulfur. As result, general industrial sulfur flow was lower, showed a high absorption rate.
-
Recycled aggregate used in a site is strong alkali due to calcium hydroxide attached on its surface. Accordingly, many environmental problems arise. Therefore, as basic research to reduce pH of recycled aggregate, this study tries to reduce the strong alkalinity of recycled aggregate by using mixture solution based on sodium phosphate and ammonium chloride. As a result, original aggregate has the strong alkalinity of pH 11.23, whereas pH of recycled aggregate immersed in mixture solution decreased as more mixture rate increased, and mostly pH 9.8 or less was found.
-
Recently, by-products from concrete industry are generated in large quantities because of urban redevelopment. Accordingly, waste concrete powder(WCP) inevitably generated in the course of crushing, screening, and separating the waste concrete also show high emission and be increasing gradually, but which is mostly buried with waste concrete aggregate. This is a basic research to increase the value added utilization rate of WCP. We have examined strength characteristic of extruding panel with WCP, depending on the curing methods. The result of study shows similar strength to the base specimen in autoclave curing condition. And in autoclave curing condition, the specimen with WCP of 20% and 30% satisfy the target strength of 14MPa.
-
In this study, the concrete in which the hybrid fiber with different volume and rate was intermixed in high fluidity concrete. However, Fiber Ball is frequently caused by the decrease in the dispersion of the fiber. The research has been conducted primarily study of single fiber or hybrid fiber, such as different length of single fiber. Therefore, we investigate the mechanical properties of concrete was mixed with a combination of various fibers been produced domestically. Its purpose being to provide basic data for evaluating the impact hybrid fibers on the fluidity of concrete.
-
As the result of uniaxial compression strength test on the CLMS mixing BFS and SS with BFS 4000, it required to determine the desired strength through increasing unit quantity of cement in mixing process because of dramatic strength deterioration of strength according to increasing replacing rate. In this study's result, regardless of differences in fine aggregates used, in order to get uniaxial compression strength in the scope exceeding criteria of minimum strength for applying to the field, the most reasonable combination was to mix replacing BFS with fineness of 6000 in 30%. For the CLMS mixing BFS and SS, in order to improve flow ability by securing quantity of minimum unit and to repress bleeding rate with securing uniaxial compress strength considering the field applicability, regardless of differences in fine aggregates used, to mix BFS over 6000 in 30% was most effective.
-
In this research the processing method of Desulfurized Plaster is changed to cyclotomy, 0.3mm sieve analysis and 500℃ heat exposure, and by changing the mix rate of the binding agent to 0~20%, it was applied to mortar that used natural aggregate and blast furnace slag for testing. The test results showed that the sieve analysis and high heat exposure of the flow and air volume increased according to the increase of mixing rate of FGD while the cyclotomy decreased. The setting time accelerated as the mixing rate of FGD increased, and the compression strength increased to its maximum when the mixing rate of FGD was right around 10%, and especially showed a high trend with cyclotomy and sieve analysis.
-
In this research the processing method of Desulfurized Plaster is changed to cyclotomy, 0.3mm sieve analysis and 500℃ heat exposure, and by changing the mix rate of the binding agent to 0~20%, it was applied to mortar that used cyclic aggregate and blast furnace slag for testing. The test results showed that the flow decreased in the order of cyclotomy, high heat exposure, and sieve analysis according to the mix rate of FGD, and while the air volume decreased for cyclotomy, it was shown to have almost no effect on sieve analysis and high heat exposure. The setting time accelerated as the mixing rate of FGD increased, and the compression strength increased as the mixing rate of FGD increased and especially showed a high trend with cyclotomy and sieve analysis.
-
In recent years, the accidents in construction projects are continuously increasing due to their complexity and variety. However, few studies have been conducted regarding the risk prediction model and the database of risk assessment in construction projects. To address of these issues, the objective of this study is to analyze the accident causes by using insured claim payouts of insurance companies. First, the descriptive analysis of accidents causes is conducted according to scheduling rate, season, and total construction costs. Second, the correlation analysis is conducted between accidents causes and total construction costs. In the future, the risk assessment model can be developed to quantify the accident causes in construction projects to estimate claim payouts of insurance companies.
-
In this paper, to prevent overspending of the CM Fee, Agent CM for the normal work-oriented, Willing to separate order model being used in the construction, using a multi-national grouping Go to offer the right company, a number of groups according to the appropriate CM Fee setting is aimed to suggest a reasonable basis. This paper does not use the domestic point of order characteristic of the model, and using a different theory of affinity grouping projection method is presented. The main disadvantage of the domestic order model because it is a contractual relationship, the contractual relationship as unified as possible by the most reasonable way of construction and construction capabilities and commercialization agreement upon the ability of companies also expect to be very helpful. The grouping by using the multi-order construction of the separation problem of the increase and thus the management object construction type administration was to solve the problem.
-
As construction projects have increased in size and height recently, lifting accounts for increasingly greater portion and tower cranes are used more frequently. At present, the selection and arrangement of tower crane are depend on the experience of experts. However, since the number of experts is fairly limited and a database for tower cranes regarding lifting capacity, operation properties, rent, etc has not been widely employed, tower cranes are often not effectively selected and arranged which can cause cost overruns and delays in the lifting work. To address such issues, this study attempts to perform a basic study for development of automatic arrangement algorithm of tower crane using drawing recognition. If relevant database is established and the algorithm suggested in this study is refined more systematically, even beginning level engineers will be able to plan tower crane arrangement in a way comparable to experienced experts.
-
This study compared and analyzed the job importance that site managers perceived by dividing the study scope into customized and expansion remodeling projects and deriving the job descriptions from previous studies. As a result, a total of 7 construction stages and 53 job descriptions were derived. As job importance in customized remodeling projects, removal and demolition works were the most important, followed by preliminary survey, and repair and reinforcement works. In addition, as job importance in expansion remodeling projects, preliminary survey is the most important, followed by civil engineering work, and repair and reinforcement works. It is considered that the job importance of the remodeling projects derived in this study will contribute to improving their job efficiency in the future.
-
Traditional External Insulation Finishing System(EIFS) is applied to apartment construction by performing structural framework and insulation finishing work sequentially. Separate execution of the three works increases construction cost and duration. Concurrent construction method of EIFS, which performs framework and insulation finishing work simultaneously, is introduced in order to solve these problems. However, the introduced method is exposed to the risk of construction delay caused by bottlenecks due to interacting processes and resources. Therefore, this paper presents a simulation model suitable for estimating work productivity of the concurrent construction by considering predecessor and successor processes to optimize resource allocation and minimize construction delay.
-
Construction period is longer than the non-disclosure in civil construction of apartment house. And this process is intensive at the beginning and end of construction. Because this project management expertise is required. Nevertheless, subsidiary work(Working avoid a tendency of advanced technician, Frequent turnover and employment contracts, etc.) management attention of construction is at a lower level. Because of, there are the bad factors(trial and error, finish degradation, etc.). Therefore, this study analyzed Hindrance Factor of quality control on apartment complex construction work and presented importance of civil construction engineer's role. Also, forms of civil construction engineer, Performance experience and technical Strength of apartment complex construction was investigated for the construction. To this end, It analyzes the relationship between forms of civil construction engineer, Performance experience and technical Strength of apartment complex construction and Construction of evaluation as required by Construction Technology Management Act.
-
For the past three years, the importance of automatic research has been increased. It was proved in previous research that the number of conducted research using 'Database' technique was the largest, but the amount of increase was the largest in research on 'BIM'. In consequence, it is predicted the research on 'BIM' will become a center of automation in construction. Therefore, the purpose of this paper is to examine trends though classifying into each construction phase and developed extent of techniques related to professionalization and integration with other techniques within a range of 'Automation in Construction Journal' which has the biggest level of awareness in construction field.
-
Recently domestic youth unemployment rate has increased continuously. The cause is due to construction recession. As a result, the youth unemployment rate was approximately 8.0% in 2013. In particular, graduates of civil engineers and architecture engineers are difficult to find a new job. Major construction companies also prefer new employees rather than career employees. Therefore, the employment rate of construction-related university graduates is continuing decline. Accordingly, construction and technical engineers will be aging. Therefore, this study was looking for ways to promote the overseas expansion of young construction engineers. And this research has suggested the ways which young engineers can find a new job through improving the system.
-
In construction industry, management of construction factors such as cost, schedule, quality and safety is the most important key for delivering successful projects. According to the Smart Market Report, a magazine specialized in construction industry, recently said 'Off-site Prefabrication' is a significant trend related with construction productivity in global construction industry. It is a kind of practice shift from On-site to Off-site. A lot of general contractors in oversea have been using 'Multi-trade MEP Ceiling Rack Prefabrication' method for getting benefits such as decreased cost & schedule and increased labor productivity. Thus, in this paper, critical management factors at each phase from design to installation was derived by researching case studies. Forwardly, it can be a basic guideline for applying Multi-trade MEP Ceiling Rack Prefabrication in Korea construction industry.
-
With the government's support for new and renewable energy, photovoltaic equipment has rapidly been supplied. However, compared to supply rate, maintenance has not supported enough and relevant research has not much conducted. Therefore, the purpose of this study is to analyze maintenance effectiveness of photovoltaic equipment. What is the most important in maintenance effectiveness is a rise in power generation. It was estimated that if photovoltaic equipment for detached houses is maintained well, power generation increases by 4.0% at least, and by 6.5% on average. As a result, it was analyzed that it is necessary to maximize the effectiveness of the government's budget investment through well maintenance of photovoltaic equipment for detached houses.
-
BIM has been a reliable construction project management tool to handle various kinds of construction information generated in the facility life cycle. To take these advantages, researchers have been promoted numerous studies in a residential, a commercial, and an educational facilities with a large number of on-going projects. However, despite running as the role of essential energy supplier, power plant related BIM research is relatively insufficient than others. In particular, due to the extending of the facility service period and the requirement of the complicated construction project management for 'overhaul' and 'repowering' in the power plant maintenance phase, the needs for using BIM have been increased gradually. For using BIM based maintenance, it is needed to consider an information collecting methods and necessary to develop an appropriate breakdown structure to share information. Therefore, 'EBS' is produced by reviewing the previous research related to BIM and analyzing the repair activities in the maintenance phase. Proposed 'EBS' must be useful not only a judgment between capital expenditure versus revenue expenditure but also appropriate maintenance strategies development for property management.
-
Remodeling of apartment houses has been increasing recently and residents have chosen to extend the balcony along with the legalization of balcony extension in apartment houses. Balcony extension provides residents more space, however, it has been investigated that balcony extension increases construction cost, heating and cooling cost and decreases sound insulation performance. Therefore, this study focuses on developing a decision making index for residents in remodeling required apartment houses. The suggested methodology involves surveying actual residents, survey analysis by AHP and decision model development using logistic regression analysis.
-
Recently, As the high rise buildings have been demanded due to the rising current of land price, the permanent drainage method have been applied during and after the construction as a way to reduce the buoyancy acting on the bottoms of the foundations in the basement. This method has brought about the consolidation subsidence of the ground and turned out to be the problems of sinking hole and foundation re-settlement. The representative methods to be used for extending the life cycle of the existing building structure which is tilted by the foundation re-settlement or differential settlement of the foundation can be divided into the building structures reinforcement and soil reinforcement. The purpose of this study is to analyze and present the application example of steel pipe pile method to extend the life cycle of the six -stories building tilted in a soft ground.
-
A defect dispute surrounding an apartment building is in constant trouble, a defect consulting is necessary that objective and impartial for solving a defect. The defect dispute about a defect lawsuit is conducted in the order that filling of lawsuit, consulting order, defect inspecting, estimating a repairing cost, writing a consulting report, submitting a consulting report, and decision by court. Of these, a step of defect inspecting is extensively investigated an occurred defect that each defect index and type from each part and place. At this time, it is collected of many data and created many information. For this, it need to organize and manage. The study is a modeling of field investigation work process that second phase of defect inspecting step. A literature study is defined a work until level 2. This study is defined the work until level 3 to 4. In addition, the modeling can do for using a job name, a place to job, a job to do, and a person concerned about defect consulting case. The modeling is expected a contribution of improving a defect consulting process and systematizing a judgment standard.
-
Recently, Incidence of natural disasters are growing gradually. The need for a monitoring system for maintaining the structural integrity of the high-rise buildings against extreme weather events such as typhoons, earthquakes is increasing gradually. One of the most important features in the tall building is to guarantee structural safety during the structure's life time. Structural monitoring technologies might be needed to manage structural safety and to protect human life.
-
This study was performed for application of Structural Health Monitoring system of Jamsil Lotte World Tower. Axial stresses of mega column and core wall are measured in the past 29 months for axial stress monitoring and evaluating predicted self weight. We use the midas gen program(FEM analysis program) with construction stage analysis mode to predict axial stress. 8 mega column axial stressmeters are installed at 21st floor and 4 core wall stressmeters are installed at 38th floor. Measurement data was obtained without creep and shrinkage effect.
-
Building construction education requires training and experience. While there have been many means of education, virtual reality (VR) can be applied as a complement for building construction education. Considering the characteristics of building construction education, interactive content based on VR technology is expected to raise the effectiveness of traditional education. This research conducted a survey to examine the applicability of VR technology to building construction education and provided basic information by prioritizing work types for educational content.
-
This paper aims to identify patterns in users' requests for facility management (FM) services in higher education facilities. We analyzed data collected from 309 service request forms, made available via a department office and an enterprise resource planning system, at a private university in Seoul between May 2009 and February 2015. We found that the number of user requests were the highest in September and October. Requests for electronic and communication (E/C) services outnumbered those for architectural services and mechanical and plumbing (M/P) services. Repair requests for doors and windows were the most common under architectural services; repairs for air-conditioners and radiators were the most commonly under M/P services; and installation of electrical outlets, telephone wires, and internet services were the most sought-after E/C services. Maintenance requests were received every three months, while repair requests were received every six or seven months.
-
Significant amount of bottom ash has been produced in the power plant located at southeast region of Korea, but those were abandoned in the pond site without any treatment. In these days, there is a strong move to enforce environmental regulations to protect surrounding nature, a lot of pressure is given to the power plant industry to remove hazardous chemicals from their waste material before landfill or site storage. The overall objective of this research is to separate hazardous chemicals from the bottom ash, and use it safely as sustainable construction material. In this specific study, magnetic separation of bottom ash was applied, and used as a fine aggregates to make mortar specimens. According to the results, it was found that the use of bottom ash decreased 28-day compressive strength. However, using non-magnetic bottom ash provides best results in terms of thermal conductivity, showing strong possibility to be used as heat insulating material.
-
Significant amount of bottom ash has been stored in the pond site of Hadong coal power plant located at southeast region of Korea. In order to address strong environmental regulation that is going to be enforced in the near future, it is necessary to consume waste bottom ash stored in the pond site in a sustainable manner. In this research, the chemical and mineral characteristics of various sized bottom ash samples from Hadong coal power plant were analyzed using XRF, XRD, and particle size analyzer. According to the experimental results, the chemical compositions of bottom ash was slightly changed in terms of Al and Fe content. As the size of the bottom ash increased, cristobalite was observed as a result of crystallization. The mineralogical composition and its size distribution of powder type bottom ash indicated that significant amount of fly ash is included together with small sized bottom ash.
-
This study is an experiment about what affects the compressive strength by using a reducing agent (PNS based admixtures) to play cement using the cement paste based Waste Concrete Powder of waste concrete, which accounts for more than 60% of construction waste around the latest domestic and international It was. Securing the replacement of cement with Waste Concrete Powder and, by varying the admixture was to compensate for the low absorption of liquidity and obtain a fine powder. And the experiment was conducted with a constant water cement ratio and aggregate usage for the purpose of lowering the water cement ratio promoting strength development. When substituted with the experimental results of 0.3% based on 3 ~ 28 days as strength 36Mpa exhibited the highest strength.
-
With an increase of concrete buildings as result of rapid industrialization, Remicon sludge, which is a strong alkaline construction waste, should be neutralized to prevent damage to a natural environment, and the cost of the neutralization processing is increasing as well. Accordingly, this study investigates the mechanical properties of cementless concrete which is processed with recycled water and industrial byproducts in order to determine the possibility of re-using sludge, recycled sand, and gravel which are contained in recycled water.
-
Layered Double Hydroxides is known as a hydrotalcite-like material. It is a type of anionic clay with planar structure. It is composed of layer structure which is able to exchange anion between two layers which includes divalent ion and trivalent ion. Therefore, layered double hydroxide is applicable for eliminating harmful heavy metals and anionic substances which exist in the concrete. Because it is also able to be used as catalyst and has high possibility of utilization, It is getting an large amount of attention recently. In this study, an analysis on the structure of the layerd double hydroxide (LDH) which is possible to bind the anion was carried out.
-
In this study, fresh state properties and mechanical properties of low slump concrete which is applied to road pavement have been evaluated by mixing modified sulfur. As results, influence of mixing modified sulfur on the workability was low. Also, compressive strength, and flexural strength tend to decrese with increasing addition rate of modified sulfur. However compressive strength, and flexural strength of modified sulfur concrete were equivalent with that of plain concrete.
-
There is high possibility of steel corrosion on the reinforced concrete exposed to marine environment by chloride ion penetration. And it show a big difference of concrete durability under conditions of splash zone, tidal zone, and immersion zone. Therefore, in this paper, half-cell potential and chloride ion penetration depth was measured to evaluate the durability of slag concrete by marine exposure experiment. As a result, SC70 specimen showed no steel corrosion, regardless of the marine exposed conditions. Also, a deterrent effect on chloride ion penetration by replacement of slag in tidal zone and immersion zone could be confirmed.
-
This paper is to investigate the effect of poor quality aggregate source used in Korea on the mixture proportion and strength development of the high strength concrete fixed at 450 kg/m3 of cement contents. For aggregate kinds, good quality crushed stone from KS certified manufacturer and low quality crushed stone from non certified construction field are used. For fine aggregates, river sand, land sand, sea sand and mixed sand are also used. It is found that the use of low quality aggregates resulted in an increase of water demand considerably due to poor gradation of aggregate and excessive fine particles. Test results indicate that the use of low quality aggregate also decreases the compressive strength compared with that of good quality aggregate.
-
A Experimental Study of Mechanical properties in mud flat mortar mixed with High-range Water reducerSince concrete has evolved to the development of the quality and performance there currently being used civil engineering, as the most important material in the construction sector. But the discovery of alternative building materials and indiscriminate use is negligible. So that is the situation facing the shortage of natural aggregate. Accordingly, this study reviewed the mechanical properties by replacing the aggregate through the mud flat of eco-friendly materials and analyze the usability by adding a high-performance water reducer for promoting workability.
-
Fracture behavior of concrete subjected to dynamic loading is affected by loading rate and strain rate. In this study, compressive strength properties according to strain rate of fiber reinforced cement composites by rapid loading with 500Ton rapid loading test machine was analyzed.
-
In this research, to evaluate the influence of using non-KS aggregate on concrete performance, the engineering properties of normal strength concrete were assessed depending on the KS aggregate and non-KS aggregate from various sources in mid-Korea. From the experiment, when the non-KS aggregate was used, low compressive strength was achieved with increased water-to-cement ratio caused by increased unit water due to high absorption rate of the non-KS aggregate.
-
Demands for the replacement materials of cement have been increasing due to social problems such as CO2 reduction and exhaustion of resource. Recently industrial by-products, for example GGBFS and fly ash, have been used as an admixture. However Studies on POFA have been insufficient. POFA, which is used in this study, was obtained from burning of palm oil shell and husk from a southern part of Malaysia. In this study, early compressive strength and porosity of cement mortar with POFA are measured, and appropriate fraction of POFA is 10%. In terms of porosity, POFA is used as a filer in mortar. Later, activity index of POFA and long-term experiments are needed.
-
Recycled aggregate is not used for structures because of negative awareness of quality. for improving the negative awareness, a concrete structure was built with 100% recycled aggregate and monitoring mechanical properties and durability was conducted. As a result, It was observed that mechanical properties and carbonation of structures with 100% recycled aggregate were fine.
-
Because of the high-rise and bigger building structure, high strength concrete's demand was increased. However, chemicophysical property of concrete is changed by high temperature. Therefore, this study evaluated on spalling properties of 80MPa high strength concrete with fireproof coating. The result, when complex fireproof coating spread on concrete, it has good fire safety that was thinner than single fireproof coating spread on concrete.
-
Recently, a number of problems due to the CO2 emissions are occurred. Therefore, it is a movement to restrict this activity. The research is being carried out steadily for recycling waste concrete from the cement paste based fine powder, which accounts for over 60% of construction waste as a recycled cement. In this study, the conclusion was obtained as a result of the research conducted, and then, replacing the main material of cement concrete to solve the above problem by reducing the amount of cement used Waste Concrete Powder. The more concrete results page replacement ratio of fine powder increases, the flow value of the concrete is lowered, the strength was remarkably reduced when the page Concrete Powder.
-
These days, as the usage of explosive gas is increased, the demand of safety of explosive gas is increased. As a suggestion of protection against the explosive gas, the research on application of fiber-reinforced concrete has been conducted. In this research, therefore, to evaluate the constructability of anti-explosive concrete, the engineering properties of the FRC after pumping is studied.
-
In this research by examining the influence that low quality aggregate has on the strength of concrete through testing, the lowering of strength according to use of low quality coarse aggregate was reviewed. The results showed that when using low quality coarse aggregate, due to the quality of aggregate a high volume of units was required, and this caused the compression strength to be lowered. In conclusion it was confirmed that if the low quality aggregate was used as is without mix correction this would lead to faulty construction and if the aggregate was corrected to about 60 kg/m3 mix correction, this would lead to an economically infeasible concrete mix.
-
This study analysed compressive strength and the expansion characteristic to utilize a high volume mineral admixture mortar for a aerated mortar and a plastering mortar. In this experiment, the result shows that the compressive strength gain was satisfactory in case that WR was replaced within 5%. Also, the difference between WR1 and WR was insignificant. It shows that the drying shringkage properties at large was showed being satisfactory generally compared with Plain when WR was replaced, but the effect was not significant.
-
The use of the cement and increased with the recent development of the construction industry. If the cement is the environmental problems caused by generating a large quantity of CO2 and the production process. Accordingly, this study is the test to determine the sulfuric acid and hydrochloric acid resistance properties of the Light weight matrix product of blast furnace slag-based light. A result, the compression strength of the sulfuric acid and hydrochloric acid immersion showed alower strength than the Plain.
-
Hwang, Eui-Chul;Kim, Gyu-Yong;Choe, Gyeong-Cheol;Yoon, Min-Ho;Lee, Bo-Kyeong;Lee, Young-Wook 139
The purpose of this study was to evaluate existing compressive strength equation with concrete exposed to high temperature by ultrasonic pulse velocity. As the result, original compressive strength equation is proper only for compressive strength of normal concrete. Therefore, an accumulation of experimental database of concrete exposed to high temperature is necessary for proposal of new compressive strength equation. -
This literature study is focused on the improvement of lightweight concrete in perspective of foaming agent. Lightweight concrete is the cured concrete as putting required amount of foaming agent to slurry which is a mixture of a certain amount of cement, sand, and water. It has lower density than general concrete, because foaming agent disintegrates numerous bubbles evenly and independently. Thus, it is capable of lightening the weight and great for sound absorption and insulation, In foreign countries, studies for structural lightweight concrete mainly of tunnel grouting and weight lightening of heavy structures are going along actively. Domestically, exterior panel and ALC blocks are alternatively used for flooring. Therefore, this research consider improvement of lightweight concrete in perspective of foaming agent with foundation study.
-
In this research it was attempted to analyze the general engineering properties of low cement mortar according to the type of setting accelerator and substitution rate, when 1% substitution rate for setting accelerator was used a high rate of compressive strength manifestation was shown and that the WS-10 type setting accelerator was appropriate. For the rate of change of length, when 3% substitution rate for setting accelerator was used, it was shown that due to initial expansion the shrinkage compensation was not significant, and when taking into consideration strength and shrinkage, 1% of WS-10 was shown to be appropriate.
-
When using non KS aggregate muck pile in general, compared to when using KS aggregate, when obtaining an identical slump a high unit quantity of water was confirmed, and when designing the concrete mix the compressive strength of concrete decreased due to an increase in W/B. Therefore because the use of non KS aggregate decreases the liquidity, strength and durability etc. qualities of concrete from an overall performance point of view, there is a need for the used of KS aggregate and when using aggregate that does not adhere to KS standards, it is determined there is a need for appropriate concrete mix design and care.
-
Exposed type waterproofing PVC sheets installed on structure rooftops are subject to changes in physical properties after longterm exposure to sunlight. Particularly when consideration the rotational movement of sunlight over the day through the course of the sun rising from the east and setting in the west, in the case of flat roofs the amount of UV ray the the surface of the PVC waterproofing sheet receives may be even throughout, but in cases of slanted rooftops the sunlight exposure may be uneven across the surface. In this regard, this study examines the effect uneven sunlight exposure on the exposed type waterproofing PVC sheets installed on slanted rooftops.
-
Structural beam plays a key role to carry the applied load on the floors. And then the beam have to sustain the applied load and its load-bearing capacity in fire situation. In this study to know the fire resistance performance of long span beam made of a submarine structural steels, an engineering method is used using mechanical and thermal properties of structural steel at high temperature.
-
Concrete parking slab is often deteriorated severely after winter season because of concrete's freezing and thawing phenomenon. In this study, some methods to improve resistance against freezing-thawing is experimentally tested.: 1) concrete strength, 2) air content in concrete, 3) saw-cut effect and finish material. After experiment, in case of no finishes, 24MPa concrete with 4% air content is tested best result in terms of relative elastics modulus among testes ones. In case of concrete with finishes, all specimens are improved regardless of finishes compared to concrete with no finishes. Improvement degree compared to no finish is as follows : Polyurea > Resin-mortar > hardener and the number of improvement degree is 5, 4, 2% respectively. Further work is required considering construction site condition such as gaining water on surface and remicon in order to reflect site condition.
-
This study is alkali-activated slag-red mud soil mixed pavement of efflorescence characteristics analysis of mitigation measures is drawn to the red mud substitution rate in accordance with the alkali-activated slag-red mud soil mixed pavement of efflorescence characteristics were exhibited. As a result of alkali-activated slag-red mud soil mixed pavement is more substitution rate increases appeared to efflorescence is increased.
-
The safety concern of slipping on floors in South Korea has come to the fore as a social problem, but the occurrence of such accidents has not decreased. Slip and fall accidents have several causes, but they are especially common when there is soapy water on the floor during a shower or a bath. Despite this situation, it can be said that there is a lack of standards on surface contamination materials used in floor slip resistance testing. Therefore, in this study, we conducted a survey to identify the components and quantity of soapy water that actually results from a user taking a shower, and the standardization of contamination materials. Based on the results of this experiment, we provide a surface contamination material that can replace the soapy water used in floor slip resistance testing.
-
Architectural fabrics are now used in membrane structure with the merits of free shape, lightness and opened up new possibility for the design of new building structures. Recently PVC, PVF, PVDF, PTFE coated fabric for using the membrane structures. However, clear standards for the design and construction is not exist because of the lack of Architectural fabric research. In this paper, Flammable properties of PVDF, PTFE coated fabrics are obtained through the Flammability test using the Cone Calorimeter. Based on these results, identify the fire resistance property of the Architectural fabric.
-
This research reviewed the characteristics of waste concrete sludge occurred from recycled aggregate producing process and the physical and mechanical properties of the mortar incorporated the pulverized the waste concrete sludge. From the results of the experiment, as the replacement ratio of waste concrete sludge powder was increased, the dosage of superplasticizer to satisfy the target flow of 200 ± 10 was increased, and the compressive and flexural strengths were decreased. On the other hand, when the sludge powder replacement ratio was 25 %, outstanding performance of general characteristics of mortar was obtained while it was lower than Plain mixture, thus, further detail study on various replacement ratios of waste concrete sludge powder is needed.
-
Thermal deformation behavior of high-strength concrete (HSC) exposed to fire is different from that of normal strength concrete (NSC). In case of ultra-high-strength concrete (UHSC), it is well known that thermal deformation behavior is greater than HSC. With increasing research of UHSC in buildings, it is necessary to understand the performance of UHSC at elevated temperatures considering loading condition. Therefore, evaluation on properties of thermal strain behavior properties of ultra high strength concrete by loading and high temperature was conducted.
-
Modular construction technique is an adaptation of factory-based mass production concept in ordinary manufacturing industries to construction industry and it assumes that panels, units, etc. are fabricated in factories and assembled in construction sites. Given its structural limitations, modular construction technique is primarily used in low-story buildings whose maximum height is usually five stories, but researchers are actively studying possible adaptation of modular construction technique to high-rise building designs these days as in the case of infill-type modular construction design. Infill-type modular construction technique, most frequently used in high-rise building construction projects, completes frame construction first in reinforced concrete structures and fills unit modules in such structures. However, infill-type modular construction technique leads to longer construction schedule accompanying increase in construction cost, cost overrun due to additional of temporary work, and possible damage to units in the wake of facility construction. Accordingly, this study is performed as a basic study for the development of bottom-up infill-type modular construction technique intended to construct structural frames and fill in units sequentially in a bid to address such drawbacks of current infill-type modular construction technique.
-
Because of energy crisis at all around the world, there is many method and system which for improving energy efficiency has appeared in construction industry. And then, 20% of entire building energy loss is emissed to exterior of buildings, that is important to building's entire energy efficiency. So, many research has been conducted for imporve exterior energy efficiency and generally it called insulation of wall. Method for wall insulation can be classified interior system and exterior system which defined installation place of insulation board whether interior or exterior of structural wall. However, interior system has thermal problem such as thermal-bridge which can be necessarily occur condensation. and exterior system has constructional problem such as difficult to construction because exterior and finish work so expensive construction cost than other insulation method. Thus, sandwich insulation wall system has been appeared for solving these problems. Sandwich insulation system must using wall connecting things because both side walls is divided by center insulation. At this, Through the heat at wall connecter, it can be occured thermal-bridge and broken insulation board when under construction will be bring negative effect by reducing wall thickness and insulation deficit. At this study, we were compared previous sandwich insulation system and analysis these system's problem for develop the improving constructability and performance of sandwich insulation system.
-
SMART Frame is a composite precast concrete structure system to deliver the advantages of both steel frame and reinforced concrete. Many studies have established to date that SMART Frame is more advantageous than conventional frame-type structure in terms of structural stability, constructability, economic viability as well as reduction of construction schedule. However, such studies have focused primarily on wall-type or flat slab-type apartment housing structures, failing to include Rahmen structures in their scope. Accordingly, this study aims to analyze the benefits of potential application of SMART Frame to RC Rahmen structures. As the structural stability and constructability of SMART Frame is already proven, this study reviews its benefits from the perspective of cost reduction. Conclusion of this study will be used subsequently in predicting the benefits of SMART Frame when it is adapted to RC Rahmen structures.
-
Resource procurement and material handling are considered as a significant part of construction project especially in large or tall building construction site. There are multiple variables that must be considered in a construction site during finishing work such as movement of materials, equipments, and workers. Therefore, it is difficult for construction workers to find the material handling path solely by intuition. The aim of this study is to propose a real-time path finding model suitable for complicated logistics flow in the field. The model explores the optimal transport path of finishing material with its basis on optimization algorithm, and it determines the direction of the Smart Sign. The proposed model is expected to be utilized for planning of efficient finishing material handling.
-
Construction project involves numerous repetitive operations. Especially in high-rise and apartment houses projects, the amount of repetitive operations increase and a preceding operations delay causes serious damage to the total duration of the project. This study deducts work delay factors by site engineer interview and survey. The study analyzes daily report data to deduct crucial processes affecting masonry work which has been investigated to be one of preliminary processes conducted at the beginning of finish work.
-
Starting from Guggenheim Bilbao Museum in 1997, it has been increased steadily that complex geometry buildings using digital designs and construction process. Since 2010, the domestic Freeform design has been widely used for buildings such as Dongdaemoon Design Plaza, Seoul City Hall, Tri-Bowl, and etc. But there are many defects such as the increased cost and period of construction, and the declined quality of construction because of the lack of optimized method and engineering experiences. Therefore, this study has an effort to review case study of the recent freeform buildings and construction methods using digital fabrications. And this study proposed the improve method for the construction quality for freeform buildings.
-
Various vibration caused by construction vehicles and equipment movement, rock blasting, and crushing obstacle occurs inevitably in construction sites. In this study, we measured the impact of vibration by blasting rock at construction sites, rock crushing, concrete crushing. The measuring instrument was installed in adjacent buildings and observed that blasting vibration differs depending on the charge weight, blasting distance, and the measuring position. The observation was maintained by allowable peak particle velocity standard according to each standards and references.
-
In this study, the experimental study on Insulation performance of insulated forms utilizing NT frame heat insulation at low Temperature. For this study, placing insulated TEGO film plywood based form between two constant temperature and humidity chamber that maintaining 10℃, decrease temperature of one chamber to -10℃ and -20℃. Each of steps, maintaining period of temperature was 1 hour. After placing the insulated form, measure temperature of outside if insulated form. As a result of experiment, temperature difference of Fumed Silica Vacuum insulation was lowest.
-
The production technologies of free-form concrete panels are emerging to satisfy the need of modern complex shaped in architectural design. This study aims for introducing and improvising the innovative technique called Rod type mold that overcomes the difficulties in some extent by enabling the mold to be used many times, making the shape of the mold adjustable in a flexible way and describing its production process to provide the alternative solution for the construction of free-form mold with considering the features including reusability and optimization cost across its production process. In this study, the freeform concrete panel shape was designed and experiment was done using computerized numeric control machine and rod type mold. The problems appeared on achieving desired shape while operating on rod type mold. The process of identifying all the root causes and contributing causes that may have generated an undesirable condition were done. Consequently, the conical or semicircular shaped was proposed for the end of Numerical control rod and replaced it with the existing flat shaped end to avoid the detachable problem and to improve rod type mold performance.
-
More than 50% of the existing buildings in Korea are over 15 years old. Therefore it is necessary to be held reconstruction or remodeling deteriorated buildings more efficiently. Especially, since remodeling project reserves existing structures, it requires less period of project and construction period compare to reconstruction. It is possible to minimize uncertainty in communication between participants and able to manage information and construct efficiently in remodeling projects. This paper is first step of integrated BIM-based whole lifecyle management of apartment remodeling process. It suggests 3D laser scanner specification factors and site constraint factors for mapping between two groups. Therefore it will contribute to develop mapping algorithm of two groups and find optimal combination for apartment remodeling.
-
The Standard penetration test determines the type of soil according to soil bearing capacity, and this classifies the subsoil into many layers. Construction project managers are willing to know the depth of the present types of subsoil on site in order to make plans on earthwork stage during excavation. However the standard penetration test may not provide accurate information on subsoil type due to incorrect spacing. To solve this problem, this study propose a conceptual algorithm for determining the spacing of standard penetration test spots to essentially tests relevant locations on which to be applied the standard penetration test. This provides the acquirement of the accurate layered model volume of earthwork revised into geological columnar section. This algorithm will determine the appropriate standard penetration test spots spacing on a given size of site to optimize the accuracy of the earthwork volume, time and cost.
-
The construction finishing work is emphasized according to high dependence on labor and long term that occupy approximately 40% in construction period, so that it is required for the alternatives such as automation technology. However, it is insufficient to develop the automation technology of construction finishing work compared to other works, for instance, frame work. Also it is not enough about this preliminary research which survey the improvement needs to select the development object. Therefore, this study aimed at derivation of detail works required improvement in ceiling finishing work by the questionnaire survey. These results may provide the basic information to develop the automation technology of construction finishing work.
-
Slim Floor construction method has to increase the available surface area thereby reducing the depth beams and slab. In addition, In this study compostie beam assembly of plates, square-shape steel pipe and deck plate. So workabiltiy is superior to the upper concrete possible without formwork. In the present study is strength test in progress in development slim floor composite beam used plate and perforated square shape steel pipe and obtained anlysis and conclustion of the experimental results.
-
Construction Cycle Trend Survey, which survey total value of orders and realized amounts monthly, is a valuable statistics that used to quick grasp or forecast the trend of domestic construction business. In recent periodical survey quality diagnoses, few professional users named a problem that Construction Cycle Trend Survey could not get together with the current state of the construction industry. This study examined weather Construction Cycle Trend Survey reflects the economic sentiment of construction business or not. Paired t test was performed between Construction Cycle Trend Survey and Construction Business Survey Index (CBSI), and significant differences were verified.
-
When starting a new project, generally similar existing projet are searched. As Building Modeling Information(BIM) has short history and experience, the dependence on similar project is high. Small and medium sized design companies are depending on website search tool for information of BIM project besides companies maintaining the Database(DB) from lots of project experience. However, the information level and contents provided by websites differ drastically from each other which makes it difficult to utilize the information and apply cases. Furthermore, the different classification system of the sites makes the situation even worse. Therefore, we collected and analyzed over 100 BIM cases from 18 global websites, to develop a system for BIM case application. Result showed that over 90% of our subject pool provided basic information including the construction type, characteristics of the client (public/ private), location of the project, and detailed information such as primary usage. Moreover, the reasons for applying BIM where to solve problems of geometric design, building system like MEP and construction. Furthermore, there was a contrast between cases conducted only within Korea and cases conducted with other countries. While there was almost always helpful information regarding the administrative steps for Korean BIM cases, there was close to no information for projects carried out outside of Korea. These results could contribute to verifying the trend of information provision of the websites for BIM projects data, and this is believed to be helpful for developing an application system for BIM cases which have an organized information provision system and level as well as for bench marking.
-
In tall building construction, time for transporting form affects formwork duration as plan size has become larger and quantity of inputted form has been increased. Thus, necessity of systematic dismantlement sequence of form has been increased to reduce the duration of formwork. Tabu search has been efficiently applied to solve problem of combinatorial optimization by using tabu list which can improve combination values. Therefore, this study proposes optimization model of dismantlement sequence of table form which has been preferred in tall building construction, to reduce the formwork duration by minimizing time for transporting form.
-
In Korea, it raised the need of the specification of unit modular construction, because there are no standard or manual. And it is urgent that the specification of unit modular construction is needed to develop in the domestic. Therefore, this study aims to propose the manual framework of the construction method. In the future, this framework will be based on the development of the manual on the unit modular construction method.
-
The unit modular method is one in which unit modules are prefabricated at a factory and then constructed at a construction site. That is why an important process, transporting unit module, is added in this method. The purpose of this study is to analyse the load for transporting unit module. The results of the analysis of the driving experimental runs revealed that a maximum load of 15 kN was applied on adapter block type A and a maximum load of 25 kN on adapter block type B. These loads were recorded at the points in the road test when the low-bed trailer was driving through unstable sections of the test such as stopping, restarting, passing over a speed bump or taking a left turn at speed.
-
In light of the recent media outlets revealing structural waterleakage problems, construction workers, design planners and related enterprises are investing more effort towards forming a solution plan for these issues. This study proposes the structuralization of a information network system that allows the selection and discussion of optimal measures for waterproofing related techniques and expert informations online in a realtime setting.
-
Demands for free-form buildings are on the rise, but such building designs require most cost and longer construction schedule, with less constructability due to challenges in construction member production and installation. FCP production technology has been developed using CNC machine in a bid to resolve the difficulties of member production. Exterior finishing panels of free-form building design must be divided in size and shape that can be produced by CNC machine. To solve this problem, constraints of CNC machine and correlations between CNC machine and panel need to be reviewed. Thus, the purpose of this study is to analyze decision factors on free-form concrete panel sizes produced by CNC machines. Through this study, FCP size can be optimized, which in turn can lead to improved FCP productivity and aesthetical quality of free-form building designs determined by the pattern of exterior finishing panels. CNC machine-enabled free-form concrete panel production technology will apply on site in the future, which will not only maximize the economic benefits of the technology but also support shorter construction schedule and better constructability.
-
Due to the nature of construction industry which is labor-intensive and outdoor mobile production industry, climatic changes work as a major factor affecting construction period and safety accident. In Korea, changes in the amount of precipitation are more severe than those in climate. In addition, climatic changes are also shown as a change in precipitation form. Thus, this study aims to provide baseline data for establishing safety regulations at construction sites by analyzing fatal accidents by precipitation type.
-
Recently, mechanical and electrical construction are getting more important because of technology advances. In particular, construction market has become more competitive and construction requires more complicated and sophisticated works. Despite its importance, relatively little studies on construction management for mechanical construction and electrical construction. Therefore, this study conducted an analysis to identify the relationship between construction planning and project performance. For the analysis a number of mechanical professionals were participated. Ultimately, the study will provide a foundation of effective construction management for mechanical construction.