• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.5
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• pp.751-760
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• 2018

Currently, the quality measurement of the work is carried out by the supervisor's visual inspection, as the workers individually judge the number of resolutions, thickness, speed and vibration. After work, we are conducting follow-up work through traditional spot test, which is less representative. Therefore, it is impossible to check the results of the resolution, and there is always the possibility that problems will arise due to poor construction. This study demonstrates the feasibility of using the continuous compaction strength measurement method by comparing the continuous compaction strength measurement method and the conventional compaction strength measurement method after performing the compaction in the actual field scale in various test conditions. The validity is verified by analyzing the Compaction Meter Value of an Intelligent Compaction roller composed of a Global Positioning System and an accelerometer, Based on the proven results, a full range of quality can be confirmed without a single test. The quality confirmation is visualized in the compaction control program developed in this study, This enables the field manager to perform real-time quality monitoring at the same time as compaction.

• Journal of the Korean Geotechnical Society
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• v.20 no.9
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• pp.133-144
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• 2004

Pre-reinforcement ahead of a tunnel face using long steel or FRP (Fiberglass Reinforced Plastic) pipes in NATM(New Austrian Tunnelling Method), known as the RPUM(Reinforced Protective Umbrella Method) or UAM (Umbrella Arch Method), is the promising method to sustain the stability of a shallow tunnel face and reduce the ground settlements. In addition, horizontal reinforcing of the face is recently emphasized to improve the stability of the face. However, the characteristics on longitudinal arching around the face have not yet been established quantitatively with the RPUM (crown-reinforcing) and/or the face horizontal reinforcing. In this study, therefore, the behavior of cohesionless soil around the face reinforced by the reinforcing member representing the RPUM and horizontal reinforcing is investigated through two-dimensional laboratory model tests. A series of tests were carried out on various conditions by changing lengths and angles of the reinforcing members. Based on the vertical pressure around the face, the characteristics of longitudinal arching have been found for the case of the non-reinforced and the reinforced.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.971-976
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• 2007

In the U.S., utility damages or utility delay caused by conflicts during the underground utility relocation is one of the weighty problem in the construction industry. Also, in domestic case, delay and additional cost caused by underground utility(i.e, electricity, communication, gas, water supply and sewerage) relocation has been happened so that there is an increase of claims for responsibility between owners and contractors. However, there is insufficient survey for the recent circumstance of additional cost for delay and design changes caused by utility relocation and shortage of enough research for solving and analyzing of causes and their ripple effect. This research presents a result of the study about the best practices of FHWA(Federal Highway Administration), SHAs(State Highway Agencies) and the utility companies managing utility relocation. Also, it presents the basic concept of SUE(Subsurface Utility Engineering), the most reliable tool of FHWA presented, and investigates the developing status about SUE in Korea. At the end of this paper, this research proposes a practical and more applicable study about the efficient utility relocation focusing on local industry.

• Korean Journal of Heritage: History & Science
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• v.48 no.4
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• pp.110-125
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• 2015

This study is objected to investigate the repairing method and the modification period of rafters via the transformation traces left in the superciliums, where repair process takes places frequently. This is the basic research of analyzing the architectural features of Deokkeori, one of the additional-rafter methods. Deokkeori method can be described as using Deokdori in the top section of Hayeon, and placement of Sangyeon above it. This method was started to be used since middle of the Joseon dynasty period(middle 18th Century) and mainly used at 19th Century to resist the transformation caused by repairing. It had been gradually developed from non-application stage to application stage including additional usage of complement. The architectural features of Deokkeori can be categorized into four. First, the usage of Deokdori to connect Sangyeon to the top section of Hayeon. It reduct the direct connection between Sangyoen and Hayeon, therefore give constructive benefits and prevent the downfall of the eaves by increasing the power which pressing the top section of Hayeon. Second, it gives the autonomy to the inside structure of ceiling by comprising it. By using Deokdori, the limit of top section's longitude was eliminated while also simplify the upper section by blocking the inside structures with ceiling. In addition, the complements occasionally seen in several buildings increase the power which pressing Hayeon. Third, the ceiling's slope has been changed to be concerned with Sangyeon, instead of Hayeon which was highly related with it before. The last factor is the thickness of rafters which used in Deokkeori. The diameter is thiner in Sangyeon than Hayeon.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.440-447
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• 2020

The demand for large-scale horticultural complexes utilizing reclaimed lands is increasing, and one of the pending issues for the construction of large-scale facilities is to establish foundation design criteria. In this paper, we tried to review previous studies on the method of reinforcing the foundation of soft ground. Target construction methods are spiral piles, wood piles, crushed stone piles and PF (point foundation) method. In order to evaluate the performance according to the basic construction method, pull-out resistance, bearing capacity, and settlement amount were measured. At the same diameter, pull-out resistance increased with increasing penetration depth. Simplified comparison is difficult due to the difference in reinforcement method, diameter, and penetration depth, but it showed high bearing capacity in the order of crushed stone pile, PF method, and wood pile foundation. In the case of wood piles, the increase in uplift resistance was different depending on the slenderness ratio. Wood, crushed stone pile and PF construction methods, which are foundation reinforcement works with a bearing capacity of 105 kN/㎡ to 826 kN/㎡, are considered sufficient methods to be applied to the greenhouse foundation. There was a limitation in grasping the consistent trend of each foundation reinforcement method through existing studies. If these data are supplemented through additional empirical tests, it is judged that a basic design guideline that can satisfy the structure and economic efficiency of the greenhouse can be presented.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.6
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• pp.177-187
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• 2016

This study started with the question, "Is the cost of landscape construction work in residential areas measured by public enterprises, 'in response to the needs of consumers?" The study analyzed whether the landscape construction expenditure is being introduced at an appropriate ratio according to the value the residents have regarding landscape elements. Following this, research was conducted for the purpose of providing basic data for improving the efficiency of formulating apartment landscape construction costs in the future. This research proceeded based on a questionnaire survey of residents of apartments, and the content of the questionnaire used frequency analysis and descriptive statistics research methods. To take a look at a comparative analysis of value recognition, in particular, a comparative analysis was performed based on the actual input cost based on the ratio of landscape elements by layer. Conclusions were found as follows: First, the degree of interest in the apartment landscape of the tenants was high, and the value of the landscape was high but realistic satisfaction appeared comparatively low. Second, the awareness of residents' values regarding landscape elements appeared to give "plantings" more value than "facilities". Thirdly, as a result of a mutual comparison between the values recognized by the resident regarding landscape elements and the construction input fee, depending on the landscape elements, it appeared that there is a difference in the ratio of up to 52 times from 1.25. Fourth, the fact that there is a difference in the relative proportion of value recognition and inputting construction cost indicates that it is not possible to respond to the needs of tenants during the construction cost development process. It also shows that the utility of inputting construction costs is low. Therefore, a macro-level examination such as reflecting the existing inflation rate is necessary to develop the efficient landscape construction cost of apartment such as the awareness of the value of the residents regarding landscape elements, out of the customary construction cost formulation method based on the microscopic dimensions of the consumer side.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.2
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• pp.103-119
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• 2023

Since the Korean government has decided to apply the policy of BIM (Building Information Modeling) to the entire construction industry, it has experienced a positive trend in adoption and utilization. BIM can reduce workloads by building model objects into libraries that conform to standards and enable consistent quality, data integrity, and compatibility. In the domestic architecture, civil engineering, and the overseas landscape architecture sectors, many BIM library standardization studies have been conducted, and guidelines have been established based on them. Currently, basic research and attempts to introduce BIM are being made in Korean landscape architecture field, but the diffusion has been delayed due to difficulties in application. This can be addressed by enhancing the efficiency of BIM work using standardized libraries. Therefore, this study aims to provide a starting point for discussions and present a classification system for objects and attribute information that can be referred to when creating landscape libraries in practice. The standardization of landscape BIM library was explored from two directions: object classification and attribute information items. First, the Korean construction information classification system, product inventory classification system, landscape design and construction standards, and BIM object classification of the NLA (Norwegian Association of Landscape Architects) were referred to classify landscape objects. As a result, the objects were divided into 12 subcategories, including 'trees', 'shrubs', 'ground cover and others', 'outdoor installation', 'outdoor lighting facility', 'stairs and ramp', 'outdoor wall', 'outdoor structure', 'pavement', 'curb', 'irrigation', and 'drainage' under five major categories: 'landscape plant', 'landscape facility', 'landscape structure', 'landscape pavement', and 'irrigation and drainage'. Next, the attribute information for the objects was extracted and structured. To do this, the common attribute information items of the KBIMS (Korean BIM Standard) were included, and the object attribute information items that vary according to the type of objects were included by referring to the PDT (Product Data Template) of the LI (UK Landscape Institute). As a result, the common attributes included information on 'identification', 'distribution', 'classification', and 'manufacture and supply' information, while the object attributes included information on 'naming', 'specifications', 'installation or construction', 'performance', 'sustainability', and 'operations and maintenance'. The significance of this study lies in establishing the foundation for the introduction of landscape BIM through the standardization of library objects, which will enhance the efficiency of modeling tasks and improve the data consistency of BIM models across various disciplines in the construction industry.

• Journal of the Korean Geosynthetics Society
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• v.12 no.4
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• pp.67-76
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• 2013

Landfill require special care due to the dangers of nearby surface water and underground water pollution caused by leakage of leachate. The leachate does not leak due to the installation of the geomembrane but sharp wastes or landfill equipment can damage the geomembrane and therefore a means of protecting the geomembrane is required. In Korea, in accordance with the waste control act being modified in 1999, protecting the geosynthetics liner on top of the slope of landfill and installing a drainage layer to fluently drain leachate became mandatory, and technologies are being researched to both protect the geomembrane and quickly drain leachate simultaneously. Therefore, this research has its purpose in studying the drainage functions of leachate and protection functions of the geomembrane in order to examine the application possibilities of Geo-Multicell-Composite (GMC) as a Leachate Collection Removal and Protection System (LCRPs) at the slope on top of the geomembrane of landfill by observing methods of inserting filler with high-quality water permeability at the drainage net. GMC's horizontal permeability coefficient is $8.0{\times}10^{-4}m^2/s$ to legal standards satisfeid. Also crash gravel used as filler respected by vertical permeability is 5.0 cm/s, embroidering puncture strength 140.2 kgf. A result of storm drain using artificial rain in GMC model facility, maxinum flow rate of 1,120 L/hr even spray without surface runoff was about 92~97% penetration. Further study, instead of crash gravel used as a filler, such as using recycled aggregate utilization increases and the resulting construction cost is expected to savings.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.3
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• pp.267-274
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• 2017

This study discusses the applicability of environmental friendly EVA based butyl rubber self-adhesive waterproof sheet designed to prevent corrosion of large scale pipes used in the water treatment facilities during th water treatment process. The experiments conducted tested the waterproofing sheet's adhesion strength on the steel surface of the pipes and checked for whether the material has the proper response properties against the various environmental conditions. In addition, it the sheet adhered to the steel pipe was to see if the adhesion hold against the water pressure due to the ingress of inflow water. Finally, the waterproofing sheet's adhesion strength was tested on a rusted steel surface to confirm whether the material has the necessary properties to secure stable adhesion strength and prevent corrosion of steel pipes at the same time during the process of installation or maintenance. As a result, the self-adhesive waterproof sheets showed that all attachments in the untreated, long term pressuring, immersion in chemical substance (hydrochloric acid, hypochlorous acid, sodium hydroxide), low temperature ($-20^{\circ}C$) conditions showed a adhesion performance of higher than 1.5N/mm, which is the performance standard of KS F 4934. Also, in the testing to check for the adhesion property against inverse water pressure, it was observed that the adhesion failure did not occur even up to $3.0N/mm^2$ pressure. Also, in the process of assessing the adhesion performance on rusted steel surface, specimens after 12 hours of corrosion treatment was shown to have 2.1N/mm, and specimens after 168 hours of corrosion treatment was shown to have 2.0N/mm adhesion strength performance.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.2
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• pp.34-44
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• 2020

The purpose of this study was to investigate the difference in perceptions between gardens and park functions as recognized by two groups, Group A and Group B, in order to confirm the distinction between concepts and functions and then establish the importance of individual functions. The AHP was used to analyze the importance of each group's perceptions by dividing them into garden and park, Group A and non-Group A, respectively. In Group A, the importance of garden functions were considered in descending order of importance to be cultural function, ecological function, and social function. In the general group, ecological function, cultural function, and social function also appeared, but in a different order of importance. As for the park functions, Group A recognized the importance of functions in a similar order of importance to the gardens: cultural function, ecological function, and social function. Group B thought that social function, ecological function, and cultural function have the same significance. At the major classification level, Group A and Group B emphasized the social function of the parks. Group A recognized the importance of the garden's cultural function as the most important, whereas the general group emphasized the importance of the garden's ecological function. As for the mid-class level, Group A recognized the aesthetic beauty, health, ecological environment protection, and water circulation as important functions of the garden. For Group B, the ecological environment protection, aesthetic beauty, water cycle, and health were important. The concepts and functions of gardens and parks are still largely mixed but are gradually becoming differentiated. As a follow-up study, it is important to systematically manage the functions of gardens by establishing design, construction, and monitoring DB techniques for the garden type and examine the hierarchy of various other gardens.