• Journal of Korean Society of Steel Construction
• /
• v.18 no.3
• /
• pp.395-403
• /
• 2006

Recently constructed bridges often have long spans and simple structure details considering not only the function but other important factors such as aesthetics, maintenance, construction duration and life cycle cost. Therefore, bridges require high-performance steels like extra-thick plate steels and thermo-mechanical control process (TMCP) steels. TMCP stels are now gaining wide attention due to their weldability improved strength and toughness. Recently, SM570-TMC steel, which is a high-strength TMCP steel with a tensile strength of 600 MPa, has been developed and applied to steel structures. However, using this steel in building steel structures requires the elucidation of not only material characteristics but also the mechanical characteristic of welded joints. In this study, high-temperature tensile properties of SM570-TMC steel were investigated through the elevated temperature welded joints of SM570-TMC steel were studied through the three-dimensional thermal elasticplastic analyses on the basis of mechanical properties at high temperatures obtained from the experiment.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.14 no.4
• /
• pp.397-419
• /
• 2012

The pressurizing support tunneling method has been developed that overcomes shortcomings of conventional trenchless methods and applied to the field. The main concept of the new method is the pressurization system which, by means of pressurization bag between outer flange of steel ribs and excavated perimeter, applies higher pressure than the pressure relaxed by excavation to the ground to prevent ground displacement. The stability of the support members and effect of displacement control of the new method were verified through 3D numerical analyses. The new method was applied to the construction of a 10.7 m wide, 7.9 m high and 85 m long ramp tunnel that passes under ${\bigcirc}{\bigcirc}$ Expressway. By applying the new method, the tunnel construction was successfully completed in 13.5 months which decreases construction time to 35% compared to conventional methods, and ground displacement was almost negligible.

• Journal of Korean Society for Geospatial Information Science
• /
• v.4 no.2 s.8
• /
• pp.195-203
• /
• 1996

The 3-D analysis of terrain for route design and selection is being used as important basic data for effective judgement of political draft. This study is to decide efficient alignment of the entry route and design bridge by modeling, analyzing and displaying surface with digital terrain data. In this study we analyze slope, aspect, shaded-relief, line of sight and watershed on the base of DTM such as contour, TIN and grid. And we can not only esti mate end-area volume for road construction by calculating cut and fill and displaying mass-curve but also recognize the scene after execution with simulation of road and terrain. The result of this study reveals that visual effects of the 3-D terrain data are very effective for designer and decisionmaker to select and review alternative route with regard to terrain characteristics.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.22 no.2
• /
• pp.95-103
• /
• 2004

Recently, many troubles about the right of light have been arising ceaselessly as taller and more dense the buildings have been in the urban. The present time, the right of light is not stipulated legally. For solving above problems, there spend so too much lawsuit expenses and time on the damages about construction stopped and delayed, according to subjective decisions instead of scientific and rational solutions. The past studies of the right of light weren't based on the analytic data and depend on the simple view of point. So, those of studies gave trust to people hardly, only were treated as the ways on the decision about construction among non-engineers. Therefore, this paper studies the efficient solution of problems about the right of light through analysis about mass of sunlight according to season and the hour using a simulation technique on the civil construction.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.60 no.4
• /
• pp.15-25
• /
• 2018

The accident risk at the construction workplace associated with agricultural engineering is comparatively higher than those of other fields due mainly to its complex work types and processes. Agricultural engineering deals with a variety of agricultural infrastructures from irrigation and drainage facilities to giant-scale coastal reclamation land infrastructures. The characteristics that most agricultural projects have conducted on a small-scale even worsen the situation drawing low attentions to risk management. Therefore, systematical risk assessment that focuses on details of agricultural construction work process is required in order to enhance safety management capacity and to prevent repetitive accidents ultimately. This study aims to categorize construction work types and processes of agricultural construction works, and to quantitatively assess the accident risk of them based on accident analysis. Regarding classification of construction works, actual 827 accident cases were thoroughly reviewed and coded by their construction site, facility and work type, project scale and so on. Most accidents (71.8 % of total cases) occurred in small-scale construction workplaces with less than 5 billion Korean won project budget. And those accidents related to agricultural infrastructure project (37.4%) and agricultural water development project (22.4%). In terms of work types, accidents frequently took place in form-work followed by pipe installation work, steel bar work and concrete work. The potential risks were compared with actual outbreak of accidents based on Analytic Hierarchy Process (AHP). The results show that the potential conditions of accident expected to be took place is somewhat different from the actual conditions where accidents actually happened. This implicates that risk management manuals or education needs to be adjusted by reflecting unexpected circumstances. Overall, this study is meaningful in that the results could be foundations as to strengthen risk management capacity for agricultural engineering projects.

• Korean Journal of Construction Engineering and Management
• /
• v.8 no.6
• /
• pp.207-215
• /
• 2007

The purpose of this study is to predict the long-term maintenance expense of BTL school projects which were ordered from the Ministry of Education and Human Resources Development and each Metropolitan and Province Office of Education. For conducting this study, the adapted research method includes a case study of BTL school projects ordered from Seoul Metropolitan Office of Education in 2006. After examination of initial investment based on each $school^{\circ}{\phi}s$ operation account, it estimates maintenance expense and long-term maintenance expense. Also it compare using two methods: one is the long-term maintenance expense estimation in apartment houses and the other is AEAM(annual equivalent amount method). The results of this study are as follows: 1) It is analyzed long-term maintenance expense rates of each BTL school. As a result, it is construction(14.0), civil(1.4%), mechanical(6.5%), equipment(6.5%), electronic(11.0%), fixture(5.1%) and the rest(1.0%). 2)It is applied using two methods: one is the long-term maintenance expense estimation in apartment houses and the other is AEAM. Finally, It is compared expense deflection per $100{\beta}{\ge}$ in each month.

• 기술발표회
• /
• s.2006
• /
• pp.146-155
• /
• 2006

A study for damage degree and reduction programs of disaster was performed after collecting and analyzing the damage data by the type of flood damage resulting from the localized rainfall Gangwon area has been damaged by heavy localized rainfall between July 15 and 17 in 2006 Specially, a number of people was killed and much properties were lost in Inje, Yangyang and Pyeongchang area Recently, the damages by debris flow has been increased more than any other disaster causes, because heavy rainfall closed to about 100mm/hr by global warming in short time has been developed frequently. In other words, an area forming a highland has a potential debris flow Therefore, in this study, the damages data by debris flow in the area of Inje and Yangyang were collected and analyzed to consider the type of flood damage In future, it must be tried to find a complementary solution and establishing management system for debris flow when the civil construction begins

• Land and Housing Review
• /
• v.2 no.1
• /
• pp.47-52
• /
• 2011

Recent advances of technology in materials science have made it easy to respond to user's needs on high performance steel in civil and building structures. The high-performance and high-strength steel are required for large scale structure and high-rise building to have high-strength, high fracture toughness and better weldability etc. Therefore development of 600MPa class steel for mega structure is necessary. high strength steels, however, may have mechanical properties that are significantly different from those of the conventional steels. The application of high-strength steels to building structures should be reviewed as to whether inelastic behavior equivalent to that of conventional steels can be attained or not. This study researched the structural behavior of high strength circular tubes compression and under flexure. Three column tests and three flexural tests were carried out. The suitability of existing design formulae(KBC 2009) and the structural behavior were investigated through these columns and beams with various types.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.4 no.1
• /
• pp.27-35
• /
• 2002

For the excavation of the rock, blast method is put into operation in most of the construction site in Korea. In comparison to other methods of excavation, blast method has many merits such as improvement in efficiency in operation, reducement of operation period, and etc. However, blast operation also creates much loss due to the blast vibration, noise, and fly rocks. Thus, in this study, we have examined main features, rock fragmentation effect and the application of plasma method the one of shallow vibration method. In this study, the attenuation exponent of blast method operated in the site was 1.39~1.40 and that of the plasma method was analysed to be 1.45~2.23. From the location where the distance between excavation location and observation location was over 15 m, most of excavation vibration were measured to be less than 0.2 kine(cm/sec), which is also the allowed standard value of sensitive buildings, such as cultural assets and computer facilities. According to the result of FFT(Fast Fourier Transform) analysis, the frequency measured through blast method in this site was 30~50 Hz and the frequency of plasma method ranges in between 30~130 Hz.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.36 no.4
• /
• pp.235-243
• /
• 2018

The national geodetic control point is very important as a framework for drafting plans for construction and civil engineering works as well as mapping for various development and utilization plans related to the national land. Since the 1910s, Korea has established and managed the national geodetic control points, the triangulation points and the benchmarks. Currently, these point information is provided through the land information platform. The national geodetic control point has been changed through the process of loss, re-establishment, and re-location by the events and environment of the times. Therefore, it is very important to provide information by linking these past national geodetic control points in time series. In this study, we classified the triangulation points into five groups(Japanese Government General of Korea, YUCCA Project, National Construction Institute, Past Control Point Data Sheet, and Current) by age and then suggests a method to match the same control points in each time period. Finally we also applied the proposed method to Jecheon and analyzed the results.