By amending of the special law on the safety management of the facility, pumping station has been incorporated into kinds of facilities. In this paper, a case study for condition assessment of pumping station is conducted according to the detailed guidelines established for pumping stations. Evaluation index between new and existing guideline is compared.
It is to confirm the various causes for cracks in concrete lining and understand the reasons for major cracks by analyzing on-site constructional conditions. Also, it is to identify the bahavior of concrete lining for its main cause of cracks.
Reconstruction of the bridge is constructed to well foundation at the basement. Therefore, the existing bridge should evaluate the impact according to blasting construction. The result of displacement are presented the standard dispacement of the existing bridge.
Based Recently, Box type Precast segment Retaining wall with the Relieving Platform has been developed. In this study, it is going th measure that the effect of reducing the earth pressure by placing the Relieving Platform on field.
Simulation studies were performed to study the possibility of tensile force monitoring with piezoelectric sensors attached on anchorage devices of bonded tendon systems. The results showed that the impedance signals from piezoelectric sensors has sensitivity enough to evaluate the effective tensile force.
A new electromechanical impedance-based method was proposed to estimate the remaining tensile force of post-tensioning system. It was applied to a real-scaled anchorage system which has 19 strands, wedges, and anchor head, a bearing plate, and a steel duct. Experimental results showed that the proposed scheme has great potential to evaluate the remaining tensile force quite accurately.
A standard design section of a FRP DSCT wind power tower supporting 3MW was suggested and designed through AutoDSCT and CoWiTA programs. The thicknesses of the FRP tubes were optimized and by using the parameters of designed tower, the performance of the new type wind tower was evaluated via FAST program.
In this research, the experimental works were conducted to study the quality control for the compressive strength and pavement thickness of Hwangtoh concrete(21MPa) using the ultrasonic pulse velocity method and the impact echo method of nondestructive test methods based on the stress waves.
This study was to analysis the hydration heat and crack index considering the buttress part of the basic nuclear containment walls. The maximum hydration heat of buttress part was higher about 6% than those conventional containment wall. Also, early crack index of buttress part by hydration heat was decreased about 26% than conventional containment wall. Whereas the crack index by external restraint were similar on the all of specimens.
Recently, various types of landslide occurs frequently in domestic and foreign. The purpose of this study is to evaluate dam safety due to landslide in dam area. In order to evaluate dam safety on overtopping which may be occur by landslide, the scales of landslide were calculated through empirical formula and results of field survey in valleys, and wave heights of impulse were computed through numerical simulation for each case. Dam safety assessment was performed by the numerical analysis.
It is important to analysis a Response change of measured data in order to observe displacement of Dam. So, we are able to judge what problems happen in dam throughout this analysis. In this study, Response Change judged abnormal behavior show about an example of analysis on a Dam in South Korea and we supposed current condition of this dam.
In this study, Cavities in Specimens were find using GPR equipment. Results of exploration deadline for plain concrete, reinforced concrete, asphalt, gravel, depending on the type, asphalt pavement was most clearly exploration. Developed GPRiPP can represent a good cavitation through the image processing with the background removal.
This study evaluates the material performance of slump value and compressive strength of the concrete which was made by recycled sand and blast furnace slag powder(BFSP). The main variables are replacement ratio of BFSP. As a result, it was evaluated that more detailed evaluation is needed in long-term strength development and the compensation of slump value to the replacement ratio of BFSP.
For evaluating the hydraulic safety of a dam, an accurate evaluation of the hydraulic capacity of the spillway is most needed. Because almost existing small dams have been used the empirical discharge equation, it made some discharge trouble at the dam in flood. This study is showing a case study of evaluation method of morning glory type spillway that is required the best of care and is comparing new capacity with existing.
Defects of diversion tunnel have been analyzed by using the precise inspection for safety and diagnosis in 7 dams. Leakage from joint, crack, and material segregation is crucial damage in dam as well as crack, corrosion, and drainage system. Maintenances of diversion tunnel have been suggested with common and unique characteristics of defects.
Many of the reservoir is surrounded by mountains, and many reservoirs slope are not receiving proper maintenance. The slopes of adjacent to the reservoir is the blind spot of the administration. Landslides in the reservoir had caused the destruction of the structure from wave and overtopping. In addition, this has a severe impact on the stability of the downstream portion. In this study, an infinite slope stability analysis utilizing the on-site investigation and SINMAP be performed for vulnerability analysis of the landslide of adjacent to the reservoir.
The purpose of this paper is to find an limitation to detect the defect of damaged asphalt pavement structures for improved infrared thermography. We use heat source of a natural light to detect the defect efficiently. The heat source was applied to the asphalt specimens containing maximum depth of 3cm internal timber. It was found that the depth of 3cm internal timber could be detected by this method. In addition, we used the improved image processing to make the damage zone displayed clear in the image obtained from the thermographic operation.
Structural performance of cable-bridge has been evaluated based on the field load test and the measurement monitoring system of existing Nielsen arch bridge. The measured acceleration data was converted to the displacement of girder and the tension of cable in the process of numerical integration and maximum frequency detection algorithm..
Impact factor for used in the load carrying capacity evaluation of bridges is varied depending on vehicle speed and bridge frequencies. So, it is hard to define its peak value since in the field test the truck speeds applied cannot cover all possible vehicle speeds and the speed per each vehicle loading test cannot remain constant consistently. Furthermore, the target bridges should be closed during field test, which leads to an inconvenient traffic flow. In this paper, a displacement-based response spectrum of bridges is considered to define the peak impact factor without conducting the standard vehicle loading test, while using a bridge operational traffic condition.