| The 921 Chi-Chi Earthquake is the largest one in Taiwanese history over the past century. It generates thousands of casualties and causes severe economics impact and devastating construction damages. Taiwan has a high population density and limited land base. Ground land is particularly limited and hill area occupies more than 70% of its geographic layout. Many engineering and construction development of the hill usages in Taiwan are thus advanced due to the natural resource constraint. Unfortunately, the 921 Chi-Chi Earthquake caused severe damage to the slope area in mid-Taiwan. The mountain and hill collapse reaches 3% of the entire Taiwanese area. Therefore, the stability and sliding analysis of slopes becomes an important subject for construction research topics. The changes of the dynamic behavior of slope are affected by the wave characteristics, the geometric properties of the slope, material property and whether there exists a complex stratum and topography. In the past study, the most commonly used methods include static simulation, Newmark mass analysis, and dynamic numerical analysis. They all have their advantages and weaknesses. As a result of technological advancement, the dynamic numerical analysis method can provide the best simulation. This dissertation is based on the author's involvement with Chi-Nan University's high slope. It studies the pre-quake design, dynamic simulation, static and dynamic analysis, slope dynamic analysis and the checks optimization. Below is the summary of findings: (1) Evaluate the current slope dynamic theories in detail. They indicate that dynamic numerical analysis is the best simulation method yet still allows enough research space to reach a more optimal conclusion. (2) Analyze the sloping case study in detail, including the characteristics of the 921 Chi-Chi Earthquake, slope geological characteristic, pre-quake design, post-quake investigation, post-quake static and dynamic analysis, compilation of test results and analysis of the whole static and dynamics analysis.(3) Derive the optimal proposal for the slope to reach a cost saving of NT120,000,000 and reduce the construction period by half of the original proposal. Also, the safety of the slope will improve and the withstand able acceleration will increase from 0.33g to 0.58g.(4) To derive the optimal case for the slope construction, it is necessary to investigate the results from the four restoration proposals. In addition, the comparative analysis of the dynamic analysis must be evaluated and discussed in depth to determine the final proposal. (5) The careful consideration prior to the research analysis, such as earthquake, geology, experiment design, previous records of failures are important. The data need to fit four criteria: abundance, accuracy, compilation, and selectivity to reach meaningful conclusion.(6) Although the safety factor needs to be a minimum of 1.5 from the slope static force analysis, it does not necessarily guarantee the safety standard. There is also a need to perform slope dynamic analysis and then compare the static and dynamic analysis results to reach a reasonable, appropriate answer. It supports the view of Seed's proposal in 1979. (7) The corollary and all the peripheral conditions of the slope analysis need careful and comprehensive considerations. For example, the weak surface of the slope is critical and should not be ignored. If it is not understood and used properly, the results will be significantly off.(8) In the process of slope static force or dynamic analysis, all the geological and other related constants need to be selected thoroughly and professionally.(9) In compiling the restoration proposal, special attention needs to be given to the material, durability, form and characteristic of the construction body. Also the body should be carefully positioned to provide maximum safety and utility effect.
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