AN INTERDISCIPLINARY RESEARCH ON THE EFFECTS OF SURFACE GEOLOGY ON SEISMIC MOTION

近年来对减轻历次地震所造成的各种损害的方法研究，从抗震工程的角度提出了迫切需要研究的问题；即地表地质对地震地震动特征影响的定性和定量评价。本文通过评价地下岩土力学模型在地震地震动预测中的应用，讨论了地表地质的影响。通过对选定试验场的地下结构的岩土工程勘察和地震观测，获得了预报所需的资料。本文采用的地震动预测方法是盲预测试验，即根据给定的输入地震动和岩土地基模型估计盲点的地震地面反应。神奈川县的石原平原被选为我们的试验田。该项目的参与者包括地震学、土木工程、结构工程等理工科领域的研究人员。在三年的研究期间，每年年底举办两次全国专题讨论会和一次国际专题讨论会。这些专题讨论会的目的是在该项目的参与者与该领域的其他研究人员和工程师之间进行合作审查和交换意见。研究内容主要围绕以下六个方面展开：(1)某试验场地下结构岩土工程勘察与地质工程资料检验；(2)地下结构评价；地震地震动特征与微震测量的地震地震动特征(3)石原平原国际试验场地震动观测及观测记录评价(4)考虑地表地质的地震动预测方法评价(5)采用盲预测试验预测地震动计算方法评价(6)盲预测试验的检验与安排关于上述六个主题的争议点在本研究报告中进行了讨论和总结。少

Recent researches into methodology of reduction of various damages caused by past earthquakes have presented problems that should be examined urgently from the view-point of aseismic engineering; that is, those of qualitative and quantitative evaluations concerning effects of surface geology on characteristics of seismic ground motion. In this study, effects of surface geology are discussed by evaluating the geotechnical underground model used in a prediction of earthquake ground motion. The necessary data for the prediction have been obtained by the geotechnical surveys of underground structure and earthquake observation of the area chosen as a test field. The method of prediction of ground motion adopted here was the blind prediction test by which an earthquake ground response at blind sites are estimated on the base of given input ground motion and geotechnical ground model. Ashigara Plain in Kanagawa Prefecture, was chosen as our test field. The participants of this project were pi … More cked out among researchers of seismology, civil engineering, structure engineering and so on in the fields of science and engineering as well. During the three- year research period, two national and one international symposia were carried out at the end of each year. The aims of these symposia were to make a co-operative examination and to exchange opinions between the participants of this project and other researchers and engineers of this field.The contents of this research were concerned mainly with the following six themes:(1) Geotechnical Survey of Underground Structure of a Test Field and Examination of Data of Geological Engineering(2) Evaluation of Underground Structure, Seismic Ground Motion Characteristics and Seismic Motion Characteristics by Microtremors Measurement(3) Observation of Earthquake Ground Motion of Ashigara Plain International Test Field and Evaluation of the Observation Records(4) Evaluation of Prediction Methods of Earthquake Ground Motion Considering a Surface Geology(5) Evaluation of Computation Methods of Prediction of Earthquake Ground Motion by Adopting the Blind Prediction Test(6) Examination and Arrangement of the Blind Prediction Test Conducted at Turkey FlatThe controversial points concerning the six above-mentioned subjects were discussed and summed up in the report of this research. Less