introduction to earthquake resistant design of buildings 建筑抗震 .ppt

Introduction to Earthquake Resistant Design of Buildings 建筑抗震設計簡介 presented by Ir Dr Y. L. Wong 黄玉龍博士 Associate Professor Dept. of Civil Structural Engineering Content (內容) Earthquakes（地震） What causes earthquakes and how do they happen? Earthquake Resistant Buildings （抗震設計） How could engineers design buildings that survive in earthquakes? Acknowledgements (致謝) Most of the materials in this presentation were extracted from websites of “Introducing and Demonstrating Earthquake Engineering Research in Schools” (IDEERS) of Taiwan National Center for Research on Earthquake Engineering (NCREE) and University of Bristol. PGA Zonation Map of South China南中國地震設計加速圖 Earthquake (地震) Earth‘s Structure(地球的構造) Tectonic Plates (構造板塊) The surface of the earth is made up of 21 tectonic plates, some large and some small, that are constantly moving. As the plates are forced against each other, they deform, and eventually they crush and fracture. The sudden fracture of the rock sends out a shock wave that causes the earths surface to shake. This is one way earthquakes can happen. Fault (斷層) Over millions of years the earths tectonic plates have been moving continuously and pushing against each other. These movements have forced them to deform producing mountains and valleys in the earths surface. Sometimes the rocky surface of the earth has just been bent and folded (Fig.1). Sometimes the movements have caused the rock to deform so much that they fracture. These fractures are called faults (Fig. 2). When the rock fractures, its sudden movement causes an earthquake as shock waves spread away from it. Faults in earthquake (斷層實例) This fence crossed the San Andreas Fault. In 1906, the fault ruptured causing the Magnitude 8.3 San Francisco Earthquake. The horizontal movement of the ground caused the fence to move by about 2 metres Causes (地震的成因) Earthquakes can be caused by natural events or human activities. Here are some of the different causes of eart