ABSTRACT:
Under China’s great plan to develop the western part of the country, infrastructure development is booming in the region and numerous construction projects have sprung up everywhere. Geotechnical work thus requires special attention in the region. This paper presents an overall account of the recent development in Western China and the challenges and opportunities existing in the country. The paper also reviews the geotechnical conditions in the mountainous region, the planned and on-going engineering projects on various scales, and the geotechnical challenges facing these projects. Particular references are given to the southwest provinces of China, which are the tributaries to the Yangtze River. Typical past geohazard events will be presented and concerns related to engineering projects will be discussed.
1 OVERVIEW OF TOPOGRAPHY AND GEOLOGY IN WESTERN CHINA
1.1 China''s topography
China has a vast land. Its topography varies widely, overall sloping from west to east. It can generally be divided into three giant steps as shown in Figure 1. The Qing-Zhang highland plateau with an average elevation of 4500 ¨C 5000 m, covering southwest China, most of Qinghai, Tibet and part of Sichuan Provinces, the low land along the east coast with an average elevation less than 100m and the intermediate step covering the rest of the county. The Qing-Zhang highland plateau is the highest of the steps. This region is in sharp contrast with its surrounding areas. In the north, its elevation drops by nearly 4000 m in a short distance. In the southwest, within a few hundred meters of horizontal distance, the elevation rises rapidly from less than 100 m in India to over 6000 m in the Himalaya Mountain ridge, with the Everest Peak at 8848 m. In the east, the elevation drops by approximately 3000 m to 300-400 m in the Sichuan Basin.
