矩形闭合地下连续墙桥梁基础竖向承载特性试验研究  

Study on bearing performance of rectangular closed diaphragm walls as bridge foundation under vertical loading

作　　者：文华[1] 程谦恭[1] 陈晓东[2] 孟凡超[2] 

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]中交公路规划设计院,北京100010

出　　处：《岩土工程学报》2007年第12期1823-1830,共8页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金资助项目(40172093);国家杰出青年基金项目(40025103);交通部西部交通建设科技项目(200331849457)

摘　　要：针对矩形闭合地下连续墙——一种新型的桥梁基础,进行了闭合墙基础的竖向载荷模型试验,对其荷载传递机理和墙体内、外侧摩阻力以及承台土反力的分布规律与发挥发展过程等作了系统的研究。研究表明:闭合墙基础的竖向承载力由外侧摩阻力、内侧摩阻力、端阻力以及承台土反力四部分组成。外侧摩阻力自上而下发挥,内摩阻力缓于外摩阻力自下而上逐渐发挥,由于承台的"削弱效应",上部墙段的内摩阻力接近于0。承台土反力分布的总体特征是承台角点处最大,边缘处次之,中心区最小。随着荷载的增加,闭合墙侧摩阻力增加趋势变缓,荷载分担比逐步减小,而墙端阻力和承台土反力的增加幅度逐渐变大,墙顶增加的荷载大部分都由墙端阻力和承台土反力分担。Model tests on rectangular closed diaphragm walls a new type of bridge foundation, were conducted. In the tests, the load transfer mechanism, distribution and development of inner shaft resistance, outer shaft resistance, soil resistance under the cap were studied. It was observed that the vertical load bearing capacity of closed diaphragm walls was composed by the inner shaft resistance, outer shaft resistance, toe resistance and soil resistance under the cap. The outer shaft resistance was developed from the top of the wall to the toe. On the contrary, the inner shaft resistance was developed from the toe to the top. For the ＂weakening effect＂ of the cap, the top inner shaft resistance was close to O. Distribution character istics of the soil resistance under the cap were that the soil resistance in the corner was the largest, secondly in the border and thirdly in the center. With the increase of load, the shaft resistance increased slowly and its load-shearing percent decreased gradually. At the same time, the increments of toe resistance and soil resistance under the cap were enlarged gradually, and the most of load increment was partaken by the toe resistance and soil resistance under the cap.

关 键 词：矩形闭合地下连续墙 桥梁基础 承载特性 模型试验 内摩阻力 承台土反力 

分 类 号：TU476.3[建筑科学—结构工程]