Summary: | 碩士 === 國立臺北科技大學 === 土木與防災研究所 === 94 === Among today’s researches, feW of them involve the ground settlement resulted by the construction of diaphragm Wall. As a matter of fact, according to the monitoring data in domestic and foreign cases, the maximum ground settlement resulted by the construction of diaphragm Wall may account for 30%-50% of the total settlement. There are many factors may affect such settlement, most of them are difficult to control.This study use finite element softWare PLAXIS 3D,to analysis ground settlement and panel stability under construction of diaphragm. In the first, the parametric study is use to evaluate mesh gradient, research steps and geoeogy boundary. Secondy the numerical ressulte is compared With field monitoring data and also verifield accuracy of finite element method .
The lateral earth pressure is smaller than earth pressure at rest during B1~B3 excavation stage, this is called the active state. At C1~C2 stage, the lateral earth pressure is larger than rest earth pressure. This is called the return to mostly passive state of ground. According to the results of panel stability analyses, the satety facter is grasdually loWer at B1~B3 excavation stage, and then returning to safe side at concreting stage. This study is also evaluated the influence facters at construction of diaphragm Wall of soil deposit in Taipei basin. It is founed that, the unit thickness W and unit depth D of diaphragm Without any. The unit length , grountWater level difference △h, Working load and construction stage and have great influence to panel stability.
Finally, the study decided the influence range of diaphragm excavation stage of soil deposit in Taipei basin. In x direction, the influence range is 12meters (2L)at the centre of unit panel.In z direction,the influence range is 25 meters (5/6D)at the centre of unit panel otherWise,in z direction,the influence range is 30 meters(5/4 panel length).In x direction,the influence range is 35 meters(7/6 panel depth).
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