Shenzhen Subway Passed Through The General Merchandise Square Especially Big Load Pile Foundation Underpinning Engineering Research

Along with the increase of city subway construction in our country, it is becoming a new task to make people pay attention to reduce the possible influence on the old building from the subway construction.As a result of the planning requirement of the station position at the first-term subway project at Shenzhen, the tunnel on section passes through the merchandise square. The merchandise square construction is composed of 9-floor-above-ground and 3-floor-underground skirt building. The biggest underpinning load by pile foundation amounts to 18900 kN, which is the most layers of the underpinned floor and the biggest load underpinned by the single pile foundation at present in the world.Using the comprehensive technology of the domestic and the foreign related to underpinning technology of the pile foundation, mechanism and mechanical analysis of the project have been carried out in the thesis, which covers the model test of joint at pile-beam, field monolithic model test, construction technology and corresponding security measures. In addition, the monitoring and the measures to the neighboring buildings are also done. The merchandise square project with extra-big axial force underpinned by pile foundation has been successfully completed! The merchandise square project solved the contradiction between the subway line and the lively commercial buildings, which can be taken as the reference for the similar engineering. It has provided a broader space for route selection of the city subway. There are obvious technical, economic and social benefits.The thesis introduces the subway construction technology of pile foundation underpinning technology from the plan choice, main point of design, construction technology, structure monitoring and so on while the Shenzhen merchandise square is under the service.