The Research On Reusable Support System Of Rectangular Working Pit

Aiming at the long construction period, complex process, high cost, great impact on the surrounding environment, low recovery rate and so on, which are more concentrated in traditional support type of rectangular working pit. In this paper, the structure design, strength check, numerical analysis, software and other means are carried out to design a set of supporting structure, which is assembled through a force transmission device, columns, supporting plate, connecting bolt and other structure unit. The supporting structure whose cross section size is 5m * 5m, the depth is not more than 5m is mainly applied to the small and short-term pit. The supporting structure meets basic strength, stiffness and stability, also has the advantages of convenient construction, short cycle, economy, environmental protection, high efficiency etc. In addition, the project compiles the corresponding software aiming to the set of supporting structure to information construction. In a word, the project wins time for the rescue and other emergency projects and provides reliable guarantee for the current and subsequent construction of city. Mainly do the following work:Firstly, the material of the rectangular pit multiplexing branch supporting system unified choice for Q235 steel structure unit. The vertical column can be buried to the expected depth through the force transmission device, air hammer or small drill into holes. Overall structure consists of several layers of support plate splicing into rectangular cross section through the connecting bolt layer by layer fixed on the upright column. This paper describes the structural type, working principle, assembling process and design theory of the support system. In view of the increasing of soil pressure, the thickness of support plate is optimized by using the method of stratified calculation. This paper, combined with engineering example, describes the design process of supporting system, and validates the rationality of stiffness and size design of column and size design of support plate according to the calculation value.Secondly, three-dimensional numerical simulation of the supporting system is carried out by means of the finite element software GTS NX, and the deformation of supporting plate, the deformation of the column and the settlement and uplift of the working pit are analyzed by taking into account the modeling conditions, unit selection form, boundary range, construction technology and other factors. The results show that maximum deformation of the supporting plate is approximately, maximum deformation of the column, raised and uplift values of working pit meets the design requirements, and the position of the maximum deformation value is in accordance with the actual situation, which further verifies the practical operability and engineering rationality in the application of working pit for the support system.Finally, using Visual Basic 2010 programming language develops a set of small software. This paper describes the software design process, and realizes the intelligence of soil parameter input, soil pressure value calculation and the thickness of sheet metal design, strength check of column, strength check of bolt, uplift force analysis, bottom stability checking. The software has been applied to the engineering example to verify its operability and accuracy.