A New Type Of Sheet Pile Wharf Seismic Performance Evaluation And Liquefaction Hazard Protection Research

In our country, many areas are more suitable for the construction of digging into the basin, and sheet pile wharf can play to the investment province and the construction characteristics of fast speed, can produce a great social and economic effect. Therefore, the development of new high tonnage tons of deep water sheet pile wharf structure, is the need of the development of water transport business, is the need of regional economic development, is the needs of the development of terminal technology. For soil foundations, the earthquake liquefaction of sandy soil under the condition of the problem is a very important problem, damage to the structure may lead to be deadly, so we must study the high tonnage deep water sheet pile wharf structure resistance to vibration and shock absorption. This paper through three dimensional static and dynamic feedback analysis, simulated soil pressure and the phenomenon of the foundation of liquefied soil under earthquake load and study on the new working characteristic of the sheet pile under strong earthquake. We put forward a new type of sheet pile wharf earthquake scientific and reasonable safety evaluation method and evaluation standard. Then we can get the seismic method and shock absorption technology on the basis of deep water sheet pile wharf. The main content includes the following several aspects:1、Firstly to introduce the finite element method used in this paper, the control equation is based on Biot saturated sandy soil and establish the theory of the dynamic characteristics of soil and water coupling control equation, constitutive model is put forward by the OKA cyclic elasto-plastic constitutive.2、Simple sheet pile finite element model is established and we use it to compare with the shaking table test. We verified that the program can effectively simulate the saturated sand under earthquake dynamic of nonlinear and large deformation characteristics, at the same time, it can simulate sand liquefaction flow to the barrier of the pile and the front wall in pressure.3、In view of the existing preliminary data and geological data, to establish the finite element model of a sheet pile wharf unloading type, and it has carried on the preliminary simulation. Research shows that:under the action of earthquake, with the growth of excess pore water pressure ratio, the soil has the large deformation of horizontal flow, damage to the level of the front wall damage is greater than the vertical; The soil pore pressure change more violent with the grater seismic load; The soil pressure appears mutation at the junction of different soil layer; Unloading platform on the barrier on top of the pile displacement has a better coordinating role.4、Constructing a three dimensional finite element model to simulate this new type of sheet pile structure under strong earthquake working characteristic, and with the corresponding seismic measures after the model. Soil liquefaction speed increase quickly in this situation and the structure destroyed severely. When using a certain quantity of gravel pile, the third layer of sandy soil liquefaction degree had significantly lower, the structure of the seismic effect has a very obvious improvement.