| This paper focus on the dynamic effects of wall in excavation process, use the mechanical characteristics of retaining wall during different stages excavation in a circular artificial dig hole pile as the research object. By collecting large amounts of data, to road interchange engineering artificial dig hole pile foundation design and construction for the engineering background. By using the general finite element software ABAQUS to establish the three-dimensional model of the pile wall in the whole excavation construction stage of artificial digging hole, to explore the deformation force of the wall and the affected soil around the pile with the excavation depth, and considering the different soil parameters, different wall parameters, different excavation depth and other factors on the calculation and analysis of the influence, and to determine the sensitive degree of each influencing factor, the main conclusions are as follows:1、With the construction step of the wall structure, the change trend of favorable moment, shear force, horizontal displacement of each section of wall in every stage is connected, continuous. In the absence of lower excavation case, by retaining section just completed the bending moment, shear force minimum. The bending moment value of each section of wall in the upper 3/4 segment section wall is gradually increasing, and reached the maximum value decreased rapidly after 3/4 in the festival, the bottom moment values close to zero; the upper and lower ends of each section of wall under large negative shear value, and the lower end of the absolute value of shear values greater than the absolute values of the upper shear wall; with the increase of node number, vertical axis force maximum gradually down, the maximum axial force wall always appear in the 1/2 at the position of the whole structure of the wall.2、Each section of wall displacement maximum value appeared in its central 1/2 location, the minimum value appears in the top of each section of wall, the maximum horizontal displacement of the wall appear in the next section wall 1/2 position finally step completed, minimum at the surface position, And with construction steps the change value of displacement is smaller, Just completed the construction of the wall will occur larger horizontal displacement. Deep 18m artificial dig hole pile in the construction process, the vertical displacement of the ground surface excavation within 9m is given priority to uplift, when the excavation depth is more than 9m, the vertical displacement of the ground surface close to pile lateral soil is major settlement, and with the increase of construction excavation depth, the settlement value more and more.3、Change of soil heavy, friction angle of the soil parameters is the biggest influence on wall’s bending moment and shear value trend, the influence of the main parameters of retaining wall horizontal displacement variation of excavation depth is less than 8m for the soil modulus, the excavation depth is more than 8m for the friction angle.Wall stiffness and thickness parameters change, generally have not a greater impact on the wall stress and deformation tendency. Each section of wall excavation depth changes to the structure of the wall’s stress and deformation produced the greatest effect. Excavation of different depth, wall bending moment, shear force and the maximum horizontal displacement value is different, the position of the maximum is also different.Through the finite element analysis results, expected to supplement and improve the study of artificial dig hole pile wall, to guide and reference construction technology of this kind of project. |
PDF Full Text Request