Study of influence factors on tensile stress of top geogrid at the corner of reinforced earth retaining wall

Taking engineering examples as the background, using the numerical analysis software FLAC 3D, on the basis of the single-level vertical reinforced soil retaining wall with the angle of 90° in the wall, a three-dimensional numerical analysis model of reinforced soil retaining wall was established by changing the spacing of reinforcement, the length of reinforcement, and the method of auxiliary reinforcement. The tensile stress characteristics of the outer edge and corner bisector of the top geogrid of the irregular reinforced soil retaining wall under three influencing factors were compared and studied. The results show that the maximum tensile stress distribution of the geogrid at the corner shows an “X” shape, which is significantly different from the distribution law of the tensile stress of the geogrid at the straight position parallel to the wall, and the deformation is larger than that at the straight position. The tensile stress increases first andLMthen decreases with the increase of the distance from the corner (0-15 m), and the maximum is at 6 m, and the change is small after 15 m, that is, the stability of retaining wall design can be improved at about 6 m away from the corner in practical engineering; the spacing of the ribs and the way of the auxiliary ribs have obvious influence on the deformation of the geogrid, and the length of the reinforcement has little effect; When the spacing of the reinforcement is equal to 0.3 m, with the increase of the distance from the wall, the difference of tensile stress between the corner and the straight part is reduced, that is, the deformation degree of the corner is weakened and the stability of the retaining wall is improved. When the distance is less than 0.3 m, the reinforcement effect is not obvious, so the reinforcement spacing of 0.3 m is optimal. When the length of the reinforcement is 8-10 m, the deformation effect of the geogrid at the corner is better. When the auxiliary reinforcement is added as a whole, the corner of the middle and lower part of the wall is no longer the place where the tensile force of the geogrid is the largest, and the extension of the two sides of the corner along the wall is greater than corner. compared with the overall addition of auxiliary reinforcement, the control effect of half of the auxiliary ribs have a weak control effect on the deformation of the geogrid at the corner of the retaining wall, but it can play a good control role and also save materials, and the specific application depends on the actual situation; In practice, the deformation of the geogrid can be controlled by changing the spacing of the reinforcement or adding auxiliary reinforcement, and the distance between the auxiliary reinforcement and the main reinforcement has little effect on the reinforcement effect.