1.School of Transportation and Civil Architecture,Foshan University;2.China
In view of the wide application prospect of double row piles under complex surrounding environment and the complex mechanical behavior of double row piles, based on the principle of similar material model test, a laboratory test model for double row piles of deep foundation pit is built. The bearing characteristics of double-row piles under five reinforcement conditions, including inter-pile soil, passive zone at pile side, soil at pile end and composite reinforcement, are analyzed and studied. The results show that the maximum positive and negative bending moments of front row piles are 66.9% and 55.3% lower than those without reinforcement measures, while the maximum positive and negative bending moments of back row piles are 98.3% and 56.0% lower respectively, while the horizontal displacement of top piles is 77.3% lower. The bearing capacity of double-row piles can be effectively improved by soil reinforcement between piles, passive zone at pile side and soil reinforcement at pile end, but the effect of soil reinforcement between piles is the best. The main reason is that soil reinforcement between piles can significantly improve the deformation modulus of soil between piles, thereby enhancing the overall flexural rigidity of the cross-section of pile-soil composite bearing body, thereby improving the bearing capacity of double-row piles.