Experimental investigation of behavior of pile clusters in permafrost soils

Conclusions 1. The cluster effect depends on the state of the frozen soil; for hard-frozen soil it is manifested for a distance L2d between the piles, and for a plastic-frozen soil, for L 4d.2. For plastic-frozen soils account must be taken of the nonlinear creep settlement of the pile cluster, which is larger than the settlement of a single pile. The relation among the settlement, the number of piles in the cluster, and the distance between the piles has been established, and the corresponding method of analysis has been proposed.3. The load on the piles in the cluster is nonuniformly distributed, depending on the cap rigidity, the number of piles, the distance between them, and the state of the frozen soil. As a rule, the most loaded piles are those located farthest from the cap center, and the least loaded are those located inside the cluster.4. By applying the method of analysis of rigid plates on elastic bases of M. I. Gorbunov-Posadov, it is possible to analytically determine the loads on the piles in the cluster.Moscow Civil-Engineering Institute (MISI). Zabaikalpromstroniiproekt YaNIF Institute. Translated from Osnovaniya, Fundamenty i Mekhanika, Gruntov, No. 2, pp. 8–11, March–April, 1988.