关键词: 钢管混凝土支架, 平衡极限理论, 轴压试验, 数值模拟

Abstract: Steel tuber confined concrete (STCC) supports, as a new support form, has been gradually applied in underground roadway support. In this paper, the mechanical properties of STCC supports were comprehensively analyzed by theoretical analysis, laboratory tests and numerical simulations. Based on the ultimate bearing capacity (UBC) formulas of STCC axial compression short columns, UBC of short column can reach 1 115.5 kN, which is greater than the UBC sum of the hollow steel tube and plain concrete short column. In the support loading test, the support is affected by pole instability duo to loading constraint conditions, while the strengths in various parts of support are different, which leads to the fact that UBC of the tested supports is 1.35 times than that of short column. In numerical simulation of roadway model supported by circular STCC supports, both the yield load and ultimate load of supports are over 2 times of the UBC value of short-column．In addition, large plastic deformations of supports have been produced, and the deformation rate is close to 9%. Therefore, duo to the high bearing capacity of STCC supports, as well as the advantages of large deformation and yielding support, it is particularly suitable to be applied in soft rock roadway support and deep roadway support.

Key words: steel tuber confined concrete supports, limit equilibrium theory, axial compression test, numerical simulation