直墙半圆拱形钢管混凝土支架力学性能实验及应用

为研究直墙半圆拱形断面巷道面临的支护难题,设计了直墙半圆拱形钢管混凝土支架与U型钢支架力学性能对比实验;实验全面测试并分析了钢管混凝土支架的承载力、位移与应变,同时分析了热煨弯曲对钢管原材料抗拉性能的影响及C60混凝土配合比合理性;实验证明钢管混凝土支架具有突出的承载优势。在实验指导下,对华丰矿-1100水平大巷动压巷道和大淑村矿-450水平新东翼皮带巷高应力集中巷道做了直墙半圆拱形钢管混凝土支架支护设计并应用,实践证明钢管混凝土支架支护效果明显,优于同断面U型钢支架,同时也发现直墙半圆拱形封闭支架的底角为薄弱点,并进行了改进与结构强化。

Experiment on Mechanical Property of Straight-wall Semicircle-arch Concrete-filled Steel Tube Support and its Application

Mechanical property experiment is designed to compare the performance of straight-wall semicircle-arch concrete-filled steel tube support and that of U-shaped steel support, so as to solve the instability problem of the support for roadways with conventional straight-wall semicircle-arch cross-section. In the experiment, the load bearing capacity, displacement and strain of the concrete-filled steel tube support are measured and analyzed, and the influence of the roasted bend on the anti-tensioning property of the raw material of the steel tubes, as well as the rationality of the mixing ratio of the C60 concrete, are analyzed. The experiment shows that the concrete-filled steel tube support has outstanding load-bearing advantages. Guided by the experiment results, straight-wall semicircle-arch concrete-filled steel tube support is designed and applied for the 1100 horizontal dynamic pressure roadway of Huafeng coal mine and the 450- level new east wing high stress roadway of Dashueun coal mine. The practice shows that the concrete-filled steel tube support has good supporting effect and is superior to the U-shaped steel support with the same profile. It is also found that the foot corners of the closed straight-wall semicircle-arch support are weak points and need to be improved and strengthened.