断裂影响下的高压钢筋混凝土岔管结构

Study on high-pressure reinforced concrete manifold structure under impact of fault

针对某断裂切割下的高压钢筋混凝土岔管结构,采用非线性有限元计算方法,分别从结构安全运行和围岩稳定性方面对开挖置换方案进行对比论证分析。计算结果表明:置换扩挖深度较小时,置换扩挖期的围岩开挖扰动位移以及塑性区的范围和深度均较小,围岩整体稳定性较好,但是运行期和检修期间钢筋混凝土岔管衬砌内的钢筋应力水平较高,局部难以满足结构安全运行需要;随着置换开挖深度的增加,扩挖施工期的围岩扰动位移有所增大,围岩塑性区范围和深度也均有所增大,而运行期和检修期的衬砌钢筋应力水平有所降低。

The comparative analysis and demonstration on the excavation replacement scheme for a high-pressure reinforced concrete manifold structure under the impact of the shear force from a fault are made herein in the aspects of beth the safety operation of the structure and the stability of the surrounding rock based on the nonlinear FEM. The calculation results show that when the depth of the enlarging excavation for the replacement is smaller, the depth and area of the disturbed displacement and the plastic zone in the surrounding rock during the enlarging excavation for the replacement are also smaller with a better integral stability of the surrounding rock, however the stress level of the reinforcement in the lining of the reinforced concrete manifold is higher during the operation and the inspection, and then can not meet the demand of the safety operation of the structure. Along with the increase of the depth of the replacement excavation, the disturbed displacement of surrounding rock during the replacement excavation increases somewhat, and then the depth and area of the plastic zone increase correspondingly, while the reinforcement stress level in the lining decreases relatively during the operation and inspection.