煤炭技术

综采过程中，液压支架立柱在偏载条件下易出现受力不均和应力集中，严重影响支撑稳定性和寿命。以ZY21000/36/75D型液压支架为工程对象，建立其低位偏载工况下刚柔耦合仿真模型，基于仿真结果构建顶梁和立柱的空间力系模型，推导方程组求解立柱受力，对偏载侧立柱进行双向流固耦合分析，依据循环加载疲劳寿命准则优化立柱结构。研究表明：低位偏载工况下，2个立柱受力的最大值分别为8.122 1 MN和18.960 0 MN，立柱缸体最大应力713.08 MPa，进油孔出口处有应力集中，最大应力791.73 MPa。通过优化，将最低寿命从16 909次提高至23 157次。研究结果对提高立柱使用寿命具有重要意义。

During the fully mechanized mining process, the hydraulic support columns are prone to uneven stress and stress concentration under eccentric loading conditions, which seriously affects the stability and service life of the support. Taking the ZY21000/36/75D hydraulic support as the engineering object, a rigid-flexible coupling simulation model under low-position eccentric loading conditions is established, based on the simulation results, a spatial force system model of the top beam and columns is constructed, and a set of equations is derived to solve the forces on the columns, a bidirectional fluid-structure coupling analysis is performed on the columns on the eccentric loading side, and the column structure is optimized based on the cyclic loading fatigue life criterion. The research shows that under low-position eccentric loading conditions, the maximum forces on the two columns are 8.122 1 MN and 18.960 0 MN, respectively, the maximum stress on the column cylinder is 713.08 MPa, and there is stress concentration at the oil inlet outlet, with a maximum stress of 791.73 MPa.Through optimization, the minimum service life is increased from 16 909 cycles to 23 157 cycles. The research results are of great significance for improving the service life of the columns.