两铰 Ｕ 型 钢－ Ｉ 字钢支 架集中梯 形支架与 Ｕ 型钢可 缩支架的 优点，并 采用 先进 的铰 接结构据现 场应用 观测结果 并通过 支架内力 计算，在 非对称载 荷作用 下，与 Ｕ 型钢 支架相 比，该 支架强度可 提高１ 倍 以上，可 缩性能改 善，避免 了支架构 件出现 破坏性变 形图５ ，表３ ，参３ Two-hinged U-steel - I-shaped steel bracket centralized trapezoidal stent and U-shaped steel retractable stent advantages, and the use of advanced articulated structure  According to field observations and calculated by the internal force of the stent, under asymmetric load, and U-shaped steel bracket Compared to the strength of the stent can be increased by more than 1 times, shrinkage can be improved to avoid the destructive deformation of stent components  Figure 5, Table 3, reference 3 