斜交条件下预制拼装地道结构设计研究

以上海S7公路一期工程斜交条件下的下穿地道为例,对纵缝采用凸凹榫接头的预制拼装体系与封闭框架的现浇工艺体系进行结构受力对比,结果发现,设计中通常假定凸凹榫处采用铰接进行模拟存在不合理之处.因此,从方便工程设计的角度出发,提出预制拼装斜交地道结构体系的受力计算模型可考虑利用封闭框架体系的等效计算模型,但需将凸凹榫位置处的内力值适当提高20％～30％.该研究成果已在依托工程成功应用,可以为类似工程提供参考与借鉴.

Study on Structure Design of Prefabricated Tunnel under Oblique Crossing Condition

Taking an underpass under the oblique crossing condition of Shanghai S7 Highway Phase I Project as an example, the structural stress of the prefabricated assembly system with convex-concave tenon joints and the cast-in-place technological system with closed frame for longitudinal joint is analyzed and compared. In design, it is usually assumed that the simulation of the convex-concave tenons with hinge joints is unreasonable. Therefore, from the perspective of convenient engineering design, it is proposed that the equivalent calculation model of closed frame system can be considered in the stress calculation model of prefabricated oblique crossing tunnel structure system, but the internal force value at the position of convex-concave tenons should be appropriately increased by 20%~30%. This study result has been successfully applied in the supporting projects, which can be referred for the similar projects.