南水北调中线工程的大型倒虹吸一般采用深埋式, 在冬季停运期, 倒虹吸内表面边界条件属于第三类边界条 件, 通过引入虚边界, 对第三类边界条件做了近似处理, 并简化温度场, 由应力自平衡和力法分别推导出了横向非线 性温度自约束应力和框架约束应力, 整合这两部分温度应力, 得到倒虹吸横向温度应力简化计算公式。对勒马河倒 虹吸的计算结果显示, 在冬季停运期, 其内表面会产生2 M Pa 的拉应力, 而且板厚越大, 内表面的拉应力越大, 对温 度应力控制不利。

The lar ge inv erted siphon in the Middle Route of South2t o2Nor th Water Tr ansfer Pr oject is usually bur ied. In w inter dow ntime, the inner surface bo unda ry conditio n belo ng s t o the third2type boundar y conditio ns. Virtual boundar y was intr oduced to perform the approx imate tr eatment on the third2type bo undary conditio ns, and temper ature field was simplified. Acco rding to the self2balance o f str ess and fo rce metho d, the tr ansv erse no nlinear thermal self2const raint stress and framew or k constraint st ress w ere derived. Integr ation of t he tw o therma l stresses can pro vide the simplified formulas of tr ansv erse thermal stress of inverted sipho n. The formula was applied to Lema River inverted sipho n. The results show ed that dur ing the winter dow ntime, the tensile str ess o f 2 MPa occur s at the inner surface, and the t ensile st ress at the inner surface is larg er w hen the slab thick2 ness is higher, which is unfav or able to thermal stress contro l.

长江学者和创新团队发展计划资助( IRT 1139)