摘要
针对用于上海污水外排的黄浦江底隧道工程，通过土工离心模拟试验，探讨了上海粘土的成拱能力。对于无支护的情况，开挖双孔隧道时，洞底以上约８ｍ厚的灰色砂质粉土或粘土中不能形成稳定的天然拱。进一步研究表明，该层土所需的成拱厚度至少为１２ｍ；对于有混凝土管支护的情况，由于支护刚度较大。
This paper discusses the arching capacity of Shanghai clay by a series of centrifugal model tests modeling the drainage tunnel under the Huang Pu River.When the double-cave is excavated at the same time with non-supporting,the fifth clay layer with a thickness of 8 meters is not able to produce soil arching. Further research indicates that the arching thickness of the fifth clay layer is at least 12 meters;if the tunnel is supported by concrete pipes,and the stiffness of supporting is very high,the pressure on the pipes is equal to the total weight of the soil above the pipe.
