| Given China’s constant economic and technological growth,many of the current river ship locks are reaching complete saturation.Ship lock expansion,at key navigation terminals,is absolutely required.It is common practice for new ship locks to be built adjacent to the original ship locks or existing dams and have a certain degree of impact on the existing ship locks.In this research,structural parameters of the double row diaphragm wall were analyzed with numerical simulation as the main research method.The Qingyuan new second line ship lock in Guangdong,China was chosen as the engineering case.The double row diaphragm wall is a major part of the braced supporting structure for the deep foundation pit for the new second line ship lock.Through the geotechnical finite element software MIDAS GTS NX,the structural parameters of the supporting structure were studied.The main contents and results from this paper are as follow:(1)Utilizing MIDAS GTS NX,a 3D finite element model of the new ship lock foundation excavation was constructed.The reliability of the finite element model was verified via comparison with the engineering monitoring data from the engineering case construction and survey unit.Cross comparison of the MIDAS GTS NX model was also performed with a model constructed in PLAXIS.(2)Based on the FEM model,the structural parameters of the double row diaphragm wall were studied through single factor sensitivity analysis.Their influences on the deformation and stress characteristics of the supporting structure,and displacement of the adjacent ship lock were analyzed.(3)Through orthogonal array testing and multiple finite element simulations,multi factor sensitivity analysis of the structural parameters was performed.The deformation and stress characteristics of the supporting structure and adjacent ship lock were analyzed to determine the influence of each structural parameter and a possibly more favorable set of parameters.(4)Based on the single and multiple factor sensitivity analysis,reference material of the most influential parameters for the design of future double row diaphragm wall supporting structures was provided.It determined that in order to reduce the overall deformation of the support structure and displacement of the adjacent ship lock,the thickness of the front diaphragm wall had larger influence.As an aside,wall spacing between the front and rear diaphragm wall had greater influence on the internal stresses of the support structure. |
