Composite soil nailing wall composed by micro-pile and waterproof curtain is a frequently used type of supporting structure in foundation pit engineering. But the collocation of micro-pile and waterproof curtain in the design and construction of supporting structure is random. And the influence of different locations of micro-pile

like in front of or behind curtain

on mechanical behaviors of supporting structure is generally neglected. This article obtains deformation and mechanical characteristics

such as the displacement of supporting structure

axial force of soil nailing

in those two collocations through the contrastive analysis of the field test and numerical simulation based on a certain foundation pit project in Jinan. The analysis results show that the overall trend of deformation and internal force of supporting structure isn’t affected by different location of micro pile. And the difference caused by the location of micro-pile without top load is small; but the deformation of supporting structure is smaller and the stress of soil nail is more reasonable when micro pile is behind curtain under top load. And it can be suggested to preferentially adopt in practical engineering.