Abstract: To realize reinforcing cage construction of underground diaphragm in narrow and complex construction site, a new type of underground diaphragm wall reinforcement is put forward, which is named as pilewall. In this paper, the formula of the pilewall design method is deduced, the construction process is simulated and compared with the monitoring results. Finally, the design method of pilewall structure is formed, and the advantages and disadvantages of piletype wall structure, traditional underground diaphragm structure, and shelter pile structure are comparatively analyzed in terms of bending capacity. The results show that compared with the traditional underground diaphragm structure, the pilewall structure needs 1.27~1.58 times of steel bars, which ensures a significant improvement in flexibility during construction and provides guidance and reference for the design and construction of deep foundation pit retaining structure in narrow or complex sites.

Key words: foundation pit, retaining structure, pilewall, underground diaphragm wall, shelter pile, numerical simulation, monitoring, deformation