Experimental investigation on the lateral bearing behavior of lattice-shaped diaphragm wall with double-layer configuration

This paper delves into the lateral load-bearing behavior of lattice-shaped diaphragm wall (LSDW), a
novel type of diaphragm wall foundation with many engineering advantages. By employing a double-layer wall structure for the first time in laboratory settings, the research presents an innovative testing methodology, complete with novel computational formulas, to accurately measure the responses of LSDW’s inner and outer walls under varying loads. It is found that the Q–s curves of LSDWs exhibit a continuous, progressive deformation and failure characteristic without any abrupt drops, and the standard for judging the horizontal bearing capacity of LSDW foundations should be based on the allowable displacement of the superstructure. The bearing capacity for the double-chamber LSDWs was found to be approximately 1.68 times that of the single-chamber structure, pointing to a complex interplay between chamber number and structural capacity that extends beyond a linear relationship and incorporates the group wall effect. The study also reveals that LSDWs act as rigid bodies with minimal angular displacement and a consistent tilting deformation, peaking in bending moment at about 0.87 of wall depth from the mud surface, across different chamber configurations. Furthermore, it can be found that using the p–y curve method for analyzing the horizontal behavior of LSDW foundations is feasible, and the hyperbolic p–y curve method offers higher accuracy in calculations. These insights offer valuable guidance for both field and laboratory testing of LSDWs and aid in the design and calculation of foundations under horizontal loads.