The aim of this study is to design economically foundations which are subjected to large lateral forces such as unsymmetrical earth pressure or seismic inertia force of superstructure by using grid form soil improvement wall used as liquefaction prevention of soft ground. The proposed way is to add dents and bumps to the head of the soil improvement and unite concrete foundation with it for lateral force transmitting. Lateral resistance of the joint is studied theoretically and experimentally. The results show the performance of the joint is more than 1.5 times larger than the no dent and bump joint under same contact pressure and the proposed calculation formula is valid.