In recent years, the deeply-embedded large-diameter cylindrical structure has been widely used in the construction of ports and cross-sea passages in soft soil under deep water in China. However, the effect of strain softening of soft soil on the bearing capacity of the structure has not been studied systematically. By introducing the attenuation law of soft soil strength with the accumulation of plastic strain into the ideal elastic-plastic model based on the Tresca yield criterion, the lateral capacity of the deeply-embedded cylindrical structure in soft soil was analyzed. The results show that the bearing capacity of the large cylinder structure reduces significantly when the strain softening effect of the soft soil is considered, and the sensitivity, relative ductility and reinforcement range of the soft soil have a great influence on the lateral capacity of the structure. The failure mechanisms of the large cylinder under horizontal loading change from a double-sided failure mode before reinforcement to a single-sided failure mode after reinforcement.
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