Surfacing prevention method of the flying prevention structure and manhole manhole

摘要

PPROBLEM TO BE SOLVED: To provide an uplift preventing method of a manhole and the uplift preventing structure to prevent the uplift even when a liquefaction phenomenon is caused or a groundwater level is elevated by an earthquake or the like. PSOLUTION: An overhang part (2) is formed on an outer peripheral part of the manhole (1) having a bottomed cylindrical structure. An uplift preventive body (3) covering the overhang (2) is placed around the manhole (1) at a predetermined depth. The uplift preventive body (3) has a predetermined unit weight, and has a pressure receiving surface (32) having a predetermined upper profile area. The manhole (1) is prevented from being uplifted because of the weight of the uplift preventive body (3) and the force applied to the pressure receiving surface (32). PCOPYRIGHT: (C)2008,JPO&INPIT