室内地下空间基础补偿原理初探

COMPENSATION METHOD APPLIED FOR CONSTRUCTION OF BASEMENT NESTED IN EXISTING BUILDING

讨论将补偿基础用于室内建造地下空间的原理与方法,提出考虑活荷载影响的室内地下空间补偿原理及相应的活荷载地基应力影响系数,根据该原理,增建地下室新增荷载将被基坑开挖移去的土重和以地坪活荷载影响为主的先期固结压力的一部分所补偿。初步研究和应用实例显示,将补偿法应用于既有建筑室内地下空间开发是可行的,适当控制开挖深度和新增荷载,室内基坑开挖和地下空间建造引起的地基扰动和变形可以被控制在较小范围内,从而降低对既有建筑造成损害的风险。

The principle of constructing basement nested in existing building is discussed. A indoor compensation method that compensates foundation worked expectedly under the influence of live loads on floor,and the coefficient confirmed to calculate foundation soil stress by multiplying live loads on floor are presented. Based on the proposed principle,the total loads of the underground space to be built can be balanced and compensated by the summary of no less than the following parts:one is the soil weight of foundation pit;the other is a part of the pre-consolidation pressure which mainly comes from the soil stress of floor live load. A construction case is illustrated. The research results and the engineering practice both show that the indoor compensation method was suitable to applying to constructing basement nested in existing building. As the excavation depth and the increased loads was determined according to the method,the foundation soil deformation affected by the indoor excavation and construction would no longer threaten existing building?s stability and would reduce the risk of damage to the existing building.