混凝土基础筏板抗裂设计验算中的若干问题  

SOME PROBLEMS FOR CRACK CHECKING IN DESIGN OF REINFORCED CONCRETE RAFT FOUNDATION

作　　者：潘立[1] 

机构地区：[1]中国建筑科学研究院建筑结构研究所,北京100013

出　　处：《工业建筑》2015年第8期116-120,144,共6页Industrial Construction

摘　　要：为确保混凝土筏基的抗裂性能满足结构的耐久性、地下结构的抗渗漏性及外观质量要求,有必要按相关技术标准的要求验算并控制裂缝最大宽度。目前结构设计中,对允许带裂缝工作的混凝土筏基,通常主要凭经验预留温度后浇带控制裂缝,而较少按最不利工况验算裂缝最大宽度,或验算条件与内力组合有误,这是近年常见混凝土筏基局部裂损的重要原因。基于技术分析,结合实际工程设计复核,对混凝土筏基抗裂验算中的组合拉应力、地下水浮力作用、裂缝宽度控制标准、温度后浇带效能等诸问题进行研究和讨论。To ensure the anti-crack performance of reinforced concrete raft foundations that can meet structural durability,anti-leakage and appearance of basements,it is necessary to check and control the maximum width of crack according to relative technical codes. In structural design right now,for these raft foundations which were allowed in use with controlled cracks,it was mainly the reason that cracked raft foundation cannot be used normally because thermal post-cast band was selected on the whole only depending on experience,and less calculation checking was taken for the maximum width of crack under the most unfavorable case,or wrong checking case was chosen in design. Based on technical analysis and practical design review for the raft foundation in basements,some concerned problems were studied and discussed,such as combination concrete tensile stress,reaction force of raft underside from groundwater buoyancy,acceptable maximum crack width,efficiency of post-cast band.

关 键 词：混凝土筏基 抗裂控制 裂缝最大宽度验算 组合拉应力 地下水浮力 温度后浇带 

分 类 号：TU471.15[建筑科学—结构工程]