CAJ | 학술논문

针对基坑支护设计和施工中对立柱隆起危害认识不足的问题，通过理论分析，提出考虑立柱隆起影响的钢支撑承载力计算方法。运用实测数据，从正常施工、超挖及基坑放置过长时间3个工况分析了立柱隆起对钢支撑体系的影响，并进一步分析了单根支撑破坏后支撑体系的响应。研究表明：钢支撑承载力随立柱隆起的增大而明显减小；设计轴力越大，允许的立柱竖向位移越小；最后一层土开挖是风险最高节点，倒数第二道是相对最薄弱的支撑；超挖会引起已安装钢支撑的轴力明显增加，危及支撑稳定；基坑长时间放置，立柱持续隆起将威胁到钢支撑的安全，每层土放置时间长短将影响各道支撑进入失稳状态的顺序；最薄弱钢支撑一旦失稳破坏将引发支撑体系“多米诺”骨牌效应，造成该处挡墙整体垮塌或断裂；所用的分析方法，可用于钢支撑体系设计和施工过程中实时判定钢支撑体系的安全性状。
침대기갱지호설계화시공중대립주륭기위해인식불족적문제，통과이론분석，제출고필립주륭기영향적강지탱승재력계산방법。운용실측수거，종정상시공、초알급기갱방치과장시간3개공황분석료립주륭기대강지탱체계적영향，병진일보분석료단근지탱파배후지탱체계적향응。연구표명：강지탱승재력수립주륭기적증대이명현감소；설계축력월대，윤허적립주수향위이월소；최후일층토개알시풍험최고절점，도수제이도시상대최박약적지탱；초알회인기이안장강지탱적축력명현증가，위급지탱은정；기갱장시간방치，립주지속륭기장위협도강지탱적안전，매층토방치시간장단장영향각도지탱진입실은상태적순서；최박약강지탱일단실은파배장인발지탱체계“다미낙”골패효응，조성해처당장정체과탑혹단렬；소용적분석방법，가용우강지탱체계설계화시공과정중실시판정강지탱체계적안전성상。
Aiming at the lack of recognition of the serious problem about column uplift in the excavation supporting design and construction,the steel support bearing capacity calculation method on the consideration of the influences of column uplift was con-structed based on theoretical analysis.Accordingly,the influence of column uplift of steel supporting system from three condi-tions was analyzed as the normal construction,overbreak and excavation placed for a long time by using the measured data.The influence of the supporting system after single support damage was then discussed.As is shown in the experiment,steel support decreases obviously along with the increase of column uplift bearing capacity.The greater design of the axial force is,the smaller axial displacement allows.The last layer of soil excavation is at highest risk nodes,while the penultimate layer is a relatively weak support.Overbreak causes significant increase of axial force of installed steel support which threatens the supporting stabili-ty.With the longer placement of excavation,the continuous column uplift threatens the safety of steel support;the length of placement of each layer of soil will affect the order of the support instability.Once the weakest steel support is damaged,it will cause dominoes effect of the supporting system and lead to the overall collapse or fracture of the retaining wall.The analyzing method in this paper is available for real-time decision of safe state of steel supporting system in the process of design and con-struction.