西南交通大学学报
西南交通大學學報
서남교통대학학보
JOURNAL OF SOUTHWEST JIAOTONG UNIVERSITY
2014年
2期
254-259
,共6页
施工期隧道%型钢钢架喷混凝土%徐变%结构安全性%位移方法
施工期隧道%型鋼鋼架噴混凝土%徐變%結構安全性%位移方法
시공기수도%형강강가분혼응토%서변%결구안전성%위이방법
tunnel under construction%steel reinforced shotcrete%creep%structural safety%displacement-based method
针对施工期隧道型钢钢架喷混凝土支护,建立了以位移为基础的安全性评价方法。介绍了根据喷混凝土徐变试验得到的修正的GL2000徐变模型,给出了徐变引起的支护轴向伸缩变形和曲率改变的计算公式。导出了基于测量位移并考虑徐变影响的支护内力的计算公式,给出了支护结构截面失效的功能函数。最后,对武广铁路某隧道工程进行了实例分析。计算结果表明:评价结果能够正确反映隧道的实际安全状态,可靠指标的数值与我国现行规范的规定一致;徐变使喷层产生松弛,可靠指标增大,但其增大幅度比素喷混凝土和格栅钢架喷混凝土时小。
針對施工期隧道型鋼鋼架噴混凝土支護,建立瞭以位移為基礎的安全性評價方法。介紹瞭根據噴混凝土徐變試驗得到的脩正的GL2000徐變模型,給齣瞭徐變引起的支護軸嚮伸縮變形和麯率改變的計算公式。導齣瞭基于測量位移併攷慮徐變影響的支護內力的計算公式,給齣瞭支護結構截麵失效的功能函數。最後,對武廣鐵路某隧道工程進行瞭實例分析。計算結果錶明:評價結果能夠正確反映隧道的實際安全狀態,可靠指標的數值與我國現行規範的規定一緻;徐變使噴層產生鬆弛,可靠指標增大,但其增大幅度比素噴混凝土和格柵鋼架噴混凝土時小。
침대시공기수도형강강가분혼응토지호,건립료이위이위기출적안전성평개방법。개소료근거분혼응토서변시험득도적수정적GL2000서변모형,급출료서변인기적지호축향신축변형화곡솔개변적계산공식。도출료기우측량위이병고필서변영향적지호내력적계산공식,급출료지호결구절면실효적공능함수。최후,대무엄철로모수도공정진행료실례분석。계산결과표명:평개결과능구정학반영수도적실제안전상태,가고지표적수치여아국현행규범적규정일치;서변사분층산생송이,가고지표증대,단기증대폭도비소분혼응토화격책강가분혼응토시소。
A displacement-based method was proposed to evaluate the safety of steel reinforced shotcrete support for tunnels under construction. Based on shotcrete creep experiment,a GL2000 model was modified and employed to describe the creep of shotcrete. Formulas to calculate the axial deformation and curvature change of the support were obtained. Formulas to compute the internal forces of the support with creep considered were given,and performance functions to a cross-section of the support were put forward. At last,a case study was done for a tunnel on the Wuhan-Guangzhou railway line. The case research result shows that results based on the proposed method are consistent with in-situ situations. Calculated reliability indices fall into the interval required by the related Chinese codes. Creep causes the shotcrete to relax to result in large reliability indices,but the increase of the indices is smaller than those for plain shotcrete and lattice girder reinforced shotcrete supports.