基于裂后线性软化模型的钢筋钢纤维混凝土盾构管片应用研究  

Research on the Application of Steel Fiber Reinforced Concrete Segment in Shield Tunnelling Based on the Post-cracking Linear Softening Model

作　　者：李德明 董占武 温书亿 邓一三 LI Deming;DONG Zhanwu;WEN Shuyi;DENG Yisan(China Railway Academy Co.,Ltd.,Chengdu 610031;Qingdao Metro Group Co.,Ltd,Qingdao 266100)

机构地区：[1]中铁科学研究院有限公司,成都610031 [2]青岛地铁集团有限公司,青岛266100

出　　处：《现代隧道技术》2021年第1期148-153,共6页Modern Tunnelling Technology

基　　金：青岛地铁钢纤维管片应用技术研究(2017-KJ019-G001-SJ)。

摘　　要：通过开口梁三点弯曲试验研究了钢纤维混凝土的裂后塑性行为,选取了裂后线性软化模型作为盾构管片的材料模型,并在内力等效原则下,计算得到了由弹性弯拉残余强度表示的裂后线性软化模型下的塑性轴拉残余强度。通过截面静力平衡方程,引入塑性轴拉残余强度,得到了适用于大、小偏压条件下的钢筋钢纤维混凝土结构正截面承载力计算公式,完善了钢筋钢纤维混凝土管片的正截面承载力计算体系。通过管片全尺寸试验验证了材料模型和正截面计算方法的合理性。As a new type of composite building material,steel fiber reinforced concrete can make up for the short⁃comings of ordinary concrete such as low tensile strength and poor toughness,and thus has good engineering me⁃chanical properties,but its application lacks clear theoretical support.This paper studies the post-cracking plastic behaviors of steel fiber reinforced concrete through the three-point bending test of a notched beam.By adopting the post-cracking linear softening model as the material model of the shield tunnel segment,and based on the principle of internal force equivalence,the residual plastic axial tensile strength under the post-cracking linear softening mod⁃el is obtained,which is expressed by the residual elastic flexural and tensile strength.Through the sectional static equilibrium equation and the introduction of residual plastic axial tensile strength,the formula for calculating the normal section bearing capacity of steel fiber reinforced concrete structure is obtained,which is applicable to large and small eccentric compression conditions,improving the calculation system of the normal section bearing capacity of steel fiber reinforced concrete segments.Through the full-scale segment test,the rationality of the material model and the normal section calculation method is verified.

关 键 词：钢筋钢纤维混凝土 裂后线性软化模型 弹性弯拉残余强度 塑性轴拉残余强度 管片全尺寸试验 

分 类 号：U451.4[建筑科学—桥梁与隧道工程]