温缩作用下双层连续配筋混凝土路面配筋率设计参数对比分析

Numerical simulation of continuously reinforced concrete pavement with double⁃layer reinforcement under effect of temperature shrinkage

利用钢筋等效原理建立双层配筋CRCP在温缩作用下的数值模型并进行验证,在此基础上运用L50正交表设计数值仿真工况,以横向裂缝宽度bj、纵向钢筋应力极值σ_(s,max)和混凝土应力极值σ_(c,max)作为评价指标,对11项配筋设计参数进行敏感性分析和显著性排序。显著性分析表明,线膨胀系数、温降和配筋率、粘结刚度系数、钢筋弹性模量对CRCP力学响应影响较为显著,应作为双层配筋CRCP主要设计指标。在双层配筋CRCP的配筋率设计试算中,建议将配筋率ρ依次按照ρ∈[0.60%,0.80%]、ρ∈[0.80%,1.00%]、ρ∈[1.00%,1.20%]三个取值区间进行试算;将连续配筋混凝土(CRC)板体的1/3厚度处作为上层纵向钢筋和下层纵向钢筋的取值基点。

In this paper,the reasonable numerical model of CRCP with double-layer reinforcement under the action of temperature shrinkage is explored and verified.The error analysis and reliability analysis of the finite element calculation results and rectangular coordinate solutions are carried out to determine the reasonable analysis model.The L50 table was used to design the orthogonal test scheme of reinforcement factors,and the sensitivity analysis of design parameters affecting the reinforcement ratio of CRCP with double-layer reinforcement was carried out,and the influence law was studied.Through range analysis,variance analysis and significance evaluation,the sensitivity of each design parameter and the significance of the influence level are judged,the coefficient of linear expansion,temperature drop,reinforcement ratio,bond stiffness coefficient,and elastic modulus of steel rebars have significant effects on the mechanical response of CRCP with double layer reinforcement,and should be used as the main design indexes.It is suggested that the reinforcement ratioρaccording toρ∈[0.60%,0.80%]、ρ∈[0.80%,1.00%]、ρ∈[1.00%,1.20%]three value ranges for trial calculation;Take 1/3 of the thickness of CRC slab as the value point of longitudinal reinforcement.