上埋式拱涵应变分布特性及有限元分析

为研究高填路堤下涵洞的病害机理,对上埋式拱涵的应变分布特性进行了研究。通过对现场某实际拱涵应变的观测和有限元分析,在计算结果与工程实测吻合较好的条件下,得到了拱涵的应变分布特性。结果表明,在拱涵涵顶下部的拉应变最大,侧墙上部的应变较大,上拱45°位置的应变较小;填土荷载产生的混凝土裂缝最易在涵洞顶端下部出现,需补强。埋入EPS不仅能减小涵顶的最大竖向土压力,而且能全面改善涵拱结构的应变分布状况,从而改善涵洞断面混凝土的受力,能大幅降低涵洞混凝土的应变状态。

Strain Distribution Properties of Positive Buried Arch Culvert and Its Finite Element Analysis

In order to study the distress mechanism of culvert under embankment of high-stacked soil,the strain distribution properties of positive buried arch culvert was analyzed.Observation in situ and FEM analysis of actual arch culvert were carried out,and the calculation results were agreed with the experiment data well.The results show that(1) the tensile stain at the bottom of the top arch culvert reaches the maximum,the stain at the upside of the sidewall is medium,and the stain at the 45 degrees of the arch is the minimum;(2) cracks caused by the high-stacked soil appear in the bottom of the top arch primarily,this position requires special reinforcing.The vertical soil pressure on the top of the culvert can be reduced greatly if EPS embedded,and the strain distribution of the culvert structure can be ameliorated ultimately,thus the stress of the culvert concrete can be reduced.