回填施工对覆土波纹钢板拱桥受力性能的影响

Influence of backfilling construction on mechanical performance for soil-covered corrugated steel arch bridge

根据有限元软件和内蒙古某座拱桥参数,用beam3二维梁单元模拟波纹钢板,用plan42二维实体单元模拟回填土体,建立了考虑回填高度与拱圈相互作用的平面模型,计算了不同回填高度下的拱圈弯矩和轴力,分析了回填高度对拱圈应力和变形的影响。计算结果表明:在对称回填施工过程中,拱圈最大径向绝对位移约为0.9 mm,拱圈最大、最小应力分别约为10-、27 MPa;在不对称回填施工过程中,拱圈最大径向绝对位移约为1.4 mm,拱圈最大、最小应力分别约为12、-18 MPa,且最大径向绝对位移和最大应力均出现在拱圈右侧的1/8跨度附近。在回填施工过程中,应重点监控拱圈右侧1/8跨度附近拱圈的应力和变形。

On the basis of finite element software and the parameters of arch bridge in Inner Mongolia,2D beam element beam3 was used to simulate corrugated steel,2D solid element plan42 was used to simulate backfilling soil,and a plane model based on the interaction between backfilling height and arch ring was set up.The bending moments and axial forces of arch ring under different backfilling heights were calculated,and the influence of backfilling height on the stress and deformation of arch ring was analyzed.Calculation result shows that during symmetric backfilling construction process,the maximum radial absolute displacement of arch ring is about 0.9 mm,and the maximum and minimum stresses of arch ring are about 10,-27 MPa respectively.During asymmetric backfilling construction process,the maximum radial absolute displacement of arch ring is about 1.4 mm,the maximum and minimum stresses of arch ring are about 12,-18 MPa respectively,and the maximum radial absolute displacement and the maximum stress appear at 1/8 span on the right of arch ring.During backfilling construction process,the stress and displacement at 1/8 span on the right of arch ring must be mainly monitored.1 tab,15 figs,16 refs.