Influence of shear deformation on deflection of box girder with corrugated steel webs
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摘要: 波形钢腹板箱梁是一种新型的钢-混凝土组合结构, 与传统混凝土腹板箱梁相比, 其挠度计算中剪切变形的影响是不可忽略的。结合波形钢腹板箱梁的结构特点并应用初等梁理论, 提出该种箱梁受弯时考虑了剪切变形影响的挠度计算方法, 通过模型试验和有限元分析进行了验证; 同时指出不同剪跨比, 剪切变形对箱梁挠度的影响是不同的, 并就考虑剪切变形影响与否的剪跨比界限值提出建议.Abstract: The box girder with corrugated steel webs is a new type of composite steel concrete structure. Compared with conventional box girders with concrete webs, the influence of shear deformation may be not ignored in its deflection calculation. Combining structural properties of box girder with corrugated steel webs and the theory of elementary beams, a calculation method of its deflection under flexure, which considers the influence of shear deformation on it, is provided. The results of model tests and finite element analysis further testify it. With different shear span ratios, the influence of shear deformation on the box girder deflection is different, thus a limit value of shear span ratio is suggested for considering the influence of shear deformation or not.
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Key words:
- box girder with corrugated steel webs /
- shear deformation /
- deflection /
- shear span ratio
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表 1 简支波形钢腹板箱梁的跨中挠度
Table 1. Tab.1 Midspan deflection of simply supported box girder with corrugated steel webs
荷载等级/kN 5 10 15 20 25 不考虑剪切变形时的计算值(即仅由弯矩产生的挠度) /mm 0.10 0.19 0.29 0.38 0.48 考虑剪切变形时的计算值/mm 0.18 0.36 0.54 0.72 0.90 试验实测值/mm 0.11 0.24 0.41 0.56 0.70 有限元计算值/mm 0.13 0.26 0.39 0.52 0.65 注: 表中试验实测值为两根梁挠度的平均值。 表 2 剪跨比变化时简支波形钢腹板箱梁跨中挠度
Table 2. Tab.2 The midspan deflection of simply supported box girder with corrugated steel webs when shear span ratio variates
剪跨比 1/10 1/15 1/20 1/25 1/30 不考虑剪切变形时理论计算值(1) /mm 0.94 3.17 7.51 14.66 25.35 考虑剪切变形时理论计算值(2) /mm 1.46 3.96 8.56 15.98 26.87 有限元计算值(3) /mm 1.51 4.28 8.84 15.13 27.23 [ (2) - (1) ]/ (1) /% 55 25 14 9 6 [ (3) - (1) ]/ (1) /% 61 35 18 11 7 注: 表中最后两行数据为剪切变形引起的挠度占弯矩产生的挠度的百分比。 -
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