钢筋混凝土空心墩延性变形能力分析

基于纤维梁柱单元建立钢筋混凝土空心墩滞回分析模型,与试验结果对比验证模型准确性。在此基础上讨论纵筋配筋、壁厚、混凝土强度、剪跨比等因素对空心墩延性变形能力影响。研究表明:对剪跨比大于7.0的高墩,提高纵筋配筋率可有效增强其延性变形能力;而对于剪跨比小于5.0的中低墩,提高纵筋配筋率对其延性变形能力不利;在轴压比和纵筋配筋率一定情况下,空心墩壁厚对其延性变形能力影响不大,而保持轴力和纵筋配筋量不变时,增大壁厚可有效增加中低墩延性变形能力;且在固定轴力下,增大混凝土强度对提高中低墩延性变形能力效果显著。

Analysis on Ductile Deformability of Hollow Reinforced Concrete Bridge Piers

The hysteretic analysis model of hollow reinforced concrete bridge piers was established on the basis of fiber beam-column elements and the accuracy of the model was verified by comparison with reliable experimental results.The influences of the longitudinal reinforcement,wall thickness,concrete compression strength and aspect ratio on the ductile deformability of hollow bridge piers were studied.It is found as follows: With high piers with the aspect ratio larger than 7.0,the ductile deformability can be effectively increased by raising the longitudinal reinforcement ratio;with low-height and medium-height piers with the aspect ratio less than 5.0,raising the longitudinal reinforcement ratio is unfavorable for the ductile deformability;the wall thickness has little influence on the ductile deformability of hollow piers with constant axial load ratios and longitudinal reinforcement ratios,however,when keeping the axial load and longitudinal reinforcement unchanged,pier wall thickening will better the ductile deformability of low-height and medium-height piers effectively;also,it is effective to increase the ductile deformability of low-height and medium-height hollow bridge piers by using high-strength concrete under constant axial loads.