赵均海 侯玉林 张常光

摘 要：对于新提出的方形高强钢管混凝土叠合柱的极限承载力，基于统一强度理论，考虑中间主应力和材料拉压比的影响，引入有效约束系数和非有效约束系数并考虑箍筋对钢管外混凝土约束作用的不同，把钢管外箍筋约束混凝土划分为有效约束区和非有效约束区，将方形截面等效为圆形截面以考虑钢管核心混凝土受到的钢管和外围钢筋混凝土的双重约束效应，提出了方形高强钢管混凝土叠合柱的一种新的轴压极限承载力计算方法。将所得理论计算结果与文献试验结果进行对比，吻合良好，证明了公式的正确性。对各参数的影响规律分析表明，方形高强钢管混凝土叠合柱的承载力随着侧压系数、中间主应力影响系数、材料拉压比和纵向配筋率的增大而增大，随着钢管径厚比的增大而减小。

关键词：钢管混凝土叠合柱；箍筋约束；强度理论；极限承载力

中图分类号：TU312；TU398

文献标志码：A文章编号：1674-4764（2016）05-0020-07

Abstract：Based on the unified strength theory and the influences of intermediate principal stress and the material of tension and compression ratio were considered when coming down to the ultimate bearing capacity of square steel tube-reinforced high strength concrete column. Effective constraint coefficient and ineffective constraint coefficient were introduced to consider the different constraint functions of concrete derived from the stirrups， the constraint concrete outside steel tube was divided into effective constraint region and ineffective constraint region. The square section was equivalent to circular section to consider the double constraint function to concrete in steel tube derived from steel tube and outer steel reinforced concrete. Then a new method for the axial ultimate bearing capacity of square steel tube-reinforced concrete column was deduced. The results were in good agreement with the experimental results and the correctness of the theory formulae was proved. Influential effects of some parameters were analyzed and the analysis results showed that the ultimate bearing capacity of square steel tube-reinforced high strength concrete column increased with the increase of the side pressure coefficient. Influence coefficient of intermediate principal stress， the material of tension and compression ratio and the longitudinal reinforcement ratio， while it decreases with the increase of radius-thickness ratio.

Keywords：steel tube-reinforced concrete column；stirrup constraint； strength theory； ultimate bearing capacity

高强钢管混凝土叠合柱是由截面中部的高强钢管混凝土柱和钢管外的钢筋混凝土叠合而成的柱，也可以看成是在钢筋混凝土内置钢管混凝土而成的柱，内截面钢管形式有圆钢管、方钢管和矩形钢管，又可称为核心高强钢骨混凝土组合柱。高强混凝土有强度高、变形小的优点，但其延性差、脆性大，不利于抗震；将其与钢管结合，可以充分发挥二者的性能，同时也具有较好的变形能力、较大的刚度和良好的抗火性能等优点，经济效益良好[1-2]。……