【摘要】 对4根钢管微膨胀混凝土短柱和3根普通钢管混凝土短柱先后进行了收缩/膨胀性能和推出试验的研究。试验结果表明,由于膨胀剂的掺入,核心混凝土在钢管的限制作用下产生了一定的预压应力,膨胀剂掺量和水灰比对钢管微膨胀混凝土的限制膨胀性能有重要影响,核心混凝土中的预压应力能有效提高钢管混凝土短柱的界面粘结强度。根据推出试验结果,分析了粘结破坏的发展过程;给出了试件的荷载—滑移曲线;最后建议了一种新的改善组合结构界面粘结性能的方法。更多还原

【Abstract】 The shrinkage/expansion behaviors and bond carrying capacities of 4 short,micro-expansive concrete-filled steel tube columns and 3 short,conventional concrete-filled steel tube columns were experimentally investigated.The results indicate that pre-stress is produced in the core concrete under the confined by the steel tube.Both expansive agent and water cement ratio have important influence on expansive behaviors of micro-expansive concrete-filled steel tube specimens.The pre-stress in concrete core can improve the bond strength effectively.Based on the push-out test results,the developing process of bond breakage was analyzed and the load-slip curves of each specimen were obtained.Finally,a new method to improve the bond strength of composite structures was recommended.更多还原