钢筋混凝土框架节点加固试验及理论分析-结构工程专业论文.docxVIP

钢筋混凝土框架节点加固试验及理论分析研究(摘要) 钢筋混凝土框架节点加固试验及理论分析研究 (摘要) 为研究钢筋混凝土框架节点区梁端加固前后的性能，共进行了6个梁柱中节 点模型试件的试验研究。以实际结构构件加固时的状况为依据，本次试验分成两 个阶段。在第一阶段试验中，未加固的试件在低周反复荷载作用下使梁纵筋屈服。 屈服后的试件分别采用加大截面法和粘钢板加固，其中加大截面法加固的试件采 用不同的锚固措施。加固后的试件进入第二阶段试验，即在低周反复荷载作用下 直至破坏。试验中详细地考察了加固前后粱端荷载一位移关系、裂缝和破坏方式、 钢筋或钢板的应变变化等内容。本次试验较一般加固试验更符合实际加固情况之 处在于试件是在受损情况下加固，考虑了加固前试件的损坏给加固带来的影响。 在对试验结果的整理分析后，本文对比研究了加固前后以及用不同加固方法 加固的试件的开裂荷载、屈服荷载和极限承载力、梁端荷载一转角滞回曲线及其 包络线特征、延性和耗能性能。加固后试件破坏同样发生在粱端，屈月艮荷载比加 固前提高12．j％～17．2％，与粘钢加固相比，加大截面法加固的试件承载力提高 幅度较大；加固后试件的延性和耗能性能比加固前有很大的改善，其中以粘钢加 固的试件提高最为明显。 在试验研究的基础上，综合已有的研究成果，本文从理论上分析了加固后梁 端的正截面抗弯承载力、斜截面抗剪承载力、节点的抗剪承载力、以及加大截面 法新旧混凝土之间的界面剪应力、粘钢加固法钢板与混凝土之间的界面剪应力、 新加部分在节点区梁端的锚固等，理论分析的结果与试验结果的吻合较好。同时， 还研究了节点区粱端加固的影响因素，以使加固设计和研究更具有针对性。 在以上研究的基础上，本文针对钢筋混凝土框架结构节点区梁端加固提出了 设计和施工建议，以供工程技术人员参考。 关键词：钢筋混凝土框架节点；低周反复荷载：粘钢加固；加大截面法加固；荷 载一位移滞回曲线 Research Research of Strengthening on Reinforced Concrete Frame Beam—column Joints (AbstracO Six isolated and simplified reinforced concrete(Rc)beam—column joint specimens were tested in order tO study the behavior of the RC frames’beam end zones before and after strengthening．’the specimens were subjected to controlled deterioration under cyclic loading first until yielding of the reinforcement．Then，they were strengthened with RC jacketing and bonding steel plates respectively．The investigated test parameter of the specimens strengthened by RC jacketing were connection types between the new reinforced bars and the column．Eventually，the rehabilitated specimens were retested under low cyclic loading．The loads and displacements of the beam end as well as the steel or plate strain were measured in detail；and furthermore，crack patterns and failure model of the specimens were also observed during the test． Comparison including the cracking，yielding and ultimate loads of the beam， load—displacement CHIVe，envelop curve，the ductility and energy—dissipation capacity were made between the response of the specimens before and after strengthening．Test results indicated that the yie