夹心保温墙体GFRP连接件轴向性能研究

夹心保温墙体是一种兼具承重、围护、保温功能的预制构件。墙体包括内外叶钢筋混凝土板和中间保温层。连接件垂直穿过保温层，将外叶板的荷载传递至内叶板，其力学性能对保证墙体安全性至关重要。传统连接件在保温层超厚条件下存在刚度不足，承载力受施工质量影响大等问题。为此，设计了新型GFRP工字型连接件，提出端部插入锚固钢筋的新型锚固形式，并进行了试验研究和有限元分析。试验研究表明:连接件拉拔和受压破坏模式为混凝土冲切劈裂锚固破坏，其承载力分别为25.6 kN和36.8 kN。有限元分析得到了连接件端部混凝土受力状态和破坏模式，发现锚固钢筋对混凝土破坏模式起重要作用。基于试验和有限元分析结果，提出冲切破坏面确定方法和承载力计算公式，为连接件设计提供参考。

AXIAL PERFORMANCES OF A GFRP CONNECTOR FOR SANDWICH INSULATION WALL PANELS

Sandwich insulation wall panel(SIWP) is a type of precast components with load-bearing, enclosure and insulation functions. The SIWP is composed of inner and the outer reinforced concrete slabs and middle insulation layer. The connectors penetrate the insulation layer and transfer loads from the outer layer to the inner layer. The performance of the connectors is crucial to maintain the safety of the panels. However, the conventional connectors may not have adequate stiffness if the insulation layer is too thick, and the quality control is difficult for the installation. In this study, a GFRP I-shaped connector was developed, the associated anchorage method featured with the anchorage rebar penetrating the holes at connector ends was proposed, and tests and finite element analyses were carried out. The experimental results find that the failure modes of the connector are concrete punching and splitting failure. The pull-out and compression strength of the connector are 25.6 kN and36.8 kN, respectively. The finite element analyses suggest that the anchorage rebar is important for the failure mode. Based on the test and analysis results, methods to determine the punching failure surface and estimate the load bearing capacity are proposed, which are expected to provide references for engineering design practices.