带砂浆包覆层CFRP筋高温后力学性能研究

Study on high temperature performance of CFRP bars covered with cladding layer

分别采用普通砂浆和纤维聚合物砂浆两种包覆层材料,对36根带砂浆包覆层CFRP筋试件进行了高温后力学性能的试验。待试件筋材表面温度达到400℃后持时1 h或2 h,取出筋材测试其高温后的抗拉强度。试验结果表明,在砂浆包覆层保持完好未爆裂的情况下,包覆层为CFRP筋提供了较好的隔氧环境,CFRP筋在长时间高温持时作用后具有较高的残余强度。

The mechanical properties of 36 CFRP bars covered with common mortar and fiber polymer mortar cladding layers were tested after elevated temperature. When the surface temperature of CFRP bars reached to 400 ,the temperature was maintained for a heating period of lh or 2h,then the CFRP bars were taken out to test their residual strength after high temperatures. The results show that when the mortar cladding layer remained intact and not bursting the cladding layer can provide a relatively good oxygen isolation for CFRP bars and the residual strength of CFRP bars maintaines at a relatively high level.