纤维编织网增强细粒混凝土加固RC受弯构件的正截面承载性能研究

采用纤维编织网增强混凝土(TRC)这种新型材料对结构进行修补加固不仅可以改善结构的性能,而且可以几乎不增加结构的截面尺寸。但由于纤维材料的脆性特征,在达到其极限抗拉强度时会发生拉断破坏,这对于结构来说是不安全的。为此,取单筋矩形梁研究,针对不同的纤维编织网的用量给出增强梁的两种界限破坏状态,并给出这两种状态分别对应的配网率与钢筋配筋率之间的关系。然后,基于平截面假定,给出TRC增强受弯构件在三种破坏形态下正截面极限承载能力的计算方法,包括一次受力和二次受力的情况。最后,结合试验数据说明第一种破坏模式的不利性,且采用该方法得到的承载力计算值与试验结果吻合得较好。

Investigation on the bearing capacity of the normal section of RC flexural component strengthened with textile-reinforced concrete

The structural performance can be enhanced without increasing the section size of the component when the new composite of textile reinforced concrete(TRC) is applied to strengthen and retrofit existing structures.However,due to the brittle feature of fiber materials,tensile failure would occur if the ultimate tensile strength of textile is reached,which is unsafe for structures.Therefore,for a single rectangular beam,two types of limit failure states of beams strengthened with TRC are presented for different amounts of textile,and for each state,the relationship between the textile ratio and the steel reinforcement ratio is derived.Based on the plane section assumption,calculation methods for the ultimate bearing capacity of the normal section of the component strengthened with TRC in three types of failure mode are also presented,including first load and secondary load.The experimental results show that the first failure mode is unfavorable to the component and the calculated values of ultimate bearing capacity agree well with the experimental values.