纤维表面处理对FRP-水泥砂浆抗弯性能的影响

分别对碳纤维和芳纶纤维进行表面处理，并利用三点弯曲梁试验来研究水泥砂浆外贴该两种纤维片材后的抗弯性能．结果表明：粘贴碳纤维和芳纶纤维片材能极大提高水泥砂浆的抗弯强度和韧性指数，其最大断裂荷载增幅超过150％，破坏模式从脆性的突发性破坏转变为具有一定延性的积累性破坏；经等离子体表面处理后的碳纤维和芳纶纤维，可使CFRP-水泥砂浆和AFRP-水泥砂浆的最大断裂荷载和韧性指数都显著提高，而且构件在受弯过程中是被拉断的，充分发挥了纤维高强的特点．

Influence of Surface Modification of Fibers on the Flexural Properties of FRP-Cement Mortar

The surfaces of carbon fiber sheet and aramid fiber sheet were modified respectively by using of nitric acid, coupling agent and plasma. The sheets were then bonded to cement mortar externally, which called FRP-cement mortar. The flexural properties of FRP-cement mortar were investigated by 3-point bending test. The results show that the flexural properties of cement mortar are improved greatly by bonding carbon fiber or aramid fiber sheets. Their maximum loads increase more than 150%, and fracture modes are changed from brittleness to the accumulation breaking with ductility. The maximum loads and toughness indexes of CFRP-cement mortar and AFRP-cement mortar increased obviously after carbon and aramid fiber sheets were modified by means of plasma. When the specimens are bended, they are tensile fracture, which indicates that the high strength of fibers is fully utilized.