体外预应力FRP筋加固混凝土单向板受弯性能及承载力计算方法

Flexural Property and Calculation Method of One-way Reinforced Concrete Slabs Externally Prestressed with Unbonded FRP Tendons

以FRP筋张拉应力和加固量为试验参数,制作了6块混凝土单向板,包括1块对比板和5块体外预应力玻璃纤维增强复合材料(GFRP)筋加固混凝土单向板,分析了体外预应力筋对混凝土单向板受力性能的影响.结果表明,体外预应力FRP筋对混凝土单向板开裂荷载、屈服荷载和极限荷载均有明显的提高.结合本文和已有文献的试验结果,分析了张拉控制应力、FRP筋加固量和加固长度、FRP筋有效高度对混凝土受弯构件性能的影响,提出了体外预应力FRP筋加固混凝土受弯构件承载力计算方法.该方法适用于体外预应力FRP筋加固混凝土梁和单向板受弯构件承载力的计算.

Taken the quantity and tension control stress of FRP tendons as test parameters, six one- way reinforced concrete slabs, including one reinforced concrete slab for comparison and five reinforced concrete slabs externally prestressed with unbonded glass fiber reinforced polymer （GFRP） tendons, were tested to analyze the effect of externally prestressed tendons on the property of reinforced concrete slabs. The experimental results show that externally prestressed unbonded tendons with glass fiber reinforced polymer （ GFRP ） improve the flexural capacity, such as the cracking load,yielding load and ultimate load of one-way reinforced concrete slabs obviously.Combined the test results in this paper with the results in the existing literature, the effect of quantity, tension control stress, strengthening length and the effective height of FRP tendons on the property of reinforced concrete slab were analyzed.A calculation method suitable for the load bearing capacity of reinforced concrete beam and one-way slab prestressed with unbonded FRP tendons was proposed.