缓粘结剂固化前后预应力筋应力损失及粘结性能  

Stress loss and adhesive properties of retard-bonded PC tendons before and after retard-bonded adhesive cure

作　　者：王占飞[1] 胡正伟[1] 曹少朋 马玥[3] 

机构地区：[1]沈阳建筑大学交通工程学院,辽宁沈阳110168 [2]沈阳建筑大学土木工程学院,辽宁沈阳110168 [3]大连海洋大学应用技术学院,辽宁大连116300

出　　处：《辽宁工程技术大学学报（自然科学版）》2017年第6期619-623,共5页Journal of Liaoning Technical University (Natural Science)

基　　金：辽宁省高等学校杰出青年学者成长计划(LJQ2014060)

摘　　要：为明确缓粘结剂固化前和固化后的缓粘结预应力筋应力损失及粘结性能,分别进行了预应力筋张拉试验和预应力混凝土梁竖向加载试验.在张拉试验中,制作了2个直线布置3根缓粘结预应力筋的预应力梁,分别在缓粘结剂固化前和固化后进行预应力筋的张拉,测试应力损失.在预应力混凝土梁加载试验中,制作了2个同样的预应力梁,分别在缓粘结剂固化前后进行了承载力试验,测试了梁的承载能力和缓粘结剂的粘结性能.试验结果表明:缓粘结剂固化前,粘结性能较弱,张拉时摩擦引起的应力损失较小,适合张拉作业;承载时,梁端预应力筋应力增加近600 MPa,与混凝土没有形成共同工作状态,梁的承载能力和延性较低;缓粘结剂固化后,粘结性能较强,张拉时摩擦引起的损失应力显著,不适合张拉作业;承载时,梁端预应力筋应力增加不到20 MPa,与混凝土具有良好的共同工作状态,梁的承载力及延性有显著提高.To investigate stress loss and adhesive properties of retard-bonded PC tendons before and after retard-bonded adhesive cure, retard-bonded PC tendons＇ tensile experiments and PC beams＇ vertical loading experiments were carried out respectively. In the PC tendons＇ tensile experiments, two PC beams with three straight pre-stressed retard-bonded tendons were tensile and tendon＇s stress loss were measured. In the PC beams＇ loading experiment, two PC beams as described above were made and bending capacity of beam and adhesive properties were measured. The experimental result shows that the tensile friction stress loss is small because of weak adhesive properties before retard-bonded adhesive＇s cure, so it is fit for tensile operation. When it＇s loading, the stress ofpre-stressed tendons＇ ends increase by 600Mpa. Because the concrete and tendons can＇t work together, the bearing capability and ductility are poor. And the tensile friction stress loss is large because of strong adhesive properties after retard-bonded adhesive cure, so it is not fit for tensile operation. When it＇s loading, the stress of pre-stressed tendons＇ ends increase by not more than 20Mpa. Because the concrete and tendons work together well, the bearing capability and ductility is significantly improved.

关 键 词：缓粘结剂 固化程度 预应力筋 应力损失 粘结性能 承载能力 

分 类 号：TU378.2[建筑科学—结构工程]