摘要
桁架钢筋混凝土叠合板底板是装配式建筑中应用最广泛的构件,但在生产运输环节普遍存在着开裂问题,而更换预应力筋和增加横向钢筋支架是提高底板抗裂性的有效方法。文章通过理论计算和试验,研究了预制底板开裂的影响因素。结果表明:桁架钢筋混凝土叠合板底板在使用前阶段,会有双向裂缝产生;对60 mm厚预制底板,在脱模起吊阶段应力计算中,采用预应力筋能使x方向混凝土的开裂应力提高149%,增加横向钢筋支架会使y方向混凝土的拉应力减少了21.8%;而附加横向钢筋支架则使桁架钢筋混凝土叠合板预制底板的开裂荷载和极限荷载分别提高了26.4%、31.8%,其对预制底板纵向抗裂性能的提升作用明显。
The precast slab of steel bar truss concrete laminated slab is an widely used component in the prefabricated construction,there are cracks in the production and transportation link,and replacing prestressed steel bars and adding transverse reinforcements are effective methods to improve the carck resistance of the precast slab.Through theoretical calculation analysis and experimental research,the article analyzes the influence of various factors on the cracking of precast slab and studies the cracking mechanism of precast slab in steel bar truss concrete laminated slab.The results show that there will be two-way cracks in the bottom slab of truss reinforced concrete composite slab before use.For 60 mm thick prefabricated floor,during the demoulding and lifting phase,replacing the prestressed tendons can increase the concrete cracking stress in the x direction by 149%,and increasing the transverse reinforcement bracket can reduce the concrete tensile stress in the y direction by 21.8%.Additional transverse reinforcement supports can increase the crack load of precast slabs of truss reinforced concrete laminated slabs by 26.4%and the ultimate load by 31.8%,The additional transverse reinforcement supports significantly improves the crack resistance of the laminate slab.
作者
曹高硕
王示
主红香
王斌
CAO Gaoshuo;WANG Shi;ZHU Hongxiang;WANG Bin(School of Civil Engineering, Shandong Jianzhu University, Jinan 250101, China;Shandong INLARIN Technology Co., Ltd., Jinan 250013, China;Shandong Provincial Communications Planning and Design Institute, Co., Ltd., Jinan, 250031, China)
出处
《山东建筑大学学报》
2020年第5期27-34,共8页
Journal of Shandong Jianzhu University
关键词
装配式建筑
叠合板
预制底板
开裂
静力试验
prefabricated construction
laminated slab
precast slab
cracking
static test
