钢带增强聚乙烯螺旋波纹管薄弱环节试验  

Experiment on Weak Link of Steel Reinforced Polyethylene Spiral Corrugated Pipe

作　　者：颜春[1,2] 凌天清[1] 欧冬 

机构地区：[1]重庆交通大学土木工程学院,重庆400073 [2]广西交通科学研究院,广西南宁530007

出　　处：《中国公路学报》2016年第11期33-41,共9页China Journal of Highway and Transport

基　　金："十二五"国家科技支撑计划项目(2015BAK09B01)

摘　　要：钢带增强聚乙烯螺旋波纹管(简称钢带增强PE管)为非对称螺旋缠绕波纹结构,为了研究该类管材受力及变形的薄弱环节,通过对已铺设管道病害变化的跟踪调查,总结分析该类管病害形式及特征,对现场管材分取环向及纵向有热熔接缝及无热熔接缝部位进行聚乙烯(PE)材料的拉伸性能试验,采用自制模具进行抗剪强度试验,并结合三维数值分析对钢带增强PE管的受力特点、病害原因、薄弱环节进行探讨。结果表明:钢带增强PE管的病害主要有顶破(15%)、接口断裂(9%)、环向裂缝(67%)及鼓包(9%);环向无热熔接缝PE材料的拉伸强度比轴向小14%,断裂伸长率比轴向大347.7%,轴向无热熔接缝材料的抗拉强度要比有热熔接缝材料大20%;材料在热熔接缝处易产生脆性断裂,热熔接缝的抗拉强度值有一定的波动;钢带脚处及两脚中心处对应的PE应力较大且有明显的规律,但PE材料受力较小,不会先发生剪切破坏;与管材结构特性有关的病害为环向裂缝及鼓包;钢带增强PE管的PE材料是各向异性的,垂直于钢带方向的PE材料抗拉性能较差,热熔接缝处是薄弱环节,是造成管道环向开裂的主要因素;钢带脚处与内层黏合部位是另一个薄弱环节,是造成钢带与内层脱落形成上下鼓包的主要因素。Steel reinforced polyethylene spiral corrugated pipe has an asymmetric spiral corrugated structure. In order to investigate the stress and deformation of the pipe＇s weak links, the types and the features of pipe failure were summarized and analyzed through the tracking investigation on disease change of the buried pipe. Tensile test for polyethylene （PE） materials and shear strength test which adopted home-made mould were performed on on-site pipes with or without hot melt seams in circumferential and longitudinal directions. The mechanical characteristics, disease reasons, weaknesses of the steel reinforced polyethylene spiral corrugated pipe were discussed combined with three-dimensional numerical analysis. The results show that steel PE pipe diseases mainly contain bursting （15%）, interface cracks （9%）, circumferential cracks （67%）, and top and bottom swelling （90%）. The PE material without circumferential hot melt seams is 14% smaller than the one without the axial seams in terms of tensile strength and 347.7% bigger than the material without axial seams in terms of elongation at break. The tensile strength of material without axial hot melt seam is 20% larger than that of material with hot melt seam. The brittle fracture is produced at the hot melt seam of the material, and there are some fluctuations in the tensile strength value for the hot melt seam. The stresses corresponding to steel feet and the center of steel feet are larger, and show an obvious rule. But the PE material is less stressed, where shear failure does not occur at first. The pipe diseases related to the characteristics of the structure are circumferential cracks and top and bottom swelling. The PE material is anisotropic, the tensile strength of it is poor in the vertical direction of the strip, and the hot-melt seam is the weak link, which is the main cause of circumferential cracks of the pipe; the adhesive area between feet of steel belts and inner side of the PE is the other weak link, which is the main cause in

关 键 词：道路工程 钢带增强聚乙烯螺旋波纹管 拉伸试验 薄弱环节 剪切试验 病害调查 

分 类 号：U417[交通运输工程—道路与铁道工程]