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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 (referred to as steel pipe reinforced PE pipe) asymmetric spiral wound corrugated structure, in order to study the force and deformation of such pipe weak links, through the laying of the pipeline disease changes in the follow-up survey, analysis and analysis The type and characteristics of the type of tube disease, on the site of the pipe to be divided into circumferential and longitudinal hot-melt joints and no hot-melt joints of polyethylene (PE) tensile properties of the test materials, the use of self-made mold shear strength test, and Combined with three-dimensional numerical analysis, the stress characteristics, disease causes and weak links of steel pipe reinforced PE pipe are discussed. The results showed that the main defects of the PE pipe reinforced with steel strip were: bursting (15%), interfacial fracture (9%), circumferential crack (67%) and bulge (9% The tensile strength is 14% less than the axial direction, the elongation at break is 347.7% greater than the axial direction, and the tensile strength of the material without axial hot-melt seams is 20% greater than that of the hot-melt-seamed material. Brittle fracture, hot melt seam tensile strength value of a certain degree of fluctuations; at the foot of the steel strip and two feet at the center of the corresponding PE stress larger and have obvious rules, but the PE material less stress, will not happen before the first shear Cutting damage; pipe structural characteristics related to the disease as the ring crack and bulging bag; PE reinforced PE pipe material is anisotropic, perpendicular to the direction of the strip PE material tensile properties of poor, hot melt joints The weakness is the main factor leading to circumferential cracking of the pipe. The bonding site between the steel strip foot and the inner layer is another weak link, which is the main factor that causes the steel strip and the inner layer to fall off and form the upper and lower bulge.