据微信公众号"国家铁路局"消息，11月14日，国家铁路局发布通报称，针对近日媒体关注的银巴铁路桥梁用橡胶材料"以次充好"问题，兰州铁路监管局高度 重视，立即成立调查组，赶赴现场开展调查核实。 日前，新华社旗下《经济参考报》调查发现，中国铁建旗下中铁十六局在施工过程中，使用的一种桥梁用橡胶材料疑似存在质量问题。记者现场随机抽取的 多处已铺设三元乙丙橡胶板能轻易被割开、扯断。送检结果显示其拉伸强度仅为1.78MPa，仅为标准（"≥12MPa"）的15%，主要成分为性能较差的异戊二烯 橡胶，而非合同要求的三元乙丙橡胶，且部分产品无厂家标识，涉嫌以次充好。 据了解，三元乙丙橡胶板铺设在铁路桥两侧钢横梁上，能避免混凝土电缆槽和钢横梁两个刚性结构之间的直接接触，使受力均匀，起到缓冲、防水和延长桥 体使用寿命的作用。 | 序号 | 项目 | | 单位 技术要求 试验方法 | | | --- | --- | --- | --- | --- | | 1 | 邵A硬度 | 度 | રેરેન્દ | GB/T 531.1 | | 2 | 拉伸强度 | MPa | ≥12 | GB/T528 | | 3 | 拉断伸长率 | 0/0 ...

Core Viewpoint - Recent investigations revealed potential quality issues with rubber materials used in the construction of the Yinba Railway, specifically concerning the inferior quality of ethylene propylene diene monomer (EPDM) rubber sheets, which could pose safety risks and affect the longevity of bridge structures [1][6][18]. Group 1: Quality Issues - Investigative reports indicated that the EPDM rubber sheets could be easily cut and torn, with laboratory tests showing a tensile strength of only 1.78 MPa, which is merely 15% of the required standard of ≥12 MPa [6][9][18]. - The materials tested were found to be primarily made of isoprene rubber rather than the specified EPDM, raising concerns about their durability and performance under harsh conditions [9][18]. - The presence of rough edges and irregularities in the rubber sheets suggested that they may not meet the quality standards expected for EPDM products [9][18]. Group 2: Regulatory Response - The National Railway Administration responded to media reports by forming an investigation team to verify the claims regarding the substandard rubber materials used in the railway project [1][18]. - The project manager from China Railway 16th Bureau expressed a lack of understanding regarding the material properties and stated that they relied solely on inspection reports to accept the materials [10][15][18]. Group 3: Financial Impact - Following the news of the quality issues, shares of China Railway Construction Corporation (601186.SH) experienced a slight decline, closing at 7.97 yuan, with a year-to-date drop exceeding 10%, resulting in a total market capitalization of 108.2 billion yuan [4].

Core Viewpoint - Recent investigations revealed potential quality issues with rubber materials used in the construction of the Yinba Railway, specifically concerning the EPDM rubber sheets supplied by China Railway Construction Corporation's subsidiary, China Railway 16th Bureau Group [2][5][17]. Group 1: Quality Issues - The EPDM rubber sheets were found to be easily cut and torn, with testing showing that their tensile strength was only 1.78 MPa, which is 15% of the required standard of ≥12 MPa [5][8][17]. - The material analysis indicated that the rubber was primarily isoprene rubber rather than the specified EPDM, which has inferior weather resistance and a shorter lifespan [8][17]. - The presence of rough edges and "fuzz" on the rubber sheets suggested that they were not manufactured to the expected quality standards [8][17]. Group 2: Regulatory Response - The National Railway Administration responded to media reports by forming an investigation team to verify the quality issues raised regarding the rubber materials used in the Yinba Railway [2][5]. - The project manager from China Railway 16th Bureau Group acknowledged a lack of understanding regarding the material properties and stated that they relied solely on inspection reports for quality assurance [10][15]. Group 3: Procurement and Compliance - The project had previously issued a procurement announcement for approximately 25,000 EPDM rubber pads, with 9,000 already delivered in three batches, all of which were reported as compliant based on inspection results [11][14]. - There is a discrepancy between the inspection results, with some reports indicating compliance while others reveal significant deficiencies, raising concerns about the quality control processes [15][17]. - The procurement announcement explicitly prohibited the use of recycled rubber in the EPDM sheets, yet the materials in question appeared to be substandard [17].

Core Viewpoint - Recent investigations revealed potential quality issues with rubber materials used in the construction of the Yinba Railway, specifically concerning the EPDM rubber sheets, which may compromise bridge safety and longevity [1][6][18]. Group 1: Quality Issues - The rubber sheets tested were found to be easily cut and torn, with a tensile strength of only 1.78 MPa, which is just 15% of the required standard of ≥12 MPa [6][8][18]. - The material analysis indicated that the rubber was primarily isoprene rubber rather than the specified EPDM, which has inferior weather resistance and durability [8][18]. - The presence of rough edges and irregular particles in the rubber sheets suggests that they may not meet the quality standards expected for EPDM products [8][18]. Group 2: Regulatory Response - The National Railway Administration has taken the issue seriously, forming an investigation team to verify the claims regarding the substandard rubber materials [1][6]. - The project manager from China Railway 16th Bureau expressed a lack of understanding regarding the material properties and relied solely on inspection reports for quality assurance [9][16]. Group 3: Financial Impact - Following the news, shares of China Railway Construction Corporation (601186.SH) experienced a slight decline, closing at 7.97 yuan, with a year-to-date drop exceeding 10%, resulting in a total market capitalization of 108.2 billion yuan [4].