预制挡板生产工艺质量控制

The Quality Control of Prefabricated Baffle Production Process

成都轨道交通高架区间采用清水混凝土挡板装饰桥面,挡板成品具有尺寸偏差小、钢筋和预埋件定位精度要求高、外观质量要求严的技术特点。挡板的外观质量和清水饰面效果,与模具设计、钢筋笼制作、混凝土原材料选择及配合比、混凝土浇筑成型与养护、成品防护等工艺控制密切相关,通过对挡板预制工艺对比分析,选用高精度模具水平反打成型,气体保护焊制作钢筋笼,配制低坍落度的高性能混凝土,混凝土施工采用风动振捣和振动棒辅助振捣、精收面成型,实施蒸汽养护或自然养护提高早期强度、浸水养护调整色差并做好成品防护;对挡板成品构件的质量缺陷进行系统分析,实施对策具有较强的实践性、指导性,实现了预制挡板构件成品色泽均匀、内实外美的清水饰面效果,为相关产品的生产提供参考。

The elevated section of Chengdu rail transit adopts fair faced concrete baffles to decorate the bridge deck.The finished baffles have the technical characteristics of small dimensional deviation,high positioning accuracy requirements for reinforcement and embedded parts,and strict appearance quality requirements.The appearance quality and finish effect of the baffle are closely related to the mold design,reinforcement cage fabrication,concrete raw material selection and mix ratio,concrete pouring,molding and curing,finished product protection and other process control.Through the comparative analysis on the baffle prefabrication process,high-precision molds are selected for horizontal reverse molding,and the reinforcement cage is fabricated by gas shielded welding to prepare high-performance concrete with low slump.For concrete construction,pneumatic vibration and vibrating rod shall be used for auxiliary vibration and fine finishing.Steam curing or natural curing shall be carried out to improve the early strength.Immersion curing shall be used to adjust the color difference,and finished products shall be protected.The quality defects of finished baffle components are systematically analyzed.The implemented countermeasures have strong practicality and guidance.The finished baffle components have uniform color,solid inside and beautiful outside water finish effect,which provides a reference for the production of related products.