西江特大桥大直径桩基混凝土配合比设计验证与应用

江门至肇庆高速公路横跨喀斯特地区,桩基施工技术复杂,对桩基混凝土质量要求较高。以西江特大桥混凝土配合比设计为研究背景,对承包人申报的大直径桩基配合比标准试验进行了平行验证,其混凝土强度、耐久性、和易性等性能指标与申报的试验指标有差异,分析了承包人试验室技术人员出现这些差异的原因,并就原配比提出优化意见。重新试验后,使各项指标与申报资料相符,该混凝土配合比在施工应用后,符合工程施工要求,桩基完整性检测结果均为I类桩。

Mix Design Verification Technology and Application of Concrete for Large Diameter Piles of Xijiang Bridge

As Jiangmen-Zhaoqing Expressway goes across the Karst area, with complicated pile foundation construction technology and high quality requirements for concrete, based on the concrete mix design for Xijiang Bridge, parallel verification has been carried out for the mix design standard test of large diameter piles submitted by Contractors, while differences have been found in the concrete strength, durability, workability and other per- formance indicators, causes for such differences by Contractor laboratory technicians have been analyzed and sug- gestions of optimization on the mix design have been proposed, and after re - testing, every indicator can conform with the submitted, which can finally meet the construction requirements when applied in works with class I pile reached by pile integrity detection.