原材料微观检测技术在跨海大桥混凝土质量控制中的应用

Application of Raw Material Microcosmic Detection Technology in Concrete Quality Control of Cross-sea Bridge

目前,跨海大桥混凝土原材料的检测仍停留在强度、活性指数、减水率等宏观性能指标上,尚无专门的技术标准来规范原材料的物相组成、颗粒形貌、有效含量、分子结构等微观原始特征方面的要求,从而无法做到从源头去控制原材料的质量与性能。现采用X射线衍射分析、扫描电镜分析、凝胶色谱分析等微观测试手段,建立了混凝土原材料成套检测方法,并应用此方法对某跨海大桥所使用的水泥、粉煤灰、磨细矿粉、外加剂等材料进行全程监控。通过对比不同批次原材料的微观特征参数,并结合现场混凝土强度的测试结果,最终实现原材料质量的可溯。研究结果表明,微观检测方法的引入有效地提升了跨海大桥混凝土原材料的管控水平,保证了混凝土强度等关键指标的均匀性。

At present,the detection of concrete raw material of cross-sea bridge is still at the macro-property indexes of strength,active index and water-reducing rate.There is no special technical standard to standardize the microcosmic primitive characters of phase composition,particle morphology,efficient content and molecular structure of raw materials so as hard to control the quality and properties of raw materials at sources.At present,the microcosmic detection means of X-ray diffraction analysis,scanning electron microscope analysis and gel chromatographic analysis are used to establish a complete set of detection method for concrete raw material.And this method is applied to carry out a whole-process monitor for the materials of cement,fly ash,fine mineral powder and admixture.Through the comparison of the microscopic feature parameters of different raw materials and combined with the testing results of in-site concrete strength,the traceability of raw material quality is realized finally.The study result shows that the introduction of microcosmic detection method can efficiently improve the management and control level of concrete raw materials for cross-sea bridges and guarantee the uniformity of the key indexes of concrete strength and etc.