滨海强腐蚀环境桥梁灌注桩耐腐蚀混凝土的制备

Preparation of Corrosion⁃resistant Concrete for Cast⁃in⁃place Piles of Bridges in Severe Corrosive Coastal Environment

针对滨海强腐蚀环境下石衡沧港(石家庄—衡水—沧州—黄骅港)城际铁路桥梁灌注桩面临的严重腐蚀问题,采用抗侵蚀抑制剂和防腐流变剂分别配制了不同配合比混凝土,并对其工作性能、抗压强度和耐久性能进行了对比分析。结果表明:单掺抗侵蚀抑制剂能够在不严重影响混凝土工作性能和抗压强度的前提下,显著提升混凝土的抗渗性能与抗侵蚀性能;单掺防腐流变剂不仅能够降低拌和物塑性黏度,保证混凝土后期抗压强度稳定增长,而且还能降低混凝土的电通量、氯离子扩散系数和吸水率,提高胶凝材料抗蚀系数。综合分析不同配合比混凝土的性能和经济性,建议采用单掺防腐流变剂制备滨海强腐蚀环境下桥梁灌注桩耐腐蚀混凝土。

In view of the serious corrosion problem of the bridge cast-in-place piles of Shijiazhuang-Hengshui-Cangzhou-Huanghua Port intercity railway under the severe corrosion coastal environment,the concrete with different mix proportions was prepared by using corrosion inhibitors and anti-corrosion rheological agents,and their working performance,compressive strength and durability were compared and analyzed.The results show that the single addition of corrosion inhibitor can significantly improve the impermeability and corrosion resistance of concrete without seriously affecting the working performance and compressive strength of concrete.The single addition of anti-corrosion rheological agent can not only reduce the plastic viscosity of the mixture and ensure the stable growth of the compressive strength of the concrete in the later period,but also can reduce the electrical flux,chloride ion diffusion coefficient and water absorption of the concrete,and improve the corrosion resistance coefficient of the cementitious material.Based on the comprehensive analysis of the performance and economy of concrete with different mix proportions,it is recommended to prepare the corrosion resistant concrete of bridge cast-in-place piles under the severe corrosive environment in the coastal area with a single admixture of anti-corrosion rheological agent.