大管桩混凝土力学性能、抗氯离子渗透性和抗冻性研究

对大管桩混凝土的物理力学性能、抗氯离子渗透性能和抗冻性能进行系统研究。对大管桩混凝土的各项性能指标进行系统的测试和分析,并通过扫描电子显微镜（SEM）和压汞试验的微观测试手段,对大管桩混凝土的硬化水泥石结构的晶体形貌和孔隙结构进行微观分析。此外,通过对国内服役近20年的多座大管桩码头开展广泛的耐久性调查和取样分析,获得在役大管桩耐久性状况的宝贵资料,包括海水中氯离子对大管桩的侵蚀情况和冻融侵蚀环境下大管桩的实际耐久性状况。研究表明：大管桩混凝土具有优异的物理力学性能和耐久性指标,具有高强度、高密度、高弹性模量、低渗透性和高抗冻性的综合性能。

Research on mechanical property,resistance to chloride penetration and freezing-thawing property of concrete of large cylinder pile

A systematic research is carried on the physical and mechanical property,resistance to chloride penetration and freezing-thawing property of concrete of large cylinder piles.Each kind of property index is tested and analyzed,and the microstructure of crystal morphology of hardened cement and the pore distribution of large cylinder pile concrete are analyzed by the scanning electron microscope（SEM） and mercury intrusion method.Besides,the durability condition of piles in service,including the corrosive condition under chloride penetration and freeze thawing environment,is obtained by a comprehensive investigation on the large cylinder piles in a large number of ports served for about 20 years in China.The research results indicate that the concrete of large cylinder pile has excellent mechanical property and durability index,as well as the combination property of high strength,high density,high elastic modulus,low penetrability and high frost resistance.