为了研究振动搅拌对混凝土耐久性的影响规律,通过测试分析不同搅拌条件和搅拌参数下混凝土的含气量和强度,分析比较不同振动方式对混凝土含气量的影响机理,并利用电镜照片和汞压法测试孔结构进行微观原理的分析.结果表明,除了目前国内外普遍采用的掺加引气剂的方法外,通过合理的搅拌方式,即混凝土搅拌机的搅拌叶片在强制搅拌物料的同时,也作为振动源对物料施以振动作用的振动搅拌方式,也可以显著提高混凝土的含气量;合适的振动搅拌可以使新拌混凝土含气量普遍达到3.5%左右,又具有较高的强度.微观原理的分析表明,振动搅拌可以促进混凝土中过渡层和水泥水化浆体的显微结构改善,还可以改善混凝土的孔结构分布,从而提高混凝土的强度和耐久性.%In order to determine the influence of vibrating mixing on concrete's durability, influencing mechanism of different vibrating ways on concrete's air content was compared and analyzed by testing and analyzing concrete's air content and concrete strength under different mixing conditions and mixing parameters, and microscopic pore structure was analyzed by using the electronic microscopy and mercury poromesitry. The results showed that besides adding air entraining agent used widely at home and abroad at present, adopting reasonable mixing method could also significantly improve concrete's air content, i.e. compulsively stirs and vibrates. By using the proper vibrating mixing method, the air content of fresh mixed concrete could reach about 3.5 percent in average and the concrete could obtain relatively high strength at the same time. The analysis of microscopic principle show that the vibrating mixing can promote the improvement of the microstructure of the concrete's transition layer and cement's hydration slurry, the pore distribution of concrete, that results in increasing the strength and durability of the concrete.
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