【摘要】 研究了水胶比、防水剂品种、粉煤灰掺量和超量取代系数以及机制砂的石粉含量对隧道二次衬砌混凝土工作性、强度和抗渗性的影响。结果表明:采用防水剂不及降低水胶比对混凝土的抗渗性改善显著,机制砂中的石粉含量增至12%~14%有利于混凝土工作性、强度和抗渗性的提高。据此,提出了两种二衬防水混凝土的配制方法:一是采用II级粉煤灰超量取代与高效减水剂双掺技术降低水胶比,从而平衡二衬防水混凝土的低强、大流态和抗渗性的矛盾;另一种是采用高石粉含量机制砂配制二衬防水混凝土,以节约水泥用量并提高抗渗性。更多还原

【Abstract】 The effects of water-binder ratio;types of water-proofing agent;fly ash replacement;the exceeding coefficient of fly ash and microfines content of manufactured sand on workability,strength and impermeability of tunnel secondary linnning concrete were studied by expecimenting.The results show that water-proofing agent does not improve the impermeability of concrete as significantly as low water-binder ratio does,the increment of stone powder content to 12 to 14%is beneficial to improve workability,strength and impermeability of concrete.Hereby,two mix proportion designs of secondary linning water-proofing concrete are proposed.The relationship of low intense,super-flowing and impermeability of secondary linnning water-proofing concrete by reducing water-binder ratio with superplasticizer and exceeding replacement of secondary grade fly ash,which is the first one.The amount of cement is reduced and the impermeability of concrete is improved by utilizing manufactured sand with high microfines content to produce secondary linning water-proofing concrete,which is the second one.更多还原