冻融-氯盐耦合作用下整体防水混凝土耐久性试验研究

Properties of integral waterproofing concrete under the coupling effect of freeze-thaw and chloride

在研究冬季北方除冰盐地区或近海环境,考虑冻融损伤和氯盐侵蚀耦合作用下整体防水混凝土的耐久性能。将不同水灰比和硅烷乳液掺量的整体防水混凝土试件置于3%Na Cl溶液中,进行加速冻融循环试验,测定不同盐冻循环次数下的相对动弹性模量、质量损失和渗透性,以综合评价整体防水混凝土耐久性。试验结果表明,在冻融-氯盐耦合作用下,整体防水混凝土冻融损伤和质量损失均随着硅烷掺量和冻融循环次数的增加而增加,降低水灰比可以有效提高整体防水混凝土抗冻性。但是,在相同冻融循环次数下,整体防水混凝土仍较普通混凝土具有更好的抗渗透性,并且抗渗透性随着硅烷乳液掺量的增加而提高。

It aims to investigate the durability of concrete exposed to the coupling effects of freeze-thaw and chloride penetration under deicing salt and marine environment.Various integral waterproofing concrete specimens with different W/C and silane emulsion were prepared first.The prepared specimens were put into 3% Na Cl solution,and then the accelerated freeze-thaw cycles experiment was carried out.The relative dynamic modulus,mass loss and permeability of specimens were measured,which aims to evaluate the durability of integral waterproofing concrete.The results show the freeze-thaw damage and mass loss increase with the increase of freeze-thaw cycles and added silane emulsion,and reducing the W/C is an effective way to improve the freeze-thaw resistance of integral waterproofing concrete.However,comparing with the permeability resistance of fresh concrete and integral waterproofing concrete,integral waterproofing concrete possesses better permeability resistance than fresh concrete,and the permeability resistance increases with the addition of silane emulsion increasing.