Experimental Research Of Nano-silica Modified Shrinkage-compensating Concrete Under Erosion

Durability under the erosion of sulphate and chloride is one of the key indicators for measuring concrete material quality. Experiment using shrinkage-compensating concrete with6%swelling agent, nano silicon which has0%,0.6%,1.2%and1.8%and double incorporation of0.6%nano silicon and1.2%steel fibre, erosion under sodium sulfate solution and sodium sulfate mixture with sodium chloride solution. Experiment using "sustain soak method", erode interval age is50d, different composition compensation shrinkage concrete under sodium sulfate solution soak50d,100d,150d,200d,250d,300d, under sodium sulfate mixture with sodium chloride solution soak50d,100d,150d,200d. After test with compressive strength and splitting tensile strength, date deal with "Range Method", Results indicate that:After erosion, different shrinkage-compensating test specimens compressive strength and splitting tensile strength appearing fallen after gross trend with the increase of erosion age. Shrinkage compensating concret with1.2%nano silica, strength reach maximum. However lager content of nano silica will increase cracking sensitivity to concret, after erosion with0.6%nano silica show high performance to1.2%and1.8%. Adding with0.6%nano silica, under erosion with sodium sulfate solution to100d, compressive strength increased by39.94%, to150d splitting tensile strength increased by29.46%; under mixture solution erode150d, compressive and splitting tensile strength increased by28.27%and39.4%. Mix with1.2%fiber and0.6%nano silica to erosion with sodium sulfate solution, the compressive strength and splitting tensile strength reached to64.2MPa and6.31MPa. After erosion with sodium sulfate mixture with sodium chloride solution, the compressive strength and splitting tensile strength reached to62.1MPa and6.21MPa.Due to nano silicon dioxide can reduce permeate of chloride ion, degradation of different groups test specimens of in sodium sulfate mixture with sodium chloride1:1erosion will be lower than independent sodium sulfate erosion. Figure39table13reference86...