Study on evaluation of air-tight concrete compactness in gas tunnel
The preparation and performance evaluation of air-tight concrete is an important technology in gas tunnel construc-tion.The performance variety rule of C40 concrete under different dosage of air-tight agent was studied firstly.Secondly,multiple indexes including air content(A),air permeability coefficient(K),electric flux(Q)and dynamic elastic modulus(Ed)were used to evaluate compactness of C20,C30 and C40 concrete,in addition,the correlation between air permeability coefficient and other test indexes was explored by grey correlation calculation.The results show that air-tight agent reduced permeability coefficient of con-crete effectively without affecting compressive strength.Furthermore,the correlation degrees of gas content A,Q and Ed are all high-er than 0.67,with the K as master sequence,which indicated that A,Q,Ed and K can reflect the tightness of air-tight concrete.Ad-ditionally,the electric flux of concrete decreases gradually,while the dynamic modulus increases slightly with the extension of age,which proves that the compactness improvement of air-tight concrete affected by air-tight agent is a long-term process,and it is more obvious in preliminary effect.
gas tunnelair-tight concretecompactnessgrey correlation
万方数据
维普
