In this study the computerized tomography (CT) was first used to quantitatively analyze the failure of acrylate spray-applied waterproof membrane in the groundwater environment. The results of the CT tests show that i...In this study the computerized tomography (CT) was first used to quantitatively analyze the failure of acrylate spray-applied waterproof membrane in the groundwater environment. The results of the CT tests show that it is feasible to use the CT to quantitatively analyze the failure of the waterproof membrane and the CT method has the advantages of speediness and accuracy that can eliminate the fussy operation process in routine tests. The main conclusions summarized from the study are as follows. First, there are two combined-indexes that can be used to decide the failure of the spray-on waterproof layer: one is that the reduced percentage of the CT number of the spray-on waterproof layer is less than 40.0% and the other is that the variance of the CT number decreases first and then increases. Second, the applicability for the spray-on waterproof layer in the groundwater environment is the SO 24-concentration ≤ 1%, the Cl-concentration ≤ 7.5% and the pH value ≤ 12.0 of the groundwater, respectively.展开更多
Based on the Wuhan Yangtse River Tunnel Project, the low-penetration fiber concrete used in the protecting layer of Wuhan Yangtse River Tunnel tube has been studied in this paper. With the effect of silica fume, slag ...Based on the Wuhan Yangtse River Tunnel Project, the low-penetration fiber concrete used in the protecting layer of Wuhan Yangtse River Tunnel tube has been studied in this paper. With the effect of silica fume, slag and polypropylene fiber on the anti-penetration of tunnel concrete by means of NEL test, XRD and SEM, some conclusions has been drawn. The affection on the anti-penetration capability of the four factors is capacity of silica fume>portion of short and long fiber> fiber VOL Portion>length of Fiber. Fiber capacity of 0.15% is still not good enough for the anti-penetration capability of concrete. While that of 0.5% has exceed the maximum, and the fiber tends to assemble together. Silica fume may greatly enhance the anti-penetration capability of concrete, while the relationship between them is not direct proportion. The average of chloric ion pervasion coefficient with 8% capacity of silica fume is the lowest. Slag may reacted with other component to generate lots of C-A-H. When reacted with free chloride ion, C-A-H may form friedel salt which may also enhance the Anti-penetration capability of concrete.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 50678151)
文摘In this study the computerized tomography (CT) was first used to quantitatively analyze the failure of acrylate spray-applied waterproof membrane in the groundwater environment. The results of the CT tests show that it is feasible to use the CT to quantitatively analyze the failure of the waterproof membrane and the CT method has the advantages of speediness and accuracy that can eliminate the fussy operation process in routine tests. The main conclusions summarized from the study are as follows. First, there are two combined-indexes that can be used to decide the failure of the spray-on waterproof layer: one is that the reduced percentage of the CT number of the spray-on waterproof layer is less than 40.0% and the other is that the variance of the CT number decreases first and then increases. Second, the applicability for the spray-on waterproof layer in the groundwater environment is the SO 24-concentration ≤ 1%, the Cl-concentration ≤ 7.5% and the pH value ≤ 12.0 of the groundwater, respectively.
文摘Based on the Wuhan Yangtse River Tunnel Project, the low-penetration fiber concrete used in the protecting layer of Wuhan Yangtse River Tunnel tube has been studied in this paper. With the effect of silica fume, slag and polypropylene fiber on the anti-penetration of tunnel concrete by means of NEL test, XRD and SEM, some conclusions has been drawn. The affection on the anti-penetration capability of the four factors is capacity of silica fume>portion of short and long fiber> fiber VOL Portion>length of Fiber. Fiber capacity of 0.15% is still not good enough for the anti-penetration capability of concrete. While that of 0.5% has exceed the maximum, and the fiber tends to assemble together. Silica fume may greatly enhance the anti-penetration capability of concrete, while the relationship between them is not direct proportion. The average of chloric ion pervasion coefficient with 8% capacity of silica fume is the lowest. Slag may reacted with other component to generate lots of C-A-H. When reacted with free chloride ion, C-A-H may form friedel salt which may also enhance the Anti-penetration capability of concrete.
