Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Engineering
Establishment Of A Numerical Model For Sulfate Attacked Concrete Considering Multi-Factors, Shanshan Qin, Dujian Zou, Jun Jiang, Tiejun Liu
Establishment Of A Numerical Model For Sulfate Attacked Concrete Considering Multi-Factors, Shanshan Qin, Dujian Zou, Jun Jiang, Tiejun Liu
International Conference on Durability of Concrete Structures
Sulfate attack is one of the major durability problems of concrete structures, which is manifested by expansive cracks and deterioration of cement paste. In this study, a numerical model is proposed to predict the process of ionic diffusion into concrete under external sulfate attack. The chemical reaction and diffusion processes are considered in this model. Furthermore, the influence of calcium leaching, chemical activity of multi-ions, temperature and changes in porosity are also taken into account. The initial porosity and tortuosity are assumed to be homogeneous in concrete, and the chemical potential gradient is regarded as the driving force for ions …
Using Long-Term Outdoor Exposure Data To Benchmark Accelerated Durability Test Methods, R. Hooton
Using Long-Term Outdoor Exposure Data To Benchmark Accelerated Durability Test Methods, R. Hooton
International Conference on Durability of Concrete Structures
Many performance-based durability test methods adopted in various national and international standards were developed decades ago based on short-term evaluations. Most durability tests use various methods to accelerate reactions in order to obtain results in a reasonably short period of time. Then pass/fail criteria are set for these tests in standard specifications. However, the acceleration techniques used maybe overly severe, and preclude the use of concrete materials and mix designs that perform perfectly well in the field. The inclusion of long-term field tests or outdoor exposure tests can be used to verify the appropriateness of both the test methods and …
Performance Of High-Volume Fly Ash Self-Compacting Concrete Exposed To External Sulfate Attack, Tareq S. Al-Attar Dr., A. A. Taha
Performance Of High-Volume Fly Ash Self-Compacting Concrete Exposed To External Sulfate Attack, Tareq S. Al-Attar Dr., A. A. Taha
International Conference on Durability of Concrete Structures
The high-volume fly ash concrete, HVFAC, could be defined as any concrete mix having fly ash content larger than 50 percent of the total cementitious materials content. Due to the availability of fly ash in large quantities globally with low cost, HVFAC could be considered as a solution for the environmental impact of Portland cements. In this study the durability of two high-volume fly ash self-compacting concrete, HVFASCC, mixes exposed to the effects of two sulfate aggressive solutions was investigated. The fly ash, class F, contents for these mixes were 50 and 60 percent by weight of Portland cement. The …
Effect Of Nanosilica On The Sulfate Attack Resistivity Of Cement Mortar, Pengkun Hou, Zh Guo, Q Yu, N Xie, X Cheng, Sp Shah
Effect Of Nanosilica On The Sulfate Attack Resistivity Of Cement Mortar, Pengkun Hou, Zh Guo, Q Yu, N Xie, X Cheng, Sp Shah
International Conference on Durability of Concrete Structures
The effect of nanosilica on the sulfate attack resistivity of cement mortar was investigated through study on the mechanical property evolution and the length change of the cement mortar under 5 wt.% sodium sulfate for 6 months. Meanwhile, the effects were compared with those of fly ash-replacement mortar. Results showed that by taking the advantages of nanosilica and fly ash in improving the property of cement mortar at early and later ages, the sulfate attack resistance of cement mortar can be enhanced in mechanical property increase and expansion reduction. Further, it implies that a combination of both pozzolans could enhance …