Hot spring environment effects on the engineering properties of concrete mixtures using recycled green materials

• Main Authors: Jung-Nan Chang, 張榮南
• Other Authors: Her-Yung Wang
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/5m2zxz

博士 === 國立高雄應用科技大學 === 土木工程與防災科技研究所 === 104 === The objective of this study is investigated the effects of sulfate ions, bicarbonate ions, carbonate ions, chloride ion and other harmful chemical substances within hot spring water on the anti-corrosion properties of concrete mixtures using renewable green building materials. Slag, fly ash and liquid crystal waste were used as the replacement for cement, sand, and gravel in six concrete mixture designs were studied. Hot spring waters obtained from Chiaohsi, Chihpen, Sihjhongsi and Chohuo areas were used in the study. Water-cement ratio (W/C) of 0.5 was used in all mixture designs. Test specimens were incubated in the test hot spring waters for 7-day, 28-day, 56-day, 91-day, and 120-day with a constant temperature of 45℃ before testing. Compressive strength, flexural strength, bond strength, shear wave velocity, sulfate resistance, and thermal conductivity properties were evaluated. The results of study indicated that the use of slag, fly ash, and liquid crystal waste materials to replace some percentage of cement, sand, and gravel within the concrete mixture design would increase concrete mechanical properties, such as compressive strength, flexural strength and shear strength. In addition, the use of slag within the concrete mixture would increase shear wave velocity, reduce electrical conductivity, and increase thermal conductivity. However, the increase of slag usage in the concrete mixture would reduce the slump and decrease the work ability of the concrete mixture. Moreover, the use of slag and fly ash to replace some percentage of cement and sand within concrete mixture will not change the slump of the concrete mixture. However, this concrete mixture would increase the sulfate resistance property and reduce the bonding strength between concrete and steel bar. The results of this study also indicated that the use of 25% slag, 20% fly ash, and 40% liquid crystal waste materials for replacements within concrete mixture design showed the best durability behavior in hot spring environment, such as corrosion resistance, thermal conductivity, sulfate resistance, electrical conductivity.