نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشکده عمران، دانشگاه خواجه نصیر الدین طوسی، تهران، ایران
2 دانشکده مهندسی عمران، دانشگاه صنعتی خواجه نصیرالدین طوسی، تهران، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Efforts to reduce the weight of concrete have led to extensive research on lightweight concrete. Reducing the weight of concrete may result in reducing the weight of structures and consequently reducing the forces acting on them. In this study, the effects of two lightweight aggregates, namely LECA and Scoria, on the properties of self-compacting concrete in fresh and hardened phases, as well as its durability in sulfuric acid environment, were investigated. Fresh concrete tests included slump flow, T50 slump flow, L-box, U-box, J-ring, and specific weight tests, while compressive strength tests were conducted in normal and acidic environments, and weight loss in acidic conditions for hardened samples was examined. The results showed that three significant factors affecting concrete performance are the specific weight, appearance, and water absorption percentage of the aggregates. By replacing LECA and Scoria aggregates with the same volume in lightweight concrete, Scoria lightweight concrete exhibited approximately 60% higher strength. The highest reduction in compressive strength of samples placed in acidic environment occurs for LECA lightweight self-compacting concrete between ages 1 to 7 days at about 27%, and for Scoria lightweight self-compacting concrete between ages 7 to 28 days at about 25%, indicating that the greatest impact of acidic environment on strength reduction is observed for LECA lightweight self-compacting concrete up to 7 days and for Scoria lightweight self-compacting concrete from 7 to 28 days. The highest weight loss for samples placed in acidic environment for both types of concrete occurs between ages 1 to 14 days at approximately 93%, with only about 7% weight loss between ages 14 to 28 days. It is worth noting that compared to the initial weight, the samples experience a very slight weight reduction of about 1% to 2%.
کلیدواژهها [English]
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