نوع مقاله : مقاله پژوهشی
1 گروه مهندسی عمران، دانشکده مهندسی شهید نیکبخت، دانشگاه سیستان وبلوچستان، زاهدان، ایران
2 دانشجوی کارشناسی ارشد، گروه مهندسی عمران، دانشکده مهندسی شهید نیکبخت، دانشگاه سیستان و بلوچستان،زاهدان،ایران
3 گروه مهندسی عمران، دانشگاه زابل، زابل، ایران
عنوان مقاله [English]
Utilizing recycled aggregates in concrete makes new feasibility study possible for recirculation of materials in construction industry. One of the considerable points in using concrete is the alteration of mechanical properties by changing specimen size that is called size effect. Compressive strength test was conducted on cubic samples with variable sizes and standard cylinder 15*30. Water absorption and penetrability tests were conducted on 10 and 15 centimeter cubic samples. By replacing the results of compressive strength test in modified Bazantt’s formula and applying linear regression, empirical coefficients of α and β were obtained. By applying these coefficients in the above formula, the ratio of compressive strength of cube sample to standard cylinder was obtained.
Examining the results for recycled concrete shows that by increasing the size of specimens, compressive strength declines which suggests the size effect on recycled concrete. In addition, adding 1.5% steel fibers to recycled concrete enhances the mechanical properties and durability. In addition, the size effect and differences between standard cylindrical and cubic compressive strength were decreased.