This paper presents the evaluation of aggregate in gravel quarries at Qena .this evaluation depended on the physical properties such as density, water absorption, size fraction, shape and chemical properties as well as mineral contents in the aggregates. The mineral composition of sedimentary rocks was investigated using polarizing microscope and x-ray diffraction (XRD). The petrography examination of the gravel was carried out according to ASTM standard 295 to identify constitutes of the samples; identify the alkali-silica reactive ingredient such as opal, tridymite, chalcedony, crystobalite and alkali carbonates reactive rocks. These minerals react with alkalis in cement, leading to the expansion and cracking of concrete. Other components such as sulfides, sulfates, halites, iron oxides, clay minerals and anhydrites are examined, which might be present as coating and impurities. Coatings prevent the development of good bond between gravels and cement. Also, the transportation problem of these materials from quarries to destination sites has been applied. The transportation problem is one of the linear programming problems. There are different methods which are used to solve it such as: row minimum, column minimum, matrix minimum, north-west corner rule, Vogel's approximation method either manually or by computer software. The present study indicated that, gravel in most of the quarries studied is suitable for concrete making.
المشارك في البحث
قسم البحث
سنة البحث
2007
مجلة البحث
The 10th International Mining, Petroleum, and Metallurgical Eng. Conf.,
تصنيف البحث
3
ملخص البحث