نوع مقاله : مقاله پژوهشی
نویسندگان
1 رئیس مرکز تحقیق و توسعه سیمان تهران
2 کارشناس آزمایشگاه کنترل کیفیت سیمان تهران،
3 رئیس آزمایشگاه فیزیک مجتمع صنعتی سیمان تهران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Grading is one of the most important characteristics of cement, which has a great impact on its performance in fresh and hardened concrete. The most common methods of cement grading monitoring are determination of residue through 200, 90 and 45 micron sieves, fineness test by Blaine method and Laser Grading. Combining the results of these tests is the best way to control cement grading. In this study, it was tried to introduce the main indices of cement grading and its effect and deal ranges. Therefore, through a laboratory operation, 204 samples of type 2 Portland cement were prepared and their physical characteristics were determined and laser grading was done. Then, by making concrete mixtures with constant workability (slump 0.8±0.5 cm), the performance of cement samples with various grading in concrete mixtures was investigated. Among the most important results in this extensive study, the clear effect of increasing the amount of 3-30 micron particles and the uniformity coefficient of cement on the compressive strength of concrete and mortar and the presenting of the relationships can be mentioned.The compressive strength of 28-day standard mortar is approximately equal to half of the amount of 3-30 micron particles and constant number 22 MPa.
کلیدواژهها [English]
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