عنوان مقاله [English]
نویسنده [English]چکیده [English]
This article deals with a tentative method of concrete compression and the measurement of compressional resistance. The subject of free fall for concrete compression has not received adeqaute attention so far. In this research, the compresional resistance of compressed concrete with free fall is compared with the compressed concrete by trembling bed. To do so, 176 cylinderical testing case with dimensions of 30*15 cm were made. The concrete casting was accomplished in the laboratory of the technical college in 88 stages. Construction of the testing case was on the basis of suggested factors effective on the result of tests including the amount of compression energy, the height and time of fall in every energy, the ratio of water to cement (W/C) and gravel to sand (G/S). All of the testing cases (after testing) were broken under press machinery at the age of 28 days simultaneously. The result obtained from breaking of the free fall and vibrated testing case accomplished by press machinery have been represented in different tables and charts.