METHOD FOR FORMING NON-DISTURBED GRAVEL CORE FOR THREE-AXIS COMPRESSION TEST

摘要

PURPOSE:To provide a non-disturbed gravel core having excellent quality readily from frozen blocks by freezing a gravel sample which is sampled at normal temperature. CONSTITUTION:A frozen block is conveyed out of a refrigerating room and set on a base stage 15 of a boring machine 11. Then, a circulating pump 25 is driven, and a solenoid valve 23 is controlled. Liquid coolant which is used in a machine 11 is kept at low temperature of about -10 deg.C - -20 deg.C all the time during boring. The required number of samples having the specified diameters for the machine 11 are taken out. The boring cores are covered with Saranwrap immediately after the pulling out. The cores are inputted into a constant- temperature/constant-moisture tank and stored at -20 deg.C. Then, the core is cut into the specified lengths with a core cutter. At this time, the low-temperature liquid coolant which is used in the machine 11 is made to flow to the cut parts so as to prevent the temperature rise at the cores which are being cut. When the cutting is finished, the cores are immediately inputted into the constant-temperature/constant-moisture tank and stored at 20 deg.C. Then, the frozen bodies under test are taken out of the constant-temperature/constant-moisture tank and set on a three-axis cell. After constraining pressure is applied, thawing is performed. Then, the test is conducted in accordance with a general three-axis compressing test method.