Evaluation of Laboratory Equipment for Freezing and Thawing of Concrete

摘要

The objectives of this study were: (1) To determine the ability of the equipment to estimate the performance of concrete, and (2) To determine the potential application for rapid freezing and thawing tests of aggregate. (Equipment found suitable only for freezing and thawing tests of concrete and aggregate in concrete). The equipment is a commercial automatic freezer similar to that used in a number of laboratories. Concrete for test was prepared with various materials, air contents and proportions. Some of the conclusions of these tests are as follows: (1) The apparatus is capable of a reproducible cycle meeting the requirements of ASTM C 291. (2) Use of equipment in accordance with ASTM C 290 can result in damage to both specimen and containers. (3) Mechanically, the performance of the equipment was excellent. (4) Tests conducted with this equipment classified concrete consistent with service record. (5) The apparatus gives excellent estimates of sensitivity of aggregate to freezing and thawing. (6) Concrete without air fails after 10-20 cycles. (7) Limits for terminating the test set in ASTM C 291 are satisfactory. (Author)