Feasibility of using of accelerated test methods for determination of frost-resistance for concrete

摘要

The article presents the results of studies of innovative materials in the field of testing frost resistance. In fact, present accelerated methods for the determination of concrete frost resistance have high labour consuming and low effectiveness. Moreover there is no such accelerated methods which can be sufficiently applicable fro different innovative concretes, for example, concretes with SAP or self-compacting concrete and so on. Therefore, it is highly important to investigate new accelerated test method with high operability, efficiency and sufficient precision. Previously, two new methods were developed. The main purpose of the research is to compare these methods by evaluation of their technology and accuracy and, consequently, to identify the more sustain and efficient one. First method is based on estimation of energy release due to mechanical fracture and thermo cycling. Second method consists of the calculation value z (relation between relative decreasing of strength and relative strain in the direction perpendicular to compression) and replacement of thermo cycles by mechanical cycles. Both methods have high operability and do not take a lot of time, in was tested on the 10 specimens made of concrete and results were compared with values derived by standard method.