The Use of Maturity Method for Estimating In Situ Compressive Strength of Concrete

摘要

This paper describes four projects which were built with the use of concrete monitoring system of early age compressive strength based on maturity method. The paper also deals with experiences and benefits which came from the usage of monitoring system in these projects. First two examples are bridge projects "Petersdorfer See" and "Seckachtal" from Germany. The third project is a retirement home in Germany and the last example is Czech project of office building Vlnena in Brno. Maturity methods for estimating early age compressive strength of concrete are known since the 1950s. These methods use the principle that compressive strength is related to age, temperature history and concrete mix properties. Before the use of this method, each different concrete mix in use needs to be calibrated. Then temperature and time are measured since the concrete is poured. Several systems using maturity method for estimating real time compressive strength are available on the market. The use of these systems helps to determine earliest possible time for stripping the formwork, loading the structure, application of post tensioning forces and other critical operations during the construction time.