Abstract
The author measured drying shrinkage strain on six kinds of concretes. These six kinds of concretes have different unit water content, water cement ratio and types of coarse aggregate. In general, the drying shrinkage strain is under the influence of unit water content. Previously, it was known that the drying shrinkage strain of concrete mixed limestone aggregate was smaller.
From the results of this experiment, the drying shrinkage strains measured with embedded strain gauge showed stabilized values than the one used on the surface of concrete. The drying shrinkage strains values of embedded strain gauge showed about 55μ higher than the surface strain gauge. It was found that the drying shrinkage strains was related to（1）1.1 times of limestone volume and（2）unit water content －8％ that of limestone volume. Also, this coefficient of correlation as per regression line is ranged between 0.9～0.97. Therefore, the drying shrinkage strain showed strong relationship with limestone content and the unit water content. In case of varying the limestone content, the author made cleared the fact that the drying shrinkage strains of the concrete mixed with limestone aggregate showed almost the same values that of concrete mixed with different kinds of crushed stone.
