Nondestructive testing of mortar specimens using the microwave free-space method

The results of nondestructive testing of mortar specimens using a simple and inexpensive microwave measurement system are presented. Temporal dependencies of amplitude of reflection and transmission coefficients at x band for the specimens made with different water-to-cement ratio (w/c) are given. It is shown that there is a strong correlation between the measured results and w/c. The results also demonstrate the influence of curing conditions and the effects of aging