Rate Sensitive Damage Behavior of Mortar in Compression

Abstract

This study investigates the knowledge on rate sensitive behavior in cracking process or damage behavior for brittle materials by testing concrete constituent, mortar at different rates of straining. The material response is compared based on tests of different strain rates. Cracking process of specimens are observed and recorded synchronously with loading and deformation response for the mortar at different rates of straining. For the mortar in a range of strain rates from 0.2–20,000,000 microstrains/sec, the compressive strength increases and its nonlinearity decreases with increasing strain rate. As the strain rate increases, the failure shows comparatively more violence and faster crack propagation, with an increasing number of cracks and fragments. The strain rate sensitive damage behavior indicates the reason why compressive strength, nonlinearity, viscoplasticiry and other mechanical properties of mortar and concrete are sensitive to the rate of straining.