Influence of High Water Pressure on Static and Dynamic Compressive Strength of Concrete

In this paper, an experimental study was conducted on the influence of water pressure on concrete strength. Specimens were put in a self-designed device, applying 0-4 MPa water pressure on concrete, and then taken out for both static and dynamic compressive tests. Results showed that high water pressure caused inevitable damage to concrete, leading to 13.4% reduction in strength under 4 MPa water pressure. Specimens with lower strength grade were damaged more severely while under the same water pressure. Also, as water pressure increased, the moisture content of concrete grew linearly, and the trend for specimens with higher compressive strength was slower. A correlation was established between the water content increment and the reduction rate of strength. Moreover, the dynamic compressive strength decreased as water pressure increased but still higher than the static strength, illustrating an apparent strain rate effect. Meanwhile, water pressure and moisture content increment barely had any influence upon DIF within the testing conditions. Furthermore, equations for calculating both static and dynamic reduction rates of strength were built, based either on water pressure or on moisture content increment caused by that. Equations for strength prediction were also provided.