Mechanical Characteristics and Stress and Strain Analysis of Concrete with Bonding Interface Under Impact Load

Abstract

To study the dynamic mechanical characteristic of steam cured concrete and self-compacting concrete bonding interface, a split Hopkinson pressure bar (SHPB) test was used to evaluate the dynamic properties of concrete with a bonding interface. The failure pattern and the characteristics of stress-strain curves and a constitutive model of concrete with a bonding interface were discussed. The results show that the impact destructions are associated with two forms of failures, i.e., the interface separation failure and concrete crushed failure. In interface separation failure, the peak stress, dynamic increase factor (DIF), peak strain, and impact toughness of concrete with a bonding interface increase with the increase of strain rate, and the concrete with a bonding interface shows a stronger strain rate sensitivity. In concrete crushed failure, there exist debonding deformation and crush deformation exist simultaneously. With the increase of strain rate, the accumulation and development of crack at the interface could make the interface zone play an energy relieving role in concrete with a bonding interface. The peak stress and the DIF of concrete with a bonding interface remain unchanged, while the peak strain and impact toughness both increase. The calculated data by the established dynamic constitutive model are similar to the experimental results, especially before the ultimate state of strain stress curves.

Keywords

• split hopkinson pressure bar (shpb) test
• bonding interface
• impact toughness
• stress-strain curve
• constitutive model