Numerical and experimental analysis of the behavior of structural elements composed of double lattice panels

Resumo An experimental and numerical investigation was conducted into the factors that interfere in the shear strength of the concrete-concrete interface in structures composed of double lattice panels subjected to direct shear stress. The experimental program consisted of testing 26 direct shear models with varying widths of concrete fi lling of 7 cm, 9 cm and 13 cm, with smooth and rough interfaces, as well as diff erent concrete compressive strengths in the fi lled region. The numerical modeling, which was performed with ANSYS software, employed solid fi nite elements, bar elements and contact elements, taking into account the non-linearity of the materials involved. The analyses of the experimental results under direct shear indicated that the transfer of stresses at the interface occurred with loss of adhesion. The numerical simulations indicated that the higher the geometric ratio of reinforcement the higher the direct shear strength of the structural model. In general, the slip of the models with smooth interfaces was 2 or 3 times greater than the models with rough surfaces. Numerically, the models with smooth interfaces showed a 36.61% gain in shear strength when the compressive strength in the region fi lled with concrete increased from 20 MPa to 28.4 MPa.