Flexural behavior of innovative multifunctional concrete sandwich shells with different types of connectors

Abstract This study develops an innovative multifunctional concrete sandwich shell based on a combined experimental and finite element (FE) study on its flexural behavior. The sandwich shell is made up of inner and outer concrete layers connected by connectors, with a middle functional layer that provides various functions such as insulation, acoustic, and vibration control. Bending tests were conducted on four groups of specimens, including three groups of sandwich shells with different types of connectors, that is, truss, grid, and plate connectors, and one reference group of solid shells. Loads, displacements, and strains were recorded during the tests. The FE analysis showed good correlation with the experimental results. Furthermore, a parametric study was conducted using the FE model to evaluate the influence of different parameters, such as middle layer thickness and number of connectors. The results show that the performance of the sandwich shell is comparable to, and in some cases better than, that of the solid shell, depending on the type of connectors used. This study provides a proof of concept for the sandwich shell and establishes a prototype structure for future research.