In this paper, an orthogonal braided glass fiber composite sandwich panel with a PVC foam core and dimensions of 150 mm×100 mm×26 mm is selected as the research object in order to study the impact mechanical properties of composite sandwich panels. The dynamic response and residual compressive strength of the panel under single-point low-velocity impact are then analyzed.

First, a series of drop hammer impact tests are conducted to study the failure mode, impact force-displacement response and energy absorption characteristics of the panel under different impact energies. Next, quasi-static compression experiments are conducted to investigate the maximum compression load capacity and residual compressive strength under impact damage.

There are significant differences in the failure modes and impact force-displacement characteristics of the sandwich panel under different impact energies. The core mainly absorbs impact energy through compression deformation. As the impact energy increases, the maximal impact force, dent depth and absorbed energy of panel gradually increase, while the maximum compression load capacity and residual strength decrease after impact. The damage degree of the impacted composite sandwich panel determines its residual compressive strength.

The findings of this study can provide valuable references for the impact resistance design of naval ship structures.