Damage assessment of prefabricated prestressed channel slab under plane charge blast

•Designed prefabricated prestressed channel slab could resist low-altitude nuclear blast without plastic damage.•The plane charge blast test with long positive duration (more than 2 s) was successfully implemented.•Positive duration was related to the quality of the overlying soil and the air shock wave overpressure design value.•Theoretical calculation and ABAQUS simulation results were verified by experimental data.