Numerical Study on Blast Resistance of Precast Concrete Frame Structures Under Internal Explosions

With the development of precast concrete (PC) construction techniques, the threat of accidental or terrorist explosions on PC frame buildings cannot be neglected. Based on the structural hybrid modeling approach combined with the Multi-material Arbitrary–Lagrangian–Eulerian (MM-ALE) method, a high-fidelity numerical simulation approach is proposed for predicting the dynamic behaviors of entire PC frame structures under explosions. First, by reproducing the typical explosion tests on PC columns with grouting sleeve connections and PC slabs with composite connections, the reliability of the modeling approaches for the connections of PC members was verified. Second, the field explosion test on the autoclaved aerated concrete (AAC) wall was carried out to examine its dynamic behavior under blast loadings, and the corresponding modeling approach was validated. Then, a hybrid finite element model of the prototype PC frame structure was established by integrating the validated modeling approaches of the grouting sleeve and composite connections, as well as AAC walls. Finally, the corresponding dynamic behaviors were studied under different detonation positions and charge weights, and the blast resistance between the PC and RC frame structures was further compared. It derives that, (i) the explosions on different floors induce the approximate damage scopes to the PC frame structure; (ii) the PC frame structures suffer moderate damage under the explosion of 200 kg TNT, while suffer slight damage under the explosion of 50–100[Formula: see text]kg TNT; (iii) the PC and RC frame structures exhibit the comparable blast resistance with the similar percentages of damaged rooms in total.