Experimental and numerical investigation on the attenuation of blast waves in concrete induced by cylindrical charge explosion

• Published in: International journal of impact engineering 2023-04, Vol.174, p.104491, Article 104491
• Main Authors: Gao, Chu, Kong, Xiangzhen, Fang, Qin
• Format: Article
• Language: English
• Subjects: Aspect ratio; Concrete; Cylindrical charge; Depth of burial; Peak stress
• ISSN: 0734-743X; 1879-3509
• DOI: 10.1016/j.ijimpeng.2023.104491

•Blast wave test in concrete with cylindrical charges considering aspect ratio and depth of burial is conducted.•The influences of charge shape and depth of burial on blast waves in concrete are quantitatively analyzed.•Two stages are identified to characterize the relation of coupling factor for peak stress with distance.•Several empirical formulas useful for blast-resistant design are presented. Concrete material is widely used in military facilities to resist the deliberate attacks by earth penetration weapon (EPW). The charge of EPW is more nearly cylindrical than spherical in geometry, and its explosion usually occurs in a certain depth of burial (DoB). To quantify the influences of charge shape and DoB on blast waves in concrete, experimental and numerical investigation on the attenuation of blast waves in concrete induced by cylindrical charge explosion is carried out in the present study. Firstly, a set of blast wave test in concrete with cylindrical charges is conducted to provide fundamental data including the stress-time histories and failure in concrete with the considerations of aspect ratio and DoB. Then based on the concrete material model by Kong and Fang and LS-DYNA's multi-material ALE algorithm, the attenuation of free-field blast waves in concrete generated from spherical charges and cylindrical charges with different aspect ratios is numerically investigated in detail. Finally, the influence of DoB on the peak stress directly below cylindrical charges is discussed and a coupling factor for peak stress is proposed. Several empirical formulas are presented based on dimensional analysis and curve-fitting the numerical data, including the critical distance beyond which the charge shape effect could be neglected, coupling factor for peak stress and peak stress from cylindrical charges with varied aspect ratio under different DoBs, all of which are useful for blast-resistant design.