Contents lists available at ScienceDirect International Journal of Impact Engineering journal homepage: www.elsevier.com/locate/ijimpeng Numerical investigation of impact injury of a human head during contact interaction with a windshield glazing considering mechanical failure Jiawen Wang a , Runhao Wang a , Wei Gao ⁎ ,a , Shunhua Chen ⁎ ,b , Chengyong Wang a a School of Electromechanical Engineering, Guangdong University of Technology, Guangzhou, China b Department of Systems Innovation, The University of Tokyo, Japan ARTICLE INFO Keywords: Pedestrian head injury Automotive windshield glazing Intrinsic cohesive zone model Finite element method Pedestrian-vehicle accident ABSTRACT In the context of a pedestrian-vehicle accident, the head of an adult pedestrian normally impacts the automotive windshield glazing, which mainly accounts for the pedestrian’s death. Consequently, it is of vital importance to investigate the head impact injury behaviour during interaction with the windshield glazing for the purpose of pedestrian safety protection. This paper presents a numerical approach to achieve this end. An intrinsic cohesive zone model is used to simulate the two main impact failure patterns, i.e., glass fracture and glass-PVB debonding, of the windshield glazing. The capacity of this model is validated by comparing the simulation results of a windshield glazing impacted by a pedestrian dummy headform with experimental ones in terms of acceleration histories. A finite element head model with detailed biomechanical features is established, whose effectiveness is validated with the aid of the experimental and simulation results in literature. Finally, parametric studies are performed to investigate the effects of impact velocity, head impact position, and windshield impacted location on head injury behaviour. 1. Introduction In recent decades, pedestrian safety protection in the context of pedestrian-vehicle accidents has remains to be worldwide concern. In such an accident, it was reported that the head and the lower ex- tremities are the two body regions that are most likely to be injured for an adult pedestrian [1,2]. Compared with the lower extremities, the head injury is more deadly. During a collision process, the head of an adult pedestrian normally impacts the windshield area, which is the leading cause of severe head injuries [3–5]. As a result, the headform- windshield impact test has become one of the essential components of New Car Assessment Programmes (NCAPs), e.g., European NCAP [6]. In addition, the impact failure patterns of a windshield glazing contribute to the traffic accident reconstruction [7]. The research approaches for head-windshield impact analysis mainly fall into two groups: experimental investigations and numerical simulations. Regarding the first group, a pedestrian dummy headform was projected to a windshield glazing during experiments, where high- speed cameras and acceleration sensors were usually employed to re- cord the failure process of the windshield laminated glass and the im- pact acceleration histories [8,9]. Some other representative impact failure experiments of laminated glass can be found in [10,11]. Though experimental approaches normally provide trustable results, some mechanical parameters, e.g., stress waves and energy histories of the windshield and dummy headform, are intractable to be acquired and the result data are limited. In contrast, numerical simulations provide freedoms for parametric studies of mechanical behaviour in head-windshield impact tests. In this regard, the impact failure, including glass fracture and glass-PVB de- bonding, of the windshield glazing is of special interest. As summarized in a recent review [12], the numerical approaches for the modelling of glass fracture mainly include the element deletion method [8,9,13–16], the combined discrete/finite element methods [17–22], the cohesive zone models (CZMs) [23–27], and the extend finite element method [28,29]. Among them, the CZMs have received increasing attention in recent years due to simplicity and effectiveness to describe the onset and propagation of glass cracks. The existing CZMs can be divided into two categories, i.e., the intrinsic and extrinsic models. The main dif- ferences between them in terms of finite element implementations lie in the strategies to insert cohesive elements (CEs) into the finite element model. Compared with the extrinsic CZM, the intrinsic approach inserts CEs into the common surfaces between finite elements prior to simu- lations, which does not require topology data manipulation along with crack growth. However, special attention needs to be paid to the pos- sible non-physical phenomenon, i.e., artificial compliance. The intrinsic CZM normally uses a penalty approach to enforce the interface https://doi.org/10.1016/j.ijimpeng.2020.103577 Received 18 September 2019; Received in revised form 10 March 2020; Accepted 20 March 2020 ⁎ Corresponding author. E-mail addresses: gaowei@gdut.edu.cn (W. Gao), sh_chen@save.sys.t.u-tokyo.ac.jp (S. Chen). International Journal of Impact Engineering 141 (2020) 103577 Available online 01 April 2020 0734-743X/ © 2020 Elsevier Ltd. All rights reserved. T