For loading rate on different positions of the structure, it was observed that the critical position would be under the explosion and towers adjacent. Also, by removing one or several elements of structures, the force is distributed in the whole structure. Explosion applied on the structure depends on the amount of the load and local effects. Forces and moments of the superstructure, responses and the stability of the structure under the applied loads were studied. For this purpose, different scenarios were investigated. In this study, a typical suspension bridge was modeled and analyzed under explosion load. This disproportionate collapse is due to the small initial local failure induced by unpredicted attacks, exhibiting that the structural system cannot resist the development of damage due to the insufficient load carrying capacity. Progressive collapse is a continuous spread of initial local failure from one member to another one, finally causing the collapse of the structure entirely or a disproportionately large part of it. The use of upgraded EVSs will allow for provision of a known maximum level of the explosion load should an explosion event occur in an EVS-equipped room. The efficiency of the suggested technical upgrade was proven by numerical experiments and indirectly by experimental studies aimed at exploring the physical processes associated with the opening of EVSs after an explosion accident. The suggested innovation excludes the possibility of a significant increase in explosive pressure due to an EVS response delay. This article offers an modest upgrade of the explosion-venting structure that provides an indoor pressure equal to the EVS start-to-open pressure. This aspect, however, prevents the widespread use of EVS at explosion-hazardous sites. Thus, each particular building requires individual selection of EVS parameters, which provide a safe level of excessive pressure in case of an explosive accident. It was demonstrated that the maximum explosive-pressure value inside EVS-equipped buildings depends on the EVS start-to-open pressure, the structure’s response rate (lag), and characteristic dimension of the premises. We provide results of model and full-scale experiments aimed at studying the influence of EVS parameters of blast-relief openings in explosion-hazardous buildings on the intensity of explosive loads. This article experimentally and theoretically demonstrates that the presence of blast-relief openings (windows) equipped with explosion-venting structures (EVS) allows explosive pressure to be reduced to a safe level (2–4 kPa). The study can work as an instruction for the application of movable lightweight bridges under explosion conditions. The-shaped design of diaphragms can reduce the discreteness between the bridge deck and the web, and result in effective energy absorption and good anti-blast performance for the bridge. The load capacity of the bridge model is mainly determined by the pin-jointed hinges and the webs. Based on the critical scaled distance, the explosion response can be intuitively divided into elastic deformation, plastic deformation, and local fracture. The research reveals that the bridge model has overall flexural deformation and complex local deformation patterns. Quasi-static three-point bending experiments were performed to evaluate the residual load capacity of the exploded bridge model. In this study, the blast response and damage mechanism of a movable lightweight metallic bridge model, composed of thin-walled skins,-shaped diaphragms and pin-jointed hinges model, were investigated by close-in explosion experiments and numerical simulations. For military bridges, the damage evaluation under close-in explosion is critical to judge their load capacity and service life.
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