Search

This study investigates the effect of continuous rectangular spiral shear reinforcement on reinforced concrete slabs under low-velocity conditions, crucial for scenarios such as landslides or vehicular collisions. By combining experimental and finite element analyses using ABAQUS, this research assesses the effectiveness of this reinforcement method. The experimental setup involves subjecting slabs to impact loading with consistent energy levels using a drop weight system. Various parameters, including acceleration time, strain-time in steel and concrete, and failure mode, are carefully monitored throughout the study. Results demonstrate a notable 216.13% improvement in energy absorption and a 43.70% increase in impact ductility compared to control specimens, reflecting higher rigidity and stiffness in spiral-reinforced specimens, as evidenced by elevated maximum acceleration values. Specimens with continuously rectangular spirals exhibit less severe surface damage upon complete failure, emphasizing their enhanced impact resistance. Diagonally arranged spiral reinforcements notably reduce damage, displacement, and stress. These findings highlight the significant potential of continuously rectangular spirals in improving the low-velocity behavior of reinforced concrete slabs, offering valuable insights for structural design and reinforcing systems. Additionally, using ABAQUS finite element analysis validates experimental findings, providing efficient insights into structural behavior under dynamic conditions.

Reinforced concrete flat solid slabs may experience explosive and impact loads. Reinforced concrete flat solid slabs have been studied under static and dynamic loads. Researchers have widely explored numerous reinforcing strategies to strengthen RC slabs exposed to impact loads, yet gaps remain. Internal anchorage stirrups (W-stirrups shear reinforcement) is still rarely used to strengthen slabs against impact loading. Consequently, this study emphasized the influence of W-stirrups shear reinforcement on the dynamic response and failure modes of RC slabs subjected to impact loads.The first part examined the impact behavior of fully fixed RC flat solid slabs reinforced with W-stirrups shear reinforcement experimentally. Slabs were impacted using portable drop-weight testing equipment. Six 800-x-800-x-90-mm RC slabs were made. Three samples were reinforced with a W-stirrups orthogonally oriented in two directions, whereas three controls were without any type of strengthening. The eccentric vertical displacement of slabs, strain at four points on the W-stirrups, two on main steel, and two on concrete, and acceleration at one point over a slab were measured; also, failure modes were monitored.In the second section, ABAQUS software was used to generate finite element models of slab study samples. Numerical model results matched experimental results. Thus, the suggested finite element model may assess reinforced RC slabs under low-velocity impact loads. Finally, a parametric study was conducted in the third part to address the issue of over-reinforced design in slabs with W-stirrups. The parametric study aimed to determine the optimal steel ratio of flexural and shear reinforcement and its influence on the behavior of RC flat solid slabs reinforced with W-stirrups shear reinforcement.

Concrete is brittle; hence, it is incredibly likely that concrete buildings may fail in both local and global ways under dynamic and impulsive stresses. An extensive review investigation was carried out to examine reinforced concrete (RC) slab behavior under low-velocity impact loading. Significant past research studies that dealt with experimental and numerical simulations and analytical modeling of the RC slabs under impact loading have been presented in this work. As a result, numerous attempts to define failure behavior and to assess concrete structures’ vulnerability to lateral impact loads have been made in the literature. Based on analytical, numerical, and experimental studies carried out in previous research, this article thoroughly reviewed the current state of the art regarding the responses and failure behaviors of various types of concrete structures and members subjected to low-velocity impact loading. The effects of different structural and load-related factors were examined regarding the impact strength and failure behavior of reinforced concrete slabs reinforced with various types of strengthening procedures and exposed to low-velocity impact loads. The reviews suggested that advanced composite materials, shear reinforcement, and hybrid techniques are promising for effectively strengthening concrete structures.