One of the most significant parameters which should be considered by all engineers is improving structures’ strength subjected to lateral load. Steel shear wall whose duty is to affect lateral load (wind and earthquake) is a wall which consists of shear part. Application of low yield point (LYP) steel in shear walls allows the employment of moderate and/or stocky infill plates with low yielding and high buckling capacities, which can result in enhanced buckling stability, serviceability, and energy dissipation capacity of such systems. Infill LYP plate is used to improve shear wall behavior which leads to enhancement of stiffness. In the present research, infill plate with spherical appendages is applied, and its impact on plate stiffness, cyclic behavior and energy absorption are investigated. The spherical diameter has been chosen respectively 10 and 20 cm distributed with two patterns (diagonal and plus form). The best performance is for a LYP plate with a 10 cm spherical diagonal pattern.

The slope stability is a major concern to geotechnical engineers. Traditional methods of slope stability analysis have potentially ignored the influence of surface cracks. It is also known that seasonal rainfall and seepage through crack are closely related with slope failure. First, surface cracks provide special flow channels which increase the soil permeability and decrease the soil strength. Second, water-filled cracks apply an additional active force on the slope. Finally, cracks can create a part of the critical failure surface that has no shear strength. The objective of this paper is to investigate the influence of existing cracks on the stability of a cracked soil slope in different state. The effects of crack depth, slope angle and water-filled cracks on the stability of the cracked slope are explored. The analysis was conducted using the computer modelling programs Optum G2 to analysis of slope factor of safety. The results show that with increasing of slope angle the factor of safety decreases and this problem is significant in the slope with water filled cracks. Also, Factor of safety for all of slope angles in Dry and water filled cracks states with increasing the crack depth, decrease significantly.

In this paper, a modified three-dimensional element is introduced for limit analysis of RC structures, which considers more aspects of structural behaviour. Using the introduced element, the influence of stirrup confinement on the shear and moment resistance of RC beams is evaluated by lower bound limit analysis. To analyse and solve the relevant optimization problem, the semidefinite programming method, SDP, is employed. The modified Mohr–Coulomb yield criterion is utilized to constrain the concrete stress state. Beams with a constant amount of shear reinforcement per unit length, with different values of stirrup spacing, are studied. It means that they only differed in the effect of confinement induced by stirrup reinforcements. The performance of the proposed element is verified by comparing the results of numerical limit analyses with experimental results. This comparison revealed the efficiency and accuracy of the proposed model and the capability of the introduced element to take the effect of stirrup-induced confinements into account. After modelling and investigating the effect of stirrup confinement in load bearing of RC beams, a simplified equation for the design and practical purposes is proposed. Using this equation, the shear resistance of the beams could be modified for different stirrup space choices. The results obtained from this simplified equation are compared with numerical limit analysis and experimental results. The comparisons indicate the reasonable accuracy of the proposed equation.