Optimizing Lateral Stiffness in High-Rise Structures: Investigating the Optimal Outrigger Location under Wind Load

Abstract

With the proliferation of high-rise structures worldwide, meeting the stiffness demands imposed by earthquake and wind-induced lateral loads has become a crucial aspect of their design. While traditional solutions like shear walls and bracing systems effectively address stiffness requirements, their cost-effectiveness diminishes as the height of the structure increases. To overcome this challenge, this research proposes the implementation of an outrigger system, offering enhanced lateral stiffness while minimizing costs. The objective of this study is to identify the optimal location for the outrigger system in high-rise structures under wind load conditions. A comprehensive investigation of 100-story high-rise structures was conducted using the outrigger system, with the outrigger location varied along the height of the structure. The performance evaluation of each structure was carried out using various response parameters, including top-storey displacement and storey drift ratio. The ETABS software was employed for structural analysis, considering wind load as the primary lateral load scenario.The results of the analysis demonstrated the significant influence of outrigger placement on reducing lateral displacement and improving overall structural stiffness. Structures equipped with four outriggers exhibited an approximate 19% reduction in lateral displacement compared to those without outriggers. These findings highlight the efficacy of the outrigger system in mitigating the adverse effects of lateral loads and enhancing the structural performance of high-rise buildings.In addition to the performance evaluation, a thorough cost analysis was conducted to assess the economic viability of the outrigger system. Factors such as construction, material, and maintenance costs were considered to compare the cost-effectiveness of the outrigger system with traditional solutions like shear walls and bracing systems.This research contributes to the optimization of high-rise structure design by providing valuable insights into the effectiveness and cost-efficiency of outrigger systems. The identification of the optimal outrigger location enables designers and engineers to achieve improved structural performance while reducing reliance on more expensive solutions. The outcomes of this study serve as a valuable reference for future high-rise construction projects, facilitating informed decision-making in the pursuit of safe, cost-effective, and resilient structures.