Reliability-based live load reduction factors in axial force of columns in residential and office buildings
Publication Type
Conference Paper
Authors

According to most building codes, the axial live load effect in columns of multi-story buildings may be reduced by some reduction factor. The justification for such a reduction is that there is a small probability for having all spans and floors of the building occupied with nominal live load value. While this justification is jointly adopted by all buildings codes and standards, there are significant variations in the degree of reduction as allowed by these building codes. A probable cause for such significant variations is that these reduction factors were not based on reliability analyses, but rather on some extrapolation of different stochastic live load models to multi-story buildings. This study re-establishes the live load reduction factors based on reliability analysis, specifically, by maintaining the same reliability index for the columns. To achieve this goal, Monte-Carlo technique is utilized through the finite element software “ANSYS” on several thousand models of multi-story buildings. Live load, geometric and material variabilities are taken into consideration at many levels of statistical representation. The resulting stochastic F.E. analysis gives the probabilistic distribution of axial live load in columns, which is then used to re-calculate the characteristic “nominal” value for the axial live load based on a reliability index. The obtained “nominal” value of axial live load in columns is then compared to the axial live load value obtained using nominal load value as given in codes and standards distributed uniformly over all spans and floors of the building. Based on this comparison, the reduction factor is readily defined as the ratio between the two values. The resulting reduction factors are then compared to those given in codes and standards and conclusions are then drawn.

Conference
Conference Title
The First International Conference & Expo on Innovation and Sustainability in Engineering & Technology, themed "The Future of Engineering & Technology Education"
Conference Country
Palestine
Conference Date
June 14, 2023 - June 15, 2024
Conference Sponsor
جامعة النجاح الوطنية
Additional Info
Conference Website