Equivalent vehicle load factors for parking garage members

Abstract

The primary focus of this dissertation is the comprehensive investigation of vehicle load effects on parking structural members. For this purpose, a simplified, but effective, algorithm to obtain critical design moments for parking garage members is developed. Maintaining the uniformly distributed load concept generally adopted in the design of building structures, this dissertation introduces the equivalent vehicle load factors which can simulate the vehicle load effects without taking additional sophisticated numerical analyses. The live loading of parking structures can be quite cumbersome, requiring many different load case applications of wheel loads to determine the maximum design moments. Accordingly, the application of concentrated wheel loads, while maintaining wheel distance, has been frequently ignored in spite of its importance. The live loading of parking structures is not only computationally demanding but also requires much effort on the part of the structural designer, since each structural components must be designed to sustain live loading. Any methods or guidelines that clarify the effect of vehicle loads on parking structural members are certainly advantageous to the structural designers. After choosing a standard design vehicle of 2.4 tons through the investigation of small to medium passenger vehicles made in Korea, finite element analyses for concentrated wheel loads were conducted by referring to the influence lines for frame elements and influence surfaces for slab members. Based on the obtained member forces, the equivalent vehicle load factors for parking garage members which represent the ratios of member forces under vehicle loads to those under uniformly distributed loads is determined. In addition, the relationships between the equivalent vehicle load factors and sectional dimensions were established by regression and used to obtain the design moments by vehicle loads. The member forces calculated by the proposed method are compar...