The Effect of Vertical Members Arrangement on Temperature Load Analysis in Super-Long RC Frames

Super-long structural frames are more affected by the surrounding environment due to their interaction with the daily temperature changes. The designers must consider the forces produced by the daily temperature loads in addition to live and dead loads and enhance the structure to avoid structural cracks or failure. The building frame responds to force analysis according to the arrangement of its structural elements. The aim of this study is to investigate the effect of vertical element arrangement in terms of their shape, size, orientation, and location in super-long buildings on the distribution of forces while exposed to temperature loads. To achieve this aim, five frames were proposed in the form of a 4story 16.0 m height, 98.3 m length without using expansion joints, and 14.3 m width exposed to a positive temperature of +25 °C (daily temperature change), modeled using the Etabs 2020 program. The methodology employed in this study was developed based on the insights and recommendations gleaned from a comprehensive review of prior literature. Consequently, the research incorporated five distinct assumptions regarding the arrangement of vertical elements within the structural frames. The first model was the basic model, and its results were the basis for comparison with other models. The outputs of the frames′ deflection, bending moments diagrams, and reinforcement areas of nominated elements were presented and analyzed accurately to discover the factors affecting the frame performance in the models. The analysis shows that the temperature forces concentrated on the vertical and horizontal elements of the first floor in all frames, as the columns of this floor are more rigid because of their fixity at the bottom. Furthermore, the reinforcement quantities of structural elements increased based on the orientation, size, and location of the vertical elements. When the orientation of columns is in the same direction as the long span of the building, there will be an increment in the quantities to 26.06% in slabs, 124.26% in beams, and 48.76% in columns. In the case of replacing the corner columns with shear walls in the frames, the moment values increased in this area (39) times, and in the case of replacing the middle columns, they increased (9.1) times. This study will assist the structural designer in starting preliminary coordination with the architects to select the ideal arrangement for columns and walls’ location within the building to save on project costs.