Bài báo khoa học

Introduction: reinforced concrete (RC) columns are one of the main bearing parts of the building, it is responsible for receiving loads from beams, floors, .. and transmitting to the foundation. During the working process, the column is mainly subjected to centered or biaxial compression, and the calculation process for the column subjected to biaxial compression is quite complicated. The purpose of the study was to propose a simpler and more applicable method to calculate the stress-strain state of short RC columns with biaxial compression. provide post-design verification as well as support a simple analysis method for programming calculation of biaxial compressed columns. This study method has combined many theories to create balanced equations through mathematical matrices, the help of Mathcad software has also been mentioned. Instead of considering the balance equations through the nodes, this study considers the balance through the centroids of the concrete and reinforced elements. The bilinear stress-strain relationships of materials (concrete and reinforcement) are applied in this study. In addition, the finite element-based simulation method has been also studied to compare with the results of the analytical method. The problem has been conducted with 3 different load levels for both methods and gave the color spectrum of stress and strain on the cross-section of short RC column subjected to biaxial compression. The results have shown the stress and strain on the cross-section, showing the location of the tensile, compression, and dangerous stress values in the cross-section. The error of the analytical method with the numerical simulation method by ANSYS software is less than 5%. Thus, the analytical method with the bilinear model of the material gives quite accurate and acceptable results for application to the design process of reinforced concrete short columns.