379 SIMULATION OF EXPERIMENTAL PARAMETERS OF RC BEAMS BY EMPLOYING THE POLYNOMIAL REGRESSION METHOD B. Sayin, 1* S. Sevgen, 2 R. Samli 2 Keywords: computer simulation, regression analysis, experimental study, RC beam, CFRP A numerical model based on the method polynomial regression is developed to simulate the mechanical behavior of reinforced concrete beams strengthened with a carbon-fiber-reinforced polymer and subjected to four-point bending. The results obtained are in good agreement with data of laboratory tests. 1. Introduction The evaluation of structural member properties according to an earthquake-prone country with its location on several plate boundaries can be an important matter. Therefore, experimental studies have a critical and important role in scientific research. Many experimental studies have been performed to evaluate the mechanical behavior of RC (reinforced concrete) beams in buildings. Although the methods used to produce results with a high accuracy, they are appropriate not always because of some limitations. Researchers are in the quest of alternative methods to experimental studies that could save them from the limitations, such as a high cost, consumption of time and labor and speed up the experiments. Computer simulation is the most important alternative to them. In the literature, various estimation methods, such as artificial intelligence (artificial neural networks, fuzzy logic, genetic algorithms, and ant colony) and mathematical modeling (regression and response surface methodology) are used for simulations, and successful results are obtained [1-10]. In this paper, a numerical model able to accurately predict the load-carrying capacity, deflection and test duration of RC beams strengthened with CFRP subjected to four-point bending is presented. At the first stage, an experimental program Mechanics of Composite Materials, Vol. 52, No. 3, July, 2016 (Russian Original Vol. 52, No. 3, May-June, 2016) 1 Department of Civil Engineering, Istanbul University, 34320, Turkey 2 Department of Computer Engineering, Istanbul University, 34320, Turkey * Corresponding author; e-mail: barsayin@istanbul.edu.tr 0191-5665/16/5203-0379 © 2016 Springer Science+Business Media New York Russian translation published in Mekhanika Kompozitnykh Materialov, Vol. 52, No. 3, pp. 535-546 , May-June, 2016. Original article submitted July 21, 2015. DOI 10.1007/s11029-016-9590-3