METHOD FOR CALCULATING THE COMPOSITION OF CELLULAR CONCRETE

Abstract

The analysis of existing methods for calculating concrete compositions was carried out. The characteristics and sequence of the calculation-experimental and experimental-calculation methods for the selection of concrete compositions are provided. The advantages and disadvantages of each of the methods are described. These methods are generalized by the general systemic cycle PDCA (Deming cycle), which is determined by the sequence of actions: P (plan) ‒ D (do) ‒ C (check) ‒ A (Action). It was established that for calculating the compositions of the cellular method there is no universal method, which would ensure the achievement of the required strength and average density at the same time. Based on the above, the aim of the thesis was formulated. The aim of the thesis is to develop a method for calculating the composition of cellular concrete, based on experimental-statistical models, which would ensure the production of concrete with the required properties while minimizing the cost of raw materials. A calculation algorithm, a block diagram and a computer program for designing cellular concrete compositions based on experimental-statistical modeling were developed. Using the example of the specified block diagram for calculating concrete compositions, the sequence of calculations is described in detail. The essence of the calculations is that the three-factor mathematical model of the property parameter of cellular concrete, which is supposed to be guaranteed, leads to a second order equation. After that, the roots of the equation are determined. They are substituted into a mathematical model and the composition of concrete is determined in natural values of variable factors. After that, the cost of the composition is determined, which is entered into the data array. Then one of the factors changes, according to the set step and the cycle repeats. At the last stage, the formed data array is processed and the composition with the minimum cost of materials is determined. Testing of the developed software was carried out by processing and calculating a three factor experiment. As a result, the composition of cellular concrete which provides the required strength of foam concrete with a minimum cost of materials, was determined.