## 1 Introduction
### Background
One study [40] considered the local replacement of coarse concrete aggregate with battered RT seed shells. Compositions with the addition of natural raw materials in the amount of 5%, 10%, 15% and 20% of the volume of concrete were considered. The cubic strength of concrete in compression and TS in twisting were studied. The consequences achieved were compared with the control composition, consisting of ordinary concrete, not containing the shell of the seeds of the RT. The consequences of this study presented that the compressive strength and TS of concrete in twisting when replacing CA with RT seed shells by more than 10% of the volume of concrete decreased in direct proportion to the amount of RT seed shells. When replacing CA with a natural analogue in an amount of less than 10%, the decrease in the studied strength features was insignificant and suitable for the needs of modern construction. In this study, only two strength parameters of concrete were considered, and the factor of reducing the weight of concrete and changing its heat-conducting properties was not considered. In ref. [41], the features of self-compacting concrete were considered with the complete replacement of CA with RT shells, covered by vulcanization with two layers of latex, while varying the ratio of cement, sand, and crushed stones. The mobility of the resulting mixture and cubic strength of concrete were considered. According to the consequences of the study, it was revealed that the ratio cement:sand:coarse aggregate equal to 1:0.94:0.046 is optimal. This study considered only one strength parameter and did not consider the weight of the resulting composition. The study [42] adds to the growing body of literature on solutions to problems associated with integral bridge fills. The results obtained in this paper and other physics models and field instruments for mixed tire and soil backfill suggest a new side ground pressure coefficient for integral bridges based on the tire content and mixing area with the wall. Recycling tire rubber in soil mixtures significantly reduces the stress factor, earth equivalent peak pressure factor and settlement after 120 cycles [42]. The use of waste rubber tires in concrete is still scattered and unclear. Consideration in ref. [43] of important areas of concrete freshness, durability and strength properties, as well as microstructures, is promising. However, there are certain obstacles that prevent the use of such waste as aggregate in large quantities, such as the poor structural strength of rubber and poor bonding to the cement matrix. Rubber, however, exhibits mechanical strength comparable to reference concrete, up to 20% [43]. The study [44] was carried out to fill an existing gap in the literature on the evaluation of the compressive strength of concrete containing binary additional cementitious materials. The effect of different substitution levels of three different common pozzolans (metakaolin, zeolite, and fly ash) in concrete mixes was studied. The optimal level of substitution for the design of binary mixtures was 10% by weight of cement. The developed model for predicting the compressive strength of concrete containing binary additional cementitious materials had an accuracy in terms of MSE of 0.0017 for the validation data. In addition, more than 42% and 94% of the data were predicted with an error of less than 2% and 10%, respectively. The effect of various combinations of additional cementing materials with any arbitrary chemical composition at any age from 3 to 365 days can be predicted with high accuracy using the MLP network proposed in [44]. Of no small importance are the indicators of the durability of rubber concrete, which depend on the content of rubber in concrete and the method of pre-treatment of rubber [45; 46; 47; 48].