Ensuring stability of the slope of the rock massif under the impact of additional load on it

Abstract

Purpose. The purpose of the research is to substantiate and establish the parameters of the protective structure of bored piles for strengthening the instrumental rock massif of loams and modeling the state of the slope under the influence of external additional load. The methods. The complex research methodology was applied, which consists in the analysis of the existing scientific data on slope reinforcement, analytical determination of the parameters of the protective structure, modeling the behavior of the rock massif in its natural, loaded and fixed states, comparative analysis of the massif stability coefficients and development of new engineering solutions to ensure the normative stability of the slope. Findings. According to the results of modeling the state of the final position of the slope of the side of Zhidachevsky loam deposit under additional external load from the action of motor transport, it was found that the minimum value of the stability coefficient is kc= 0,911, that is, the studied rock massif is unstable. It is proposed, to ensure the stable condition of the studied section of the rock massif, to install a protective structure of one row of bored piles. In accordance with the characteristics of the pile, its length below the level of the potential collapse surface was calculated and the total length of the piles was determined. Modeling showed that the use of this design increased the stability coefficient to kc=1,099. In order to fulfill the normative requirement to ensure the stability of slopes of rock massifs (kc≥1,2), it is recommended to apply a reinforcing structure of two rows of bored piles, the distance between which is 4,5 m, the length of the wells of the 1st row – 16m, the 2nd row – 20m. In this case, the slope stability coefficient is kc=1,218. The originality. The stability coefficients of the loam rock massif in its natural, loaded and fixed states were obtained and the graph of change of this coefficient along the length of the cross-section of the investigated block at the use of the protective structure was plotted. Practical implementation. A new constructive solution of the protective structure from bored piles for providing normative stability of the dashboard massif at the quarry of Zhidachivka loam deposit is offered.