LANDSLIDE STABILISATION AND REHABILITATION MEASURES ON THE REGIONALEN ROAD R-1202 MAVROVO - DEBAR, NORTH MACEDONIA

Abstract

Tectonic displacements, terrains with cracked and decomposed rocks, climate change and intense rains are the main factors that cause the emergence of new geological processes. These phenomena can cause damage to road infrastructure facilities. Such a
phenomenon is registered on the regional road R-1202 Mavrovo-Debar, in the western part of North Macedonia, where on one of the lanes on the side of the slope there is a subsidence of the road construction. In this paper measures for stabilisation and rehabilitation of the landslide on the regional road are presented. This particular terrain is characterised by steep slopes, and in addition to the terrain instability reasons stated above, there is an inadequate maintenance of the drains and canals that are a part of the road structure. Therefore, the problem has been studied and recommendations are given for stabilisation and rehabilitation measures. The proposal is to build a structure to relocate and strengthen the unstable zone consisting of a slab founded on piles that will transfer the load to the lower layers. For this purpose, two software programs are used: “Slide”, which analyses the stability by boundary equilibrium methods, and “Plaxis 2D”, which is used to calculate deformations and straining. According to the results obtained from “Slide”, the safety factor value Fs = 0.988 proves that the slope is not stable and there is a need for slope reinforcement, as well as rehabilitation of the road with reinforced concrete slabs and piles. While the design of the technical solution is simulated in several phases, according to the obtained results it is concluded that valid results are obtained from the last phase of exploitation and the maximum deformations Utot = 14.23 mm are shown and they occur in the pile capping beam. The horizontal and vertical displacements are 4.50 mm or 14.13 mm accordingly. Hence, the conclusion is that the steps taken for stabilisation and reconstruction of the landslide on the road Mavrovo - Debar meet the project-exploitation requirements.