Introduction. Geosynthetic materials in the form of rigid geogrids of various structures and raw material composition are widely used in modern road construction technologies to reinforce the granular layers of the basics of road pavement, which ensures their durability and reliability.
Problem statement. When arranging the basis of the road bases made of granular materials (gravel, gravel — sand mixtures, etc.), due to the penetration of individual particles into the lower sandy layers or mixing with the soil and there is a loss of material and on the surface of the road structure excessive deformation and destruction in the form of deposits are possible. The reinforcement of the granular layers by geogrids, due to wedging of the particles in the cells of grid, provides a synergistic effect by including in the work of the reinforcing material its stretching and the operation of the layer as a plate, which is not present in the original granular layer. Given the specificity and emergence of new materials, there is a need to develop new test methods and evaluate the quality of geosynthetics with different cell shape.
Purpose. The purpose of this study is to develop a method for determining the characteristics of rigid geogrids with different cell shape, for used to reinforce the granular layers of road pavement.
Materials and methods. Typical geogrids of the same raw material composition with different shape of the cells (square and triangular), which are used as reinforcing material in the arrangement of granular layers of road pavement of roads, were selected for the study.
Results. The article presents the experimental data of the grid deformation dependence ∆l, mm, after application of a given load P, kN. A technique for determining the strength and deformability of rigid geogrids of various shapes has been developed.
For hexagonal geogrids, the most advantageous is a statically defined diagram in the form of two triangles connected by a hinge (statically defined diagram).
For structures working in the conditions of flat stress-deformed state (embankments, slopes, retaining walls, etc.), more effective are two-axis geogrids.
Conclusions. In Ukraine, there is no methodology for assessing the physico-mechanical characteristics of geogrids of a three-axis structure. The article describes the method of characterization and compares rigid geogrids with different cell shape, which are intended for reinforcing the granular layers of the basis of road pavement. It is necessary to develop a normative document for testing rigid geogrids for reinforcing grainy layers of road pavement of roads.
