Uso de geossintéticos como reforço em estradas não pavimentadas

Abstract

Brazil faces serious problems for the marketing of your products, which ultimately contributing to waste and increase costs on the final product. The main routes for the flow of Brazilian agricultural production are the roads. However, observes that great extension of the road network is composed of unpaved roads, because its implementation is fast and its cost is low. Many unpaved roads crossing places where the soil has a low bearing capacity load, which can cause excessive surface deformations and rainy periods are formed puddles often leaving the road impassable. In this context, a study conducted with the objective to find a solution quickly and effectively when the subgrade is fully saturated. Were selected three points on unpaved roads to submit low load-bearing capacity. Withdrew soil samples from each point and led to the laboratory. The study was conducted to determine the depth of installation of the geosynthetic analyzing the load-bearing capacity (CBR) of the system (saturated subgrade-reinforcing base) by was in randomized blocks with a 4x3 factorial, with four types of geosynthetic ( GT, GNT, GG and SG) and 3 of geosynthetic installation depths (0.09 m, 0.06 m e 0.03 m) with two replicates. With the ideal depth molded samples with saturated subgrade and traffic simulator utilized a laboratory to simulate the road traffic, permanent deformation (rutting) was measured by means of photography for 2, 8, 20, 36, 60 and 100 in the past situations with and without reinforcement. Conducted the study through regression equations and set the has calculated number of passes for the same amount of permanent deformation permitting calculation of the traffic benefit ratio provided by the inclusion of the reinforcement. With the study concludes that the present work shows the technical feasibility of using traffic simulator to reproduce the actual situation considering the scale effect. The best result was obtained to road three, reaching the reasons benefit of traffic - TBR average of 2.71 for the geotextile woven and 2.23 for the geotextile non-woven geotextile, while for other situations averaged TBR = 1.43. The CBR test is not performed effectively to simulate the effect of including strengthening the conditions evaluated, because the CBR does not have conditions to anchor the geosynthetic, so it is not suitable to test the use of reinforcements in soils. It was found that reinforcement is more effective for large displacements of the embankment thus to roads with low flow of vehicle (small trafficability) and small deformations the effectiveness of reinforcement is lower. And the deformations are decreasing with increasing past.