This study introduces the tubular braided structure as a new geosynthetic material for sand reinforcement. The performance of a tubular braid under the influence of similar soil–reinforcement interaction mechanisms has been investigated to emphasize the effect of the reinforcement form on the performance of the reinforced soil composite. For this purpose, three series of interaction element tests including direct shear tests, pull-out tests, and soil stress control tests were conducted on the unreinforced and reinforced sand. Finally, the overall performance of the reinforced foundation bed with the planar and tubular reinforcing textile (with similar materials, properties, texture, and areal density) was evaluated through a series of standard plate load tests. The results indicated that the performance of the sand-braid composite was better compared to the similar typical planar reinforcement, except for the case of pull-out test. Tubular braid resulted in the enhanced shear strength of the reinforced soil composites, mobilization of the excess compressive stress in the enclosed soil inside the tubular braids, reduction in the vertical stress level of the footing model transferred down through the soil bed, the increase of the average bearing capacity of the footing model, and a significant reduction in the footing settlement.

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In the present era, due to various industrial developments, there is a need to use different applications of nuclear energy. But the leading challenge is the management of nuclear waste, which emits dangerous rays such as gamma rays. This research aim is to create a layer to be used as a protective coating against radiation in low-level waste landfills. In this paper, bentonite is used as a base material and red mud as an additive. Also, to determine the linear attenuation coefficient (µ), a combination of bentonite with 0, 15, 30, and 45% red mud with bentonite was used. To perform a linear attenuation coefficient test, the NaI (Tl) detector and the source of Co 60 were used at two energy levels of 1173 and 1332 keV. The results of laboratory tests show that the addition of red mud has improved the parameter of the linear attenuation coefficient of radiation at both energy levels so that the energy level of 1173 keV and 1332 keV with the addition of 45% red mud has improved by 16 and 12%, respectively.