Shear Strength Enhancement of Cemented Reinforced Sand: Role of Cement Content on the Macro-Mechanical Behavior

Sands reinforced by hydraulic binders (cement) have constituted in recent decades a major asset for the expansion of several areas of engineering. The mechanical behavior of sand-cement mixtures has undergone some controversies studied on the Chlef sand. In this paper, we present an experimental study to investigate the mechanical behavior of a sandy soil reinforced by a hydraulic binder (cement), using the direct shear apparatus emphasizing on the shear strength characteristics and the vertical deformation variation of cemented reinforced sand. The parameters used in this study are mainly: relative density (Dr = 80%), normal stress (σn = 100, 200, 400 kPa), water content (3, 7 and 10%), cement content (2.5, 5, 7.5 and 10 %) and cure time (7, 14 and 28 days). The experimental results show that the mechanical characteristics in terms of internal cohesion (C) and internal frication angle (φ) give a better mechanical performance with the binder inclusion, and the cure conditions play an effective role on the improvement of the shear strength. This result also showed that 10% of the cement content gave us a maximum value of shear strength and an optimal influence on the mechanical characteristics. The addition of cement not only improves the shear strength of soil, but also provides diversity in the resistance against the deformations imposed load, which can be established by a dilatant character

Effect of dynamics on the Soil-geosynthetic interfaces used in reinforced rockfall embankments

International audienceAmong the various passive protection structures, embankments reinforced with horizontal inclusions are one of those capable of containing the blocks with the highest kinetic energies, e.g. exceeding 5000 kJ (Descoeudres, 1997). The design of such structures requires consideration of parameters related to the soil-geosynthetic interfaces during the impact by the block on the embankment. In spite of recent technological developments, the response of soil-geosynthetic interfaces under dynamic loading of impact type remains largely unknown. This issue is tentatively addressed based on a numerical study of the dynamic pull-out behaviour of a geotextile sheet embedded into soil, as in rockfall protection embankments

Shear Strength Enhancement of Cemented Reinforced Sand: Role of Cement Content on the Macro-Mechanical Behavior

Sands reinforced by hydraulic binders (cement) have constituted in recent decades a major asset for the expansion of several areas of engineering. The mechanical behavior of sand-cement mixtures has undergone some controversies studied on the Chlef sand. In this paper, we present an experimental study to investigate the mechanical behavior of a sandy soil reinforced by a hydraulic binder (cement), using the direct shear apparatus emphasizing on the shear strength characteristics and the vertical deformation variation of cemented reinforced sand. The parameters used in this study are mainly: relative density (Dr = 80%), normal stress (σn = 100, 200, 400 kPa), water content (3, 7 and 10%), cement content (2.5, 5, 7.5 and 10 %) and cure time (7, 14 and 28 days). The experimental results show that the mechanical characteristics in terms of internal cohesion (C) and internal frication angle (φ) give a better mechanical performance with the binder inclusion, and the cure conditions play an effective role on the improvement of the shear strength. This result also showed that 10% of the cement content gave us a maximum value of shear strength and an optimal influence on the mechanical characteristics. The addition of cement not only improves the shear strength of soil, but also provides diversity in the resistance against the deformations imposed load, which can be established by a dilatant character

Shear Strength Enhancement of Cemented Reinforced Sand: Role of Cement Content on the Macro-Mechanical Behavior

Sands reinforced by hydraulic binders (cement) have constituted in recent decades a major asset for the expansion of several areas of engineering. The mechanical behavior of sand-cement mixtures has undergone some controversies studied on the Chlef sand. In this paper, we present an experimental study to investigate the mechanical behavior of a sandy soil reinforced by a hydraulic binder (cement), using the direct shear apparatus emphasizing on the shear strength characteristics and the vertical deformation variation of cemented reinforced sand. The parameters used in this study are mainly: relative density (Dr = 80%), normal stress (σn = 100, 200, 400 kPa), water content (3, 7 and 10%), cement content (2.5, 5, 7.5 and 10 %) and cure time (7, 14 and 28 days). The experimental results show that the mechanical characteristics in terms of internal cohesion (C) and internal frication angle (φ) give a better mechanical performance with the binder inclusion, and the cure conditions play an effective role on the improvement of the shear strength. This result also showed that 10% of the cement content gave us a maximum value of shear strength and an optimal influence on the mechanical characteristics. The addition of cement not only improves the shear strength of soil, but also provides diversity in the resistance against the deformations imposed load, which can be established by a dilatant character

Laboratory Study on Shear Strength Behaviour of Reinforced Sandy Soil: Effect of Glass-Fibre Content and Other Parameters

International audienc

Shear Strength Response of a Geotextile-Reinforced Chlef Sand: A Laboratory Study

International audienc

Mechanical Behavior of Sand Mixed with Rubber Aggregates

The main objective of this study is to compare the mechanical behavior of two sands (Hostun or Dune sands) mixed with crushed rubber obtained from used tires. However, it is essential to ensure that his geotechnical application do not result in long-term negative impacts on the environment. The chemical properties of these two sands are given by energy dispersive analysis X-ray fluorescence spectrometry. The mineral composition of these two sands is performed by X-ray diffractometry. The morphological characteristics of the sand grains are given by the analysis of the images of the two sands given by the scanning electron microscope. This study is based on 120 direct shear tests performed on sand-rubber aggregate mixtures. The results show that the rubber content of the aggregates has a significant effect on the shear strength of sand-rubber mixtures in both cases of sand. In fact, the shear strength of the sand-rubber mixture increases with increasing crushed rubber up to 20% for different normal stresses. The analysis of the test results also shows the effect of the angular shape of the sand grains on the interparticle friction. The contribution of the structure effect in the mobilized friction is analyzed by comparing the shear test results of Hostun and dune sand mixtures