Mechanical properties analysis of palm fiber reinforced quartz sand
[Background]Sandy soil is more likely to cause soil erosion and stratum deformation because of its loose structure,easy liquefaction,easy erosion and other defects.In recent years,fiber reinforcement technology has been widely used in road and slope protection projects because of its ability to improve soil structure and enhance the mechanical properties of soil as a whole.However,when synthetic fibers are used as reinforcing materials to strengthen the soil,the characteristics of synthetic fibers,such as difficult to degrade and easy to cause environmental pollution,make it difficult to be widely promoted in actual projects.Therefore,this paper investigates the effect of mixing natural palm fiber into quartz sand to simulate the effect of plant fiber reinforcement technology on sandy soil,which is of great significance for analyzing the soil and water conservation effect of plant fiber reinforcement technology.[Methods]Triaxial drained compression tests were carried out on saturated palm fiber reinforced quartz sand.The deviator-strain curve,stress path and volume change under different reinforcement conditions were obtained.According to the test results,the coefficient of enhanced strength of fiber reinforced sand,shear strength and void ratio of the compressed sample were analyzed with the fiber content and fiber length.[Results]1)The peak deviator stress and residual strength of the reinforced sand sample are higher than that of plain sand samples.The maximum coefficient of enhanced strength is 1.39,while the maximum residual strength of the fiber reinforced sand can reach 2.2 times of plain sand.The fiber mainly strengthens the residual strength of the quartz sand.Therefore,the strain softening behavior of pure sand changes into strain hardening performance of fiber reinforced sand,which has more ability to resist the deformation.2)It shows that the shear strength of sand samples generally increases with the fiber content,as well as generally increases with fiber length.The shear strength is the highest when the fiber length is 20 mm and the fiber content is 0.9％.3)The volumes of fiber reinforced sand have a similar trend as the pure sand,but they can reach higher values and keep increasing rather than converging at a stable value.Compared with pure sand,the axial strain of fiber reinforced sand changes greatly when reaching the critical porosity,and the dilatancy rate of the specimen reduces,which proves that palm fibers help sand samples enhance the ability to resist greater strains.[Conclusions]The interfacial stress between palm fiber and quartz sand particles improves the mechanical properties of quartz sand,and the results provide a test basis for the application of plant fiber reinforcement technology in sand fixing engineering.
palm fiberquartz sandmechanical propertiesfiber reinforcedresidual strengthporosity ratio
万方数据
维普
