Abstract:The compression tests were conducted on geotextile bags with sand of different sizes,different volume and different compactness to explore influences of friction,compactness and size on the compressive strength and failure mode.The calculation formula of compressive strength considering the interface friction and compactness was proposed based on the existing theoretical research results.The results indicate that the compressive strength of a single sample is greater than that of many samples,so the existing studies on the single geotextile bag with sand have some deficiencies.The compressive strength of geotextile bag with sand decreases with the increase of the compactness.The sizes have a little effect on the mechanical and deformation and have significant effects on the ultimate bearing capacity.The failure mechanism of geotextile bag with sand is different under different compactness:it quickly produces the tensile deformation and failure when the compactness is large,and failure occurs mainly in the sewing interface which is relatively weak.With the decrease of the compactness,the geotextile bags show progressive failure caused by the strain localization,which is unfavorable because the failure is uneasy to find in the practical engineering.The comparison with the test results indicates that the theoretical calculation method can be used to predict the compressive strength when the tensile failure.