Deformationand Strength Characteristics Of Glass Fiber-Reinforced Soil Studied By Experiments

Currently there are few researches on mixing the glass fiber into soil body as reinforced materials at home and abroad. Besides outstanding physical and chemical properties, the glass fiber also has numerous other merits, such as relatively low price and considerable producibility. Therefore, the study on the engineering characteristic and reinforcement mechanism of the glass fiber-reinforced soil is of engineering significance.The compression characteristic of the glass fiber-reinforced soil was studied through the consolidation test of glass fiber-reinforced soil. The stress-strain relationship, strength and deformation characteristics of the glass fiber-reinforced soil were studied through the triaxial compression test of glass fiber-reinforced soil. The tensile property of glass fiber- reinforced soil was studied through the tension test of glass fiber -reinforced clay .The principal factors which influence on the strength of glass fiber-reinforced soil were firstly comprehensively analyzed. The strength of glass fiber-reinforced soil was then quantitatively analyzed. And finally the empirical equation of strength indexes was deduced. The result showed that:1. Both the fiber length and the fiber mixing ratio could affect on the compressibility of glass fiber-reinforced soil. With the increase of fiber length and the fiber mixing ratio, the compressibility modulus of the glass fiber-reinforced soil becomes higher while the compression index becomes smaller. At the same time, the curve line of e-logp tends towards stability and the compressibility of the glass fiber-reinforced soil decreases. When the fiber length or fiber mixing ratio reaches a certain level, the e-log p curve is in shape of approximately a straight line.2. The stress-stain relationship of the glass fiber-reinforced soil is approximately manifested by hardening characteristic. The destructional forms of both materials mentioned above are swelling destruction. The cohesion of soil could be increased significantly through the mixing of glass fiber. However, it doesn't have appreciable effect on the internal frictional angle.3. There is nonlinear relationship between the cohesion which is the strength index and the fiber length as well as the mixing ratio of glass fiber-reinforced soil. The empirical equation of intensity indexes was deduced on the basis of tests. With the increase of the fiber length and the mixing ratio, the increasing degree of shearing strength becomes higher. Furthermore, there is nonlinear relationship between the increasing degree of shearing strength and the mixing ratio while the increasing degree of shearing is linear to the fiber length.4. The fiber could improve the tensile strength of kaolin. When the mixing ratio increases from 0 to 1‰, the increasing degree of tensile strength is comparatively higher. When the mixing ratio is larger than 1‰, the increasing degree of tensile strength is linear to the mixing ratio.And the increasing degree of tensile strength is nonlinear to the fiber length. With the increase of the fiber length, the tensile strength increases bigger in the first stage and smaller in the later stage.5. With the increasement of the fiber length and content, the reinforcement effect coefficient of glass fiber-reinforced sand and glass fiber-reinforced clay nonlinear improves largely. The reinforceing effect of glass fiber-reinforced clay is better than that of fiber-reinforced sand with the shorter length of fiber (i.e.5cm) . Compared to reinforcement clay, the mixing ratio of reinforcing effect is increased with the increase of fiber length, but the amplitudes is diminished.6. The reinforcement effect subjected to tensile loading is better than that of compression loading. With the length and mixing ratio of fiber increasing, the amplitudes of reinforcement effect become smaller. The reinforcement effect coefficient of the two kinds of tests is connected with the nonlinear relationship between the length and different dosages used of glass fiber.