纤维掺量对海洋砂土力学性能影响研究

Effect of Fiber Content on Mechanical Properties of Sea Sand

随机分布纤维被广泛用于各类岩土工程,然而少有文献关注剑麻纤维加固海洋砂土的力学特性.本文基于室内三轴试验研究了随机分布剑麻纤维加固海砂土的强度与模量特性.试验中制备了纤维掺量分别为0%、0.3%、0.6%、0.9%、1.2%、1.5%和1.8%的纤维加固海砂土试样,进行了围压为100 kPa、200 kPa和300 kPa的三轴压缩试验.试验结果显示:随机分布剑麻纤维加固海砂土表现出明显的应变硬化特性;随机分布剑麻纤维可以显著提高海砂土的抗剪强度;围压为100 kPa时,最优纤维掺量为1.2%,围压为200 kPa和300 kPa时,最优纤维掺量为1.8%;剑麻纤维加入对海砂土试样割线模量(E 50)影响不大,但显著影响试样的弹性模量(E 0).

Randomly distributed fibers are widely used in various geotechnical projects.However,few literatures focus on the mechanical properties of sisal fiber reinforced marine sand.In this paper,the strength and modulus properties of randomly distributed sisal fiber reinforced sea sand are studied based on indoor triaxial tests.In the experiment,fiber-reinforced sand samples with fiber content of 0%,0.3%,0.6%,0.9%,1.2%,1.5%and 1.8%are prepared,and triaxial pressures of 100 kPa,200 kPa and 300 kPa are developed.The results show that random distribution of sisal fiber reinforced sand shows obvious strain hardening characteristics,and random distribution of sisal fiber can significantly improve the shear strength of sand.When the confining pressure is 100 kPa,the optimal fiber content is 1.2%.When the confining pressure is 200 kPa and 300 kPa,the optimal fiber content is 1.8%.The addition of sisal fiber has little effect on the secant modulus(E 50)of the sand sample,but significantly affects the elastic modulus(E 0)of the sample.