磷尾矿对玄武岩纤维加筋膨胀土工程特性影响研究

Study on Influence of Phosphorus Tailings on Engineering Characteristics of Basalt Fiber Reinforced Expansive Soil

为改善膨胀土工程特性,满足路基填料使用要求,分别研究了玄武岩纤维加筋膨胀土胀缩特性和磷尾矿改良加筋膨胀土力学强度变化规律。研究结果表明:玄武岩纤维可有效改善膨胀土胀缩特性,每增加0.1%纤维掺量,加筋膨胀土膨胀率约下降5.3%~8.6%,当玄武岩纤维掺量为0.3%时,加筋膨胀土膨胀力达到最小值;采用磷尾矿改良0.3%玄武岩掺量的膨胀土,12%磷尾矿掺量对加筋膨胀土力学强度改良效果显著,抗压强度达到峰值。通过室内试验结果,建议改良膨胀土玄武岩纤维和磷尾矿掺量分别为0.3%、12%。

In order to improve the engineering characteristics of expansive soil and meet the requirements of subgrade filling, the expansion and contraction characteristics of basalt fiber reinforced expansive soil and the mechanical strength of modified reinforced expansive soil of phosphorus tailings were studied. The test results show that the basalt fiber can effectively improve the expansion and contraction characteristics of the expansive soil. For each 0.1% fiber content increase, the expansion rate of the expansive soil decreases by about 5.3%~8.6%. When the basalt fiber content is 0.3%, reinforced expansive soil expansion force reaches a minimum;the expansive soil with 0.3% basalt content modified by phosphorus tailings, the 12% phosphorus tailings dosage has significant effect on the mechanical strength improvement of the reinforced expansive soil. Through the indoor test results, it is suggested that the modified expansive soil basalt fiber and phosphorus tailings content are 0.3% and 12%, respectively.