Zhang Xiangdong, Pang Shuai, Li Jun, Zhang Xuefeng, Cai Guanjun, Tian Lijun
School of Civil Engineering, Liaoning Technical University, Fuxin 123000, China.
Beijing Jingneng Geo-Engineering Ltd., Beijing 102300, China.
Materials (Basel). 2022 Apr 13;15(8):2860. doi: 10.3390/ma15082860.
Experimental studies on reinforcing aeolian sand with cement and fiber are lacking, and the interface mechanism and splitting characteristics thus remain unclear. Herein, the interface mechanism and splitting characteristics of fiber-reinforced, cement-solidified, aeolian sand were experimentally assessed to investigate whether glass fiber exhibits better properties as a reinforcing agent than traditional fiber-free cement-solidified aeolian sand, and whether aeolian sand is applicable as a base material in geotechnical engineering. The splitting experiments involved the use of fiber-reinforced, cement-solidified aeolian sand samples that were differentiated based on the mixing schemes used to formulate them. Based on the strengthening control technology effects on the structural performance of the fiber-reinforced, cement aeolian, sand-mixed matrix material, the internal physical and chemical mechanisms of structural performance evolution were revealed and analyzed using scanning electron microscopy images. The experimental results show that the splitting strength of the sample reaches its maximum value at a combination of 6 mm glass fiber, 3‱ fiber, and 10% cement contents. In fiber-reinforced cement-solidified aeolian sand, cement hydrate forms more needle-shaped crystal products. The crystals adhere to the fiber surfaces that interweave with each other to form a porous and dense network. Although this improves the bonding force between the fiber and aeolian sand particles, the fibers are prone to fracture and slippage during the splitting process. The three-dimensional network structure formed by overlapping fibers is critical for the improvement of the splitting strength. The study's findings will serve as benchmarks to achieve additional improvements in glass fiber-reinforced cement-solidified aeolian sand.
关于用水泥和纤维加固风积沙的实验研究较少，因此界面机理和劈裂特性仍不明确。在此，对纤维增强、水泥固化风积沙的界面机理和劈裂特性进行了实验评估，以研究玻璃纤维作为增强剂是否比传统的无纤维水泥固化风积沙具有更好的性能，以及风积沙是否适用于岩土工程中的基础材料。劈裂实验使用了根据配制时的混合方案区分的纤维增强、水泥固化风积沙样品。基于增强控制技术对纤维增强水泥风积沙混合基体材料结构性能的影响，利用扫描电子显微镜图像揭示并分析了结构性能演变的内部物理和化学机理。实验结果表明，在玻璃纤维6mm、纤维掺量3‱和水泥含量10%的组合下，样品的劈裂强度达到最大值。在纤维增强水泥固化风积沙中，水泥水化物形成更多针状晶体产物。这些晶体附着在相互交织的纤维表面，形成一个多孔且致密的网络。虽然这提高了纤维与风积沙颗粒之间的粘结力，但在劈裂过程中纤维容易断裂和滑动。由重叠纤维形成的三维网络结构对于提高劈裂强度至关重要。该研究结果将作为进一步改进玻璃纤维增强水泥固化风积沙的基准。
