The preparation of a straw engineering sand-fixing plank and its sand-fixing and replanting performance exploration

Abstract

To improve the shortcoming of sand fixation in traditional engineering, the study prepares a kind of porous composite for sand fixation and replanting by taking waste straw as the skeleton, polyvinyl alcohol and aquasorb as the composite agent, then pressing moulding by a press machine. Firstly, the effect of PVA on the mechanical properties is studied by sheering strength. In addition, the fracture mechanism of the composite is analysed by infrared spectrum of the PVA and photos under the optical microscope. Then, it is studied the influence of the amount of aquasorb on the water absorption and retention ability of the composite through the water absorption ratio and water content. Besides, the good water retention and replanting performance of aquasorb is visualized through the macro humidity contrast. The results show that, with the increase of PVA content, its sheering strength first decreases and then increases to the peak value, which is as high as 4.79MPa. It can be seen through the analysis of fracture morphology, that the composite crosslinking of PVA and aquasorb forms a three-dimensional network structure. And the structure enhances the toughness of the composite. With the increase of the content of the aquasorb, the water absorption ratio and the water content first increase and then decrease. When the content is 33.33%, the effect reaches to the optimal level, the water absorption ratio reaches to 3.76 and the repeated water absorption ratio reaches to 2.71. What’s more, the water content is always higher than other proportions. Therefore, the composite can effectively cooperate with plants and extend the years of sand control. The study provides a new idea and basis for the combination of sand fixation and waste straw.