为揭示机械沙障抗拉力学特性,优选合适的阻沙固沙材料,利用TY8000系列伺服控制机对试验对象进行纵向拉伸试验。结果表明：当孔隙度为均一型（全疏型或全密型）时,不同材料沙障的试样宽度与抗拉力均呈幂函数正相关,与抗拉强度呈幂函数负相关,其抗拉力与伸长量变化曲线均为单峰曲线;当材料相同时,不同孔隙度沙障的试样宽度与抗拉力均呈幂函数正相关,与抗拉强度呈幂函数负相关,其抗拉力与伸长量变化曲线类型不同,即均一型沙障的抗拉力均为单峰曲线,而混合型（上疏下密型）沙障则为双峰曲线;当试样宽度大于4 cm时,上疏下密伸长量>全密型伸长量>全疏型伸长量,其大小分别为(141.23±2.56)、(103.46±3.20)mm和(63.50±1.20)mm;在测定过程中,试样宽度大的实测值小于试样宽度小的实测值,由于实际过程中局部丝网受力不均所致,出现了“颈缩”现象。建议在野外布设时多使用上疏下密型沙障,并根据当地的实际风况,首先应对沙障材料进行室内抗拉力学特性的预实验,避免由经验化引起的铺设问题,以达到防风固沙效益的最大化。

Suitable sand-resisting and sand-fixing materials were selected in order to reveal the tensile properties of mechanical sand barriers. We used the TY8000 series servo controller to conduct longitudinal tensile evaluation on the test objects. Our results indicated that when the porosity is uniform (full-sparse or full-dense), the width of sand barriers made up of different materials is positively correlated with the power function, whereas the tensile strength is negatively correlated with the power function. When the material is the same, the tensile strength and elongation change form unimodal curves. The width of sand barriers with different porosity and its tensile strength are positively correlated with the power function and negatively correlated with the tensile strength. The tensile forces of uniform sand barriers are unimodal, while that of mixed type (sparse upper and lower dense) sand barriers are bimodal. When the width of the sample is greater than 4 cm, the upper sparse and lower dense elongation is greater than the elongation of full dense type, followed by that of the full sparse type, with sizes of 141.23±2.56 mm (mean±standard deviation), 103.46±3.20 mm, and 63.50±1.20 mm, respectively. The values recorded for large sample width are smaller than those recorded for small sample width. The “necking” phenomenon occurs due to the local wire mesh’s uneven force during the process. We recommend using the upper sparse and lower dense sand barriers when laying in the field. Depending on the existing local wind conditions, the tensile properties of sand barrier materials should be pre-tested indoors to avoid problems due to insufficient wind protection and maximize the benefits of sand fixation.