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常用尼龙阻沙网的孔隙度为均匀分布,而风沙流结构在垂直方向上是非均匀分布的。通过设计4种孔隙度非均匀分布的尼龙阻沙网:大条带上疏下密式(A)、大条带上密下疏式(B)、小条带疏密相间式(C),将其布设在塔克拉玛干沙漠腹地的垄间平地,以均匀结构阻沙网为对照(CK)。对4种阻沙网前后的风速变化、防风效能、积沙形态、积沙量进行对比。结果表明:①B阻沙网有效防护距离最短,仅为6H(H为阻沙网的高度),其余3种结构有效防护距离差别不大,均为15H;在网后10H处0.15 m、0.3 m和0.5 m 3个观测高度,风速削弱程度的平均值存在明显差异,呈C>A>B>CK。②在风季后期,4种结构阻沙网前后积沙量B最小,其余3种类型差别不大。③综合考虑防风和阻沙效益,C阻沙网提供了一个较好的结构模式,防护效益最好,B阻沙网最差,A和CK阻沙网效益相差不大。研究结果为高立式沙障结构优化设计提供了参考依据。
Commonly used nylon sand barrier network for the uniform distribution of porosity, and sand flow structure in the vertical direction is unevenly distributed. Through the design of four non-uniform distribution of the porosity of the nylon sand barrier: the big strip on the sparse under the dense type (A), the big strip on the dense sparse (B), small strip of dense phase (C) It was laid in the hinterland of the Taklamakan Desert Ridge flat ground, with a uniform structure of the resistance sand as CK (CK). The wind speed change, windbreak efficiency, sediment accumulation and sediment yield of four kinds of sand blocking net were compared. The results show that: (1) the effective protective distance of B sand-blocking net is the shortest, only 6H (H is the height of the sand-blocking net); the effective protective distances of the other three structures are not much different, both are 15H; 0.15m, 0.3m And 0.5 m 3 observation heights, the average value of wind speed weakened significantly, showing C> A> B> CK. ② In the late season of windy season, the sediment yield B before and after the four kinds of structures was the smallest, while the other three types showed little difference. ③ Considering the windbreak and sand-blocking benefits, the C-resistant sandblasting network provides a better structural model with the best protection efficiency. The B-resistant sandblasting network is the worst, and the difference between the A and CK sand-blocking networks is not significant. The results provide a reference for the optimization design of tall vertical sand barrier structure.