Journal of Arid Land  2022, Vol. 14 Issue (6): 604-619    DOI: 10.1007/s40333-022-0019-7
 Research article
Sheltering effect of punched steel plate sand fences for controlling blown sand hazards along the Golmud-Korla Railway: Field observation and numerical simulation studies
ZHANG Kai1,2,*(), TIAN Jianjin1, QU Jianjun2, ZHAO Liming1, LI Sheng1
1College of Civil Engineering, Lanzhou Jiaotong University, Lanzhou 730000, China
2Key Laboratory of Desert and Desertification, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China

Abstract

Sand fences made of punched steel plate (PSP) have recently been applied to control wind-blown sand in desertified and Gobi areas due to their strong wind resistance and convenient in situ construction. However, few studies have assessed the protective effect of PSP sand fences, especially through field observations. This study analyzes the effects of double-row PSP sand fences on wind and sand resistance using field observations and a computational fluid dynamics (CFD) numerical simulation. The results of field observations showed that the average windproof efficiencies of the first-row and second-row sand fences were 79.8% and 70.8%, respectively. Moreover, the average windproof efficiencies of the numerical simulation behind the first-row and second-row sand fences were 89.8% and 81.1%, respectively. The sand-resistance efficiency of the double-row PSP sand fences was 65.4%. Sand deposition occurred close to the first-row sand fence; however, there was relatively little sand on the leeward side of the second-row sand fence. The length of sand accumulation near PSP sand fences obtained by numerical simulation was basically consistent with that through field observations, indicating that field observations combined with numerical simulation can provide insight into the complex wind-blown sand field over PSP sand fences. This study indicates that the protection efficiency of the double-row PSP sand fences is sufficient for effective control of sand hazards associated with extremely strong wind in the Gobi areas. The output of this work is expected to improve the future application of PSP sand fences.

Received: 09 March 2022      Published: 30 June 2022
Corresponding Authors: ZHANG Kai     E-mail: zhangkai0212@yeah.net
 Fig. 1 Aeolian environment of study area. (a), annual sand-driving wind rose; (b), monthly frequency of sand-driving wind; (c), annual drift potential. DP, drift potential; RDP, resultant drift potential; VU, vector units; RDD, resultant drift direction. Fig. 2 Field observation made on double-row PSP sand fences. (a), cross-section diagram of the anemometers; (b), cross-section diagram of the sand traps. PSP, punched steel plate, H, the height of the sand fence, which is 2 m. Fig. 3 Schematic diagram of the model of computational domain and boundary conditions. H, the height of the sand fence, which is 2 m. Fig. 4 Simulated mesh and the mesh near the hole of sand fence Table 1 Calculated local order accuracy (p) and fine-grid convergence indices ($GCI_{21}^{^{\text{fine}}}$) for horizontal velocities Fig. 5 Inlet, approach, and incident flows in empty computational domains. (a), vertical profiles of the turbulent kinetic energy (k); (b), vertical profiles of the specific dissipation rate (ω); (c), vertical profiles of the absolute pressure (p); (d), vertical profiles of the mean wind velocity (u). Fig. 6 Wind velocity variation around double-row sand fences. X/H is the ratio of the distance in the X direction to H; and VX/VH is ratio of the velocity in the X direction to the velocity of the fence height H. Fig. 7 (a), sand flux density around the double-row PSP sand fences for a wind velocity of 10.3 m/s; (b), variation of sand flux density along the sand-control system; (c), variation of sand-resistance efficiency along the sand-control system. X/H is the ratio of the distance in the X direction to H. Fig. 8 (a), Overall diagram of the flow field distribution of the double-row PSP sand fences (Z/H is the ratio of the distance along the Z direction to H); (b), normalized diagram of horizontal velocity distribution diagram of double-row PSP sand fences; (c), horizontal velocity distribution diagram of the double-row PSP sand fences; (d), windproof efficiency of double-row PSP sand fences. X/H is the ratio of the distance in the X direction to H. Fig. 9 Deposition and erosion around the fence. X/H is the ratio of the distance in the X direction to H. τ, surface shear stress by wind flow; τt, ground shear force. Fig. 10 Double-row PSP sand fences on study area. (a), first-row sand fence; (b), second-row sand fence.