Objective Salix sand barriers are a concealed type of sand barrier, typically deployed in a grid pattern. Manual insertion and laying involve high labor intensity. Focusing on the laying of Salix grid sand barriers, a zigzag Salix sand barrier laying pattern is proposed. The overall scheme of a Salix grid sand barrier laying device was designed, with particular emphasis on the design and analysis of its branch insertion mechanism.

Method A flexible pressure roller extrusion method was employed to insert Salix branches of varying diameters. A mechanical model of the insertion process was established, and force analysis was conducted on both the pressure roller and the Salix branches. The cause of the insertion inclination angle was analyzed: the insertion direction of the Salix is subject to fluid resistance from the sandy soil. As the insertion depth increases, the velocity of the Salix branch entering the soil decreases. The deceleration displacement was solved and used to construct a geometric relationship with the initial insertion point and the insertion depth, yielding the theoretical deflection angle of the Salix branch.

Result (1) The study found that resistance from deep soil layers (> 60 mm) is the key factor causing motion lag and increased inclination angle. (2) The variation in the insertion inclination angle primarily depends on the ratio r of the laying speed to the pressure roller rotational speed. When r ≈ 7, the post-insertion inclination angle μ of the Salix is relatively small, with μ ≤ 10°. (3) By analyzing the interaction between laying speed and roller speed, the optimal parameter control range was calculated as n = 100 ~ 200 rpm, V = 600 ~ 1500 mm/s. (4) Tests showed that at a laying speed of 1 000 mm/s and a roller speed of 140 rpm, the branch insertion success rate was 88.3%. This met the requirement of a Salix insertion angle less than 10°, and the insertion performance was relatively stable and reliable.

Conclusion The Salix grid sand barrier laying device designed in this study is suitable for flat and gently sloped terrain. Focusing on the branch insertion mechanism, its rationality was analyzed and verified. The structural design of the insertion mechanism was completed. The influence of different operating parameters on sand barrier formation quality was investigated, and optimal operating parameters were determined. This work provides a reference for the design and optimization of Salix grid sand barrier laying mechanisms.