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沙害主要取决于两个系统因素的共同作用 :动力系统—风力和响应系统—下垫面状况。塔里木沙漠公路沿线风沙地貌形态类型复杂多样 ,沙源充足 ;起沙风频数高 ,作用时间长 ,防沙难度极大。已建成的高立式芦苇阻沙栅栏和 1 m× 1 m半隐蔽芦苇草方格固沙沙障结合的“阻固”体系 ,有效控制了沙害 ,但也存在一定问题。定位观测表明 ,沿线起沙风和输沙方向集中于 NE、ENE、E三个方向 ,占 46%～ 68% ,从理论上说 ,应加大风侧 (路东侧 )防护力度 ,而实际上固沙带内部强烈的风蚀与沙埋过程 ,使其有效年限与设置宽度关系不明显 ,宜采取窄宽度勤维修原则 ,上风侧宽度控制在 3 0 m～ 40 m,每 3～ 4年更新一次并及时维修。下风侧可不设置高立式沙障 ,固沙带宽度控制在 1 0 m～ 1 5 m为宜 ;高立式沙障与半隐蔽方格沙障前沿之间空留宽度控制在 8H以内较为适宜。依沙害程度 ,以单一原状芦苇固定沙障、复膜沙袋阻沙体活动沙障及固定沙障与活动沙障有机结合加强前沿阻沙力度 ;不同沙害部位设置不同规格不同高度的半隐蔽方格沙障、固化路肩边坡创造输沙断面等技术 ,形成立体防护体系 ,足以控制沙害。
Sand damage depends mainly on the synergy of two system factors: the power system - the wind and the response system - the underlying surface condition. The sandstorm morphological types along the Tarim Desert Highway are complex and diversified, and the source of sand is abundant. The frequency of the sandstorm is high, the action time is long, and the prevention of sand is extremely difficult. The completed “barrier” system of high vertical reed sand blocking fence and 1 m × 1 m semi-concealed reed grass combined with square grid sand barrier can effectively control sand damage, but there are also some problems. Positioning observations show that the direction of sandstorm and sand transport along the route are concentrated in the three directions of NE, ENE and E, accounting for 46% -68%. Theoretically speaking, the intensity of protection on the windward side (the east side of the road) should be increased. In fact, The strong wind erosion and sandblasting process inside the sand-fixing belt makes the relationship between its effective life and setting width not obvious. The principle of narrow width maintenance should be adopted. The width of the windward side should be controlled from 30 m to 40 m and be updated every 3 to 4 years Timely maintenance. It is not necessary to set up a vertical sand barrier on the leeward side, and the width of the sand control belt should be controlled between 10 m and 15 m. It is appropriate to control the empty width between the high vertical sand barrier and the semi-concealed grid sand barrier within 8H. According to the degree of sands harm, the sand barrier of single reed fixation, the sand barrier of sandblasting with sandbag and the combination of fixed sand barrier and active sand barrier can be used to strengthen the frontal sand resistance; the sand cover with different specifications and different height Grid sand barrier, solidified shoulder slope to create sections such as sand transport technology, the formation of three-dimensional protective system, enough to control sand damage.