摘要
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。
The sand hazards is mainly depended on co operation of the factors of dynamical system-wind power and echo system-ground surface state. Along the Desert Highway the types of aeolian geomorphology are complex and various, and rich in sand supplies. The sand driving wind has high frequencies and durative action. So the sand controlling has sheer difficulty. The 'prevention stabilization' system which combined with the upright reed sand blocking fences and 1m×1m semicovered reed checkerboard barriere has being set controlling the sand hazards effectively. But some problems exist still. The results of survey of fixed site show that along Desert Highways the direction of effective wind and sand transport are fasten on NE,ENE,E. They account for 46%-68% of the total. Theoretically on the windward side's (east side of the road lines) protecting intensity should be strengthened, but in fact, strong wind erosion and sand deposition inner the stabilizing belts made the relationships of effective duration and its width indistict. Hence, the principle of narrow width and maintain frequent should be adopt, the width on the windward side controlls within 30-40m, resets every 3-4 years and maintains in time. The leeward side may not set upright fence, the width of stabilizing belts is suitable to be controllde within 10-15m. The width of blank belt between upright fence and the semi covered checkerboard fence is suitable to be controlled within 8H. Accounting to degree of sand hazards, using sole reed fixed fence, the mobility fence of double sandbag block and combined fixed fence with mobility fence will strengthen sand protecting intensity at the fore edge. By using technics such as setting different standard and height of semi covered checkerboard fence in different location, solid slope of road shoulder and creating sand transporting section ets, and forming the solid control system, sand hazards could be controlled sufficiently.
出处
《干旱区资源与环境》
CSSCI
CSCD
2000年第2期35-40,共6页
Journal of Arid Land Resources and Environment
基金
国家"八五"科技攻关项目!( 85 -10 1-0 7-0 2 )获国家科技进步一等奖
关键词
沙漠公路
沙害
防沙体系
防护宽度
沙障
Desert highway. Sand hazards. Sand controlling system. Protection width. Mobility fence. Fixed fence.
