CAJ | 학술논문

为了解新型材料生物可降解聚乳酸纤维( PLA)沙障防风效益,通过测定PLA沙障样地内不同高度风速,分别研究1m×1m、2m×2m、3m×3m规格PLA沙障防风效能、地表粗糙度与风速廓线特征,同时以相同坡位同种规格的传统半隐蔽式麦草沙障样地和流动沙丘为对照,对比研究了PLA沙障与传统麦草沙障的防风效益。结果表明,新型生物可降解PLA沙障防风效能显著大于麦草沙障,2种类型沙障最大差值可达10.3%,2种材料沙障不同规格防护效果为1 m×1 m规格较其他2种规格更好；2种材料沙障增加地表粗糙度表现为PLA沙障>麦草沙障>流动沙丘,且均随规格增大呈逐渐下降趋势,在相同地形条件下,PLA沙障地表粗糙度均值为麦草沙障的1.4倍；2种材料沙障在迎风坡坡底、坡中、坡顶及背风坡4种地形下地表粗糙度差异不明显,其地表粗糙度均值为0.7 cm；1m×1m规格的PLA方格沙障和麦草沙障内的风速廓线曲线呈现“S”型曲线特征,而在2m×2m和3m×3m规格的2种材料沙障内,风速廓线与对照裸沙丘相似,其风速廓线均呈指数函数分布。随着沙障规格的增大,降低风速作用减弱,其风速廓线逐渐由“S”型趋向于指数函数曲线。
위료해신형재료생물가강해취유산섬유( PLA)사장방풍효익,통과측정PLA사장양지내불동고도풍속,분별연구1m×1m、2m×2m、3m×3m규격PLA사장방풍효능、지표조조도여풍속곽선특정,동시이상동파위동충규격적전통반은폐식맥초사장양지화류동사구위대조,대비연구료PLA사장여전통맥초사장적방풍효익。결과표명,신형생물가강해PLA사장방풍효능현저대우맥초사장,2충류형사장최대차치가체10.3%,2충재료사장불동규격방호효과위1 m×1 m규격교기타2충규격경호；2충재료사장증가지표조조도표현위PLA사장>맥초사장>류동사구,차균수규격증대정축점하강추세,재상동지형조건하,PLA사장지표조조도균치위맥초사장적1.4배；2충재료사장재영풍파파저、파중、파정급배풍파4충지형하지표조조도차이불명현,기지표조조도균치위0.7 cm；1m×1m규격적PLA방격사장화맥초사장내적풍속곽선곡선정현“S”형곡선특정,이재2m×2m화3m×3m규격적2충재료사장내,풍속곽선여대조라사구상사,기풍속곽선균정지수함수분포。수착사장규격적증대,강저풍속작용감약,기풍속곽선축점유“S”형추향우지수함수곡선。
To understand the windproof benefit of new biodegradable PLA sand barrier, we studied respectively the windproof efficiency, roughness of ground surface and wind speed profile characteristics of 1 mí1 m, 2 mí2 m, 3 mí3 m PLA sand barriers by measuring the wind speeds in different heights in PLA sand barrier sample plots. At the same time we took the traditional half hidden straw sand barrier sample plots and shifting dunes as contrast, and studied the difference of windproof efficiency between PLA and straw sand barrier. The results showed that wind speed efficiency could be reduced by PLA sand barrier more significantly than straw sand barrier with the biggest difference 10.3%, the windproof efficiency with 1 mí1 m was better than other two for both PLA and straw sand barriers. Increasing the surface roughness ranked in PLA sand barrier > straw sand barrier > shifting dune. With the increasing of sand barrier size, the surface roughness showed the decreasing trend. Under the same terrain condition, the average surface roughness in PLA sand barrier sample plots was 1.4 times of that in straw sand barrier. The differences of surface roughness in PLA sand barrier and straw sand barrier on the bottom of upwind slope, mesoslope, slope top and leeward slope were not obvious with its average surface roughness 0.7 cm. The wind speed profile for both 1 mí1 m PLA sand barrier and straw sand barrier appeared as“S”type, while sand barriers of other sizes were as similar as shifting dunes with wind speed profile of exponential distribution. Comparing three sizes sand barriers by both two different materials, the effect of decreasing wind speed became less with the size increase, and the “S” characteristic of wind speed profile was less and less obvious until close to exponential distribution.