摘要
通过定水头冲刷模拟试验,对土工织物的物理、水力学、力学参数进行了分析。研究结果表明,对于充砾或充砂的土工织物袋,冲刷会使填料中的细粒嵌入土工织物孔隙,导致织物的单位面积质量及厚度增加,等效孔径O95降低。在流速3.1～4.1 m/s条件下,充砾土工织物袋在冲刷3 h内不会引起强度的明显衰减,冲刷24 h后袋体易产生局部破坏,强度可能降低20%左右,但填料的粗骨架仍可维持袋体的整体性。而充砂土工织物袋强度及延伸率变化不大,袋体局部受损情况要好于充砾土工袋,但在冲刷10 h后织物产生不均匀变形,在模型槽末端流速为2.0 m/s的部位,未见袋体明显破损。通过对比分析冲刷前后土工袋物理、水力学、力学参数的变化,发现物理性参数难以反映冲刷对材料特性的影响,选用拉伸强度等力学性质参数作为材料抗冲刷性能的反映指标较合理。
Physical,mechnics and hydraulic properties of geotextile bags were studied in this paper by using scouring experiments.The results indicated as follows： For ecological bags with gravel or sand filler,the washout can cause the fine grain material filling into the gaps of geotextile,and thus,result in weight and thickness of unit area increase and the equivalent opening size O95 is reduced.When flow velocity is 3.1-4.1 m/s,the strength of geotextile bags with gravel filler is not obviously weakened in 3 hours,but partial damage will appear on bags and the strength is reduced by about 20% while the unity of the bags is unalterable.For ecological bags with sand filler,its strength and integrity is basically constant and partial damage is better than bags with gravel filler.However,heterogeneous deformation happens after 10-hour wash.At the terminal of the experimental flume with flow velocity 2.0 m/s,damages do not appear on the bags.By comparisons of physical,mechanics and hydraulic properties before and after the experiment,this proves that physical properties can not reflect the effect of wash on material characteristics.The mechanical properties such as tensile strength etc.are more suitable indicators to reflect the erosion-resistant characteristics of materials.
出处
《长江科学院院报》
CSCD
北大核心
2010年第11期67-70,80,共5页
Journal of Changjiang River Scientific Research Institute
关键词
冲刷试验
土工织物
物理性质
力学性质
水力学性质
scouring experiment
geotextile
physical property
mechanical property
hydraulic property
