岩土力学
巖土力學
암토역학
Rock and Soil Mechanics
2015年
11期
3180-3186
,共7页
松散堆积体%边坡%降雨%离心模型%PIV
鬆散堆積體%邊坡%降雨%離心模型%PIV
송산퇴적체%변파%강우%리심모형%PIV
deposit%slope%rainfall%geotechnical centrifugal model%PIV
采用新型介质雾化喷嘴离心场降雨模拟设备,进行了模拟降雨及格栅支护措施条件下松散堆积体边坡的离心模型对比试验。离心机模型与原型试验比尺为1:80,试验过程通过非接触定点高速摄影系统并结合粒子图像测速(particle image velocimetry)技术分析了试验过程中边坡的位移场变化。试验结果表明,松散堆积体边坡在未降雨条件下是十分稳定的;在进行模拟降雨后,边坡顶部沉降及坡面水平位移随降雨量的增大逐渐发展,尤其边坡表面区域发生明显变形;边坡的破坏模式有别于传统的圆弧滑动,在持续强降雨作用下,坡面逐层产生破坏,最终形成泥石流形态;通过采取坡面土工防护格栅支护条件后,堆积体边坡在降雨条件下稳定性显著提高,故采用边坡防护格栅是提高松散堆积体边坡稳定性的有效途径。
採用新型介質霧化噴嘴離心場降雨模擬設備,進行瞭模擬降雨及格柵支護措施條件下鬆散堆積體邊坡的離心模型對比試驗。離心機模型與原型試驗比呎為1:80,試驗過程通過非接觸定點高速攝影繫統併結閤粒子圖像測速(particle image velocimetry)技術分析瞭試驗過程中邊坡的位移場變化。試驗結果錶明,鬆散堆積體邊坡在未降雨條件下是十分穩定的;在進行模擬降雨後,邊坡頂部沉降及坡麵水平位移隨降雨量的增大逐漸髮展,尤其邊坡錶麵區域髮生明顯變形;邊坡的破壞模式有彆于傳統的圓弧滑動,在持續彊降雨作用下,坡麵逐層產生破壞,最終形成泥石流形態;通過採取坡麵土工防護格柵支護條件後,堆積體邊坡在降雨條件下穩定性顯著提高,故採用邊坡防護格柵是提高鬆散堆積體邊坡穩定性的有效途徑。
채용신형개질무화분취리심장강우모의설비,진행료모의강우급격책지호조시조건하송산퇴적체변파적리심모형대비시험。리심궤모형여원형시험비척위1:80,시험과정통과비접촉정점고속섭영계통병결합입자도상측속(particle image velocimetry)기술분석료시험과정중변파적위이장변화。시험결과표명,송산퇴적체변파재미강우조건하시십분은정적;재진행모의강우후,변파정부침강급파면수평위이수강우량적증대축점발전,우기변파표면구역발생명현변형;변파적파배모식유별우전통적원호활동,재지속강강우작용하,파면축층산생파배,최종형성니석류형태;통과채취파면토공방호격책지호조건후,퇴적체변파재강우조건하은정성현저제고,고채용변파방호격책시제고송산퇴적체변파은정성적유효도경。
In this study, a new media atomizing nozzle was adopted by rainfall simulation equipment for centrifugal model tests. Three comparative tests were conducted to simulate the behaviors of the deposits slope under the conditions of the rainfall and grid support. The scale of the centrifuge model to prototype was selected as 1:80. The displacement field of deposits slope was measured by a high-speed flash photography system, which had characteristics of non-contact and fixed-spot and was combined with program of particle image velocimetry (PIV). It was found that deposits slope was very stable without rainfall, but with increasing rainfall time, the settlement at top of slope and the horizontal displacement at surface of slope were both enlarged. Particularly, obvious deformation was observed on the surface of slope. Under continuous intensive rainfall, the slope failure mode was different from the traditional circular slide, since the slope failed layer by layer until a‘debris flow’ was generated. However, the stability of the slope was significantly enhanced once protective geogrids were applied. Thus the application of geogrid supports efficiently improve the slope stability under rainfall conditions.