岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2014年
z1期
113-120
,共8页
王军%林旭%刘飞禹%潘涛%符洪涛
王軍%林旭%劉飛禹%潘濤%符洪濤
왕군%림욱%류비우%반도%부홍도
直剪试验%筋土界面%纵横肋%土工格栅
直剪試驗%觔土界麵%縱橫肋%土工格柵
직전시험%근토계면%종횡륵%토공격책
direct shear tests%geosynthetics-soil interface%longitudinal and transverse ribs%geogrid
筋材与土体接触面的相互作用较为复杂,它是加筋土工程设计中的关键所在。为了研究筋土界面的作用机制,采用福建标准砂与玻璃纤维土工格栅进行了一系列室内大型直剪试验,较为系统地分析了格栅横肋与纵肋及格栅几何尺寸对于筋土界面强度特性的影响。试验结果表明,格栅的横肋与纵肋在界面强度中均发挥了较大的作用,两者表现为不同的作用机制,当剪切位移较小时格栅横肋的被动阻力和纵肋的摩阻力起到共同承担荷载的作用;随着剪切位移的增大,横肋的被动阻力进一步提升,纵肋发挥了较为显著的提高筋材刚度的框架作用。因此,格栅的纵横肋需要按合理比例搭配才能发挥出较大的筋土界面强度。
觔材與土體接觸麵的相互作用較為複雜,它是加觔土工程設計中的關鍵所在。為瞭研究觔土界麵的作用機製,採用福建標準砂與玻璃纖維土工格柵進行瞭一繫列室內大型直剪試驗,較為繫統地分析瞭格柵橫肋與縱肋及格柵幾何呎吋對于觔土界麵彊度特性的影響。試驗結果錶明,格柵的橫肋與縱肋在界麵彊度中均髮揮瞭較大的作用,兩者錶現為不同的作用機製,噹剪切位移較小時格柵橫肋的被動阻力和縱肋的摩阻力起到共同承擔荷載的作用;隨著剪切位移的增大,橫肋的被動阻力進一步提升,縱肋髮揮瞭較為顯著的提高觔材剛度的框架作用。因此,格柵的縱橫肋需要按閤理比例搭配纔能髮揮齣較大的觔土界麵彊度。
근재여토체접촉면적상호작용교위복잡,타시가근토공정설계중적관건소재。위료연구근토계면적작용궤제,채용복건표준사여파리섬유토공격책진행료일계렬실내대형직전시험,교위계통지분석료격책횡륵여종륵급격책궤하척촌대우근토계면강도특성적영향。시험결과표명,격책적횡륵여종륵재계면강도중균발휘료교대적작용,량자표현위불동적작용궤제,당전절위이교소시격책횡륵적피동조력화종륵적마조력기도공동승담하재적작용;수착전절위이적증대,횡륵적피동조력진일보제승,종륵발휘료교위현저적제고근재강도적광가작용。인차,격책적종횡륵수요안합리비례탑배재능발휘출교대적근토계면강도。
The interaction mechanism of geosynthetics-soil interface is complicated and also important for designing the geosynthetics reinforced structure. A series of large scale direct shear tests, using Fujian standard sand and Fiberglass geogrid, are used to investigate the influence of longitudinal and transverse ribs and aperture pattern on the interface shear behavior of soil against geosynthetics. The test results show that both the longitudinal and transverse ribs play an important role in improving the interface strength through different courses of action. The shear force of interface will be shared by passive resistance of transverse ribs and friction resistance of longitudinal ribs when shear displacement is small; while the longitudinal ribs present the role of framework to improve the geogrid stiffness with the increasing of transverse resistance due to the shear displacement increasing. Therefore, coordinate work of longitudinal and transverse ribs will help to advance the interface shear strength.