岩石力学与工程学报
巖石力學與工程學報
암석역학여공정학보
CHINESE JOURNAL OF ROCK MECHANICS AND ENGINEERING
2013年
9期
1813-1819
,共7页
孔祥辉%蒋关鲁%邹祖银%李安洪
孔祥輝%蔣關魯%鄒祖銀%李安洪
공상휘%장관로%추조은%리안홍
岩石力学%红层泥岩%循环荷载%临界动应力%累积变形%路用性能
巖石力學%紅層泥巖%循環荷載%臨界動應力%纍積變形%路用性能
암석역학%홍층니암%순배하재%림계동응력%루적변형%로용성능
rock mechanics%red mudstone%cyclic loading%critical dynamic stress%accumulative deformation%pavement performance
为验证达成(达州--成都)线红层泥岩能否满足高速铁路路基填料的要求,对其进行室内动三轴试验和红层泥岩路基的现场循环加载试验。由动三轴试验研究红层泥岩在循环荷载下的动强度和变形特性,引入动应力水平的概念,得到达成线红层泥岩的临界动应力水平约为30%;通过分析动剪应力比SR d与土体累积变形之间的关系,提出一个红层泥岩循环累积变形的计算模型,并明确模型参数的物理意义及确定方法。现场循环加载试验表明,用红层泥岩填筑路基基床底层,路基的沉降量和沉降速率均能满足高速铁路的要求;应用所提出的预测模型来计算红层泥岩路基层的累积变形,其达到稳定时的计算值和实测值很接近,但由于现场和室内试验条件的不同及加载频率的影响,在变形稳定以前,模型计算值和实测结果之间存在一定的差异。
為驗證達成(達州--成都)線紅層泥巖能否滿足高速鐵路路基填料的要求,對其進行室內動三軸試驗和紅層泥巖路基的現場循環加載試驗。由動三軸試驗研究紅層泥巖在循環荷載下的動彊度和變形特性,引入動應力水平的概唸,得到達成線紅層泥巖的臨界動應力水平約為30%;通過分析動剪應力比SR d與土體纍積變形之間的關繫,提齣一箇紅層泥巖循環纍積變形的計算模型,併明確模型參數的物理意義及確定方法。現場循環加載試驗錶明,用紅層泥巖填築路基基床底層,路基的沉降量和沉降速率均能滿足高速鐵路的要求;應用所提齣的預測模型來計算紅層泥巖路基層的纍積變形,其達到穩定時的計算值和實測值很接近,但由于現場和室內試驗條件的不同及加載頻率的影響,在變形穩定以前,模型計算值和實測結果之間存在一定的差異。
위험증체성(체주--성도)선홍층니암능부만족고속철로로기전료적요구,대기진행실내동삼축시험화홍층니암로기적현장순배가재시험。유동삼축시험연구홍층니암재순배하재하적동강도화변형특성,인입동응력수평적개념,득도체성선홍층니암적림계동응력수평약위30%;통과분석동전응력비SR d여토체루적변형지간적관계,제출일개홍층니암순배루적변형적계산모형,병명학모형삼수적물리의의급학정방법。현장순배가재시험표명,용홍층니암전축로기기상저층,로기적침강량화침강속솔균능만족고속철로적요구;응용소제출적예측모형래계산홍층니암로기층적루적변형,기체도은정시적계산치화실측치흔접근,단유우현장화실내시험조건적불동급가재빈솔적영향,재변형은정이전,모형계산치화실측결과지간존재일정적차이。
In order to verify the applicability of red mudstone as subgrade filling in Dazhou-Chengdu railway, laboratory dynamic triaxial tests and field cyclic loading tests were performed. The dynamic strength and deformation properties of red mudstone were investigated by the dynamic triaxial tests. After introducing the concept of dynamic stress level,the test results indicate that the critical level of dynamic stress is about 30%. By analyzing the correlation between dynamic shear stress ratio and accumulative deformation,this paper proposes a calculation model of accumulative deformation of red mudstone subjected to cyclic loads,and presents the physical meaning and determining method of model parameters. The results of field cyclic loading tests demonstrate that settlement and rate of subsidence of subgrade can meet the requirements of high-speed railway construction when using red mudstone to fill the base layer of subgrade bed. Employing the proposed prediction model to calculate the accumulative deformation of red mudstone layer,the calculated and measured values match well as the deformation is stable;but some differences are observed before deformation stability due to different conditions and loading frequencies between laboratory and field tests.