STUDY ON CHANGE OF ELASTIC SHEAR MODULUS BY CYCLIC LOADING AND ITS MECHANISM OF BASE COURSE MATERIAL

路盤材料の繰返し載荷時のせん断剛性変化とそのメカニズムに関する研究

There is a possibility that the ballasted track occurs in the ballasted track of rail way. However, little is known about change of the elastic shear modulus by cyclic loading and its mechanism of the base course material. In this study, mechanism of change of the elastic shear modulus by cyclic loading and wetting-induced collapse behavior were evaluated by mean of cyclic traxial loading test, bender element test and X-ray CT scan. The test results show that although the volume strain was increased by cyclic loading, the collapse settlement was not observed. In the case of small void ratio, the trend of increasing elastic shear modulus by the cyclic loading can be evaluated by the coordination number from X-ray CT scan. 鉄道における有道床軌道では路盤陥没が発生する場合がある.しかし,路盤材料に対する繰返し載荷前後での剛性変化や飽和度上昇時の沈下特性に関する実験データは少ない.そこで本研究では,実際の道路で使用されている路盤材料に対し,繰返しおよび浸水三軸試験,ベンダーエレメント試験およびX線CTスキャンを行い,浸水時の沈下特性および繰返し載荷に伴うせん断剛性率の変化とそのメカニズムについて検討した.その結果,繰返し載荷に伴い体積ひずみは増大するものの,浸水時の体積圧縮は確認できなかった.また,繰返し載荷に伴うせん断剛性率の増加は,間隙比変化のみでは説明できず,配位数の増加傾向と符合することが明らかとなった.

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  • Accession Number: 01600073
  • Record Type: Publication
  • Source Agency: Japan Science and Technology Agency (JST)
  • Files: TRIS, JSTAGE
  • Created Date: Mar 23 2016 3:04PM