{"title":"Experimental investigation and modelling of the mechanical behaviors of fine/coarse soil mixture","authors":"","doi":"10.1016/j.trgeo.2024.101382","DOIUrl":null,"url":null,"abstract":"<div><div>An interlayer was formed in the conventional railway track, due to the interpenetration between ballast grains and subgrade fines under the effect of train circulation. Considering the interlayer’s high bearing capacity, it has been remained in the railway track in its renewal program. In present study, the mechanical behaviors of such fine/coarse soil mixture were experimentally explored and theoretically modeled. Results show that: (i) the soil–water retention curve (SWRC) of mixture was solely related to the dry density of fine soil <em>ρ</em><sub>d-f</sub>, while independent of the coarse grain content <em>f</em><sub>v</sub>; (ii) two various fabrics of mixture were distinguished by a characteristic <em>f</em><sub>v-cha</sub> value: a fine matrix macrostructure when <em>f</em><sub>v</sub> < <em>f</em><sub>v-cha</sub> and a coarse grain dominated fabric when <em>f</em><sub>v</sub> > <em>f</em><sub>v-cha</sub>; (iii) an increasing water content induced the growth of permanent strain <span><math><msubsup><mi>ε</mi><mrow><mn>1</mn></mrow><mi>p</mi></msubsup></math></span> and a decline of resilient modulus <em>M</em><sub>r</sub> due to the decline of suction <span><math><mi>ψ</mi></math></span>, but the growth of damping ratio <em>D</em><sub>r</sub> due to the rise of soil viscosity; (iv) a constitutive model was developed for the <span><math><msubsup><mi>ε</mi><mrow><mn>1</mn></mrow><mi>p</mi></msubsup></math></span> by incorporating the SWRC, which allows the influences of the number of loading cycles <em>N</em>, deviator stress <em>σ</em><sub>d</sub> and <em>f</em><sub>v</sub> to be considered. A constitutive model was also proposed for the <em>M</em><sub>r</sub>, taking the influences of <em>σ</em><sub>d</sub>,<span><math><mi>ψ</mi></math></span> and <em>f</em><sub>v</sub> into account.</div></div>","PeriodicalId":56013,"journal":{"name":"Transportation Geotechnics","volume":null,"pages":null},"PeriodicalIF":4.9000,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Transportation Geotechnics","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2214391224002034","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, CIVIL","Score":null,"Total":0}
引用次数: 0
Abstract
An interlayer was formed in the conventional railway track, due to the interpenetration between ballast grains and subgrade fines under the effect of train circulation. Considering the interlayer’s high bearing capacity, it has been remained in the railway track in its renewal program. In present study, the mechanical behaviors of such fine/coarse soil mixture were experimentally explored and theoretically modeled. Results show that: (i) the soil–water retention curve (SWRC) of mixture was solely related to the dry density of fine soil ρd-f, while independent of the coarse grain content fv; (ii) two various fabrics of mixture were distinguished by a characteristic fv-cha value: a fine matrix macrostructure when fv < fv-cha and a coarse grain dominated fabric when fv > fv-cha; (iii) an increasing water content induced the growth of permanent strain and a decline of resilient modulus Mr due to the decline of suction , but the growth of damping ratio Dr due to the rise of soil viscosity; (iv) a constitutive model was developed for the by incorporating the SWRC, which allows the influences of the number of loading cycles N, deviator stress σd and fv to be considered. A constitutive model was also proposed for the Mr, taking the influences of σd, and fv into account.
期刊介绍:
Transportation Geotechnics is a journal dedicated to publishing high-quality, theoretical, and applied papers that cover all facets of geotechnics for transportation infrastructure such as roads, highways, railways, underground railways, airfields, and waterways. The journal places a special emphasis on case studies that present original work relevant to the sustainable construction of transportation infrastructure. The scope of topics it addresses includes the geotechnical properties of geomaterials for sustainable and rational design and construction, the behavior of compacted and stabilized geomaterials, the use of geosynthetics and reinforcement in constructed layers and interlayers, ground improvement and slope stability for transportation infrastructures, compaction technology and management, maintenance technology, the impact of climate, embankments for highways and high-speed trains, transition zones, dredging, underwater geotechnics for infrastructure purposes, and the modeling of multi-layered structures and supporting ground under dynamic and repeated loads.