期刊：
Geotechnical and Geological Engineering,2024年42(2):1505-1518 ISSN：0960-3182
通讯作者：
Chang-Ping Wen
作者机构：
[Huan-Xia Ren; Xiang Chen] School of Civil Engineering, Changde Vocational Technical College, Changde, People’s Republic of China;[Chang-Ping Wen] School of Civil Engineering, Central South University of Forestry and Technology, Changsha, People’s Republic of China
通讯机构：
[Chang-Ping Wen] S;School of Civil Engineering, Central South University of Forestry and Technology, Changsha, People’s Republic of China
期刊：
Construction and Building Materials,2024年412:134749 ISSN：0950-0618
通讯作者：
Dong, JL
作者机构：
[Zhang, Cong; Wen, Changping; Zhang, Qishu] Cent South Univ Forestry & Technol, Sch Civil Engn, Changsha 410004, Peoples R China.;[Dong, Junli; Leng, Wuming] Cent South Univ, Sch Civil Engn, Changsha 410075, Peoples R China.;[Zhou, Zhenhua] Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn, Wuhan 430071, Peoples R China.;[Zhou, Zhenhua] Univ Chinese Acad Sci, Beijing 100049, Peoples R China.
通讯机构：
[Dong, JL ] C;Cent South Univ, Sch Civil Engn, Changsha 410075, Peoples R China.
关键词：
Prestressed subgrade;Track irregularity;Heavy-haul train;3D finite element model;Dynamic stress
摘要：
To explore the dynamic transient characteristics induced by passing heavy-haul trains in newly-developed prestressed subgrade, two three-dimensional finite element models were constructed in the time domain using ABAQUS software. These models are categorized as train-track-prestressed subgrade and train-track-unreinforced subgrade. The numerical models also incorporated the vertical track irregularity commonly found in heavy-haul railways. The investigation aims to discern the dynamic stress response differences in both types of subgrades under three distinct train axle loads. Model validation occurred through comparisons with field tests gathered from various heavy-haul railways in China, as well as analogous numerical simulation cases. The findings indicate that track irregularity results in an asymmetric distribution of dynamic stress on the subgrade surface beneath both left and right rails, aligned transversely with the subgrade centerline. Additionally, this asymmetry is notably pronounced. The peak dynamic stress on the subgrade surface beneath the rails for both subgrades increases with escalating train axle loads. However, the prestressed reinforcement structure (PRS) effectively modulates this phenomenon, with the controlling advantage intensifying as train axle load increases. The average dynamic stress level in the prestressed subgrade is marginally lower than in the unreinforced subgrade within the roadbed layer beneath rails. Furthermore, train axle loads amplify the variation level of dynamic stress in the subgrade. However, the variable coefficient of dynamic stress in the prestressed subgrade is less than in the unreinforced subgrade, suggesting that PRS contributes positively to maintaining subgrade dynamic stability. In terms of the longitudinal distribution of peak dynamic stress, both subgrades exhibit normal distribution at varying depths within the roadbed layer. Lastly, the additional dynamic stress in prestressed steel bars also rises with increasing train axle loads. Nonetheless, it remains substantially lower than the static target pre-tensile stress. Moreover, the dynamic responses of prestressed steel bars in different rows attenuate as depth increases away from the subgrade top surface. In summary, this study establishes that PRS significantly enhances the dynamic stability of railway subgrade.
期刊：
Indian Geotechnical Journal,2023年53(2):283-290 ISSN：0971-9555
通讯作者：
Chang-ping Wen
作者机构：
[Xiang Tang; Chang-ping Wen] Civil Engineering Department, School of Civil Engineering, Central South University of Forestry and Technology, Changsha, People’s Republic of China
通讯机构：
[Chang-ping Wen] C;Civil Engineering Department, School of Civil Engineering, Central South University of Forestry and Technology, Changsha, People’s Republic of China
关键词：
Double yield surfaces constitutive model;Lime-treated weathered red sandstone soil;Road engineering;Stress–strain relation;Test study
摘要：
In this work, a series of triaxial consolidated drained shear tests were used to investigate the stress–strain relationships of weathered red sandstone soil and lime-treated weathered red sandstone soil. Firstly, the triaxial consolidated drained shear test results were used to analyze the relationship between deviatoric stress
$$q$$
, axial strain
$${\varepsilon }_{1}$$
, shear strain
$${\varepsilon }_{\mathrm{s}}$$
, and volume strain
$${\varepsilon }_{\mathrm{v}}$$
. Secondly, the yield surface of the soil was divided into the volume yield surface and shear yield surface, and two yield surfaces were assumed as ellipse and parabola, respectively. The ellipse volume yield surface and the parabola shear yield surface were fitted based on
$${\varepsilon }_{\mathrm{v}}-{\varepsilon }_{1}$$
,
$$q-{\varepsilon }_{\mathrm{s}}$$
test results, respectively. Finally, based on the ellipse-parabola constitutive model, the elastoplastic constitutive equations with double yield surfaces of weathered red sandstone soil and lime-treated weathered red sandstone soil were constructed. This provides a basis for the numerical analysis of the deformation of red sandstone weathered soil and lime-treated red sandstone weathered soil.
期刊：
Geotechnical and Geological Engineering,2022年40(10):5103-5113 ISSN：0960-3182
通讯作者：
Yuan, Xiang-Qian(1213984118@qq.com)
作者机构：
[Wen, Chang-Ping; Yuan, Xiang-Qian] School of Civil Engineering, Central South University of Forestry and Technology, Changsha;410018, China;[Wen, Chang-Ping; Yuan, Xiang-Qian] 410018, China
通讯机构：
[Xiang-Qian Yuan] S;School of Civil Engineering, Central South University of Forestry and Technology, Changsha, People’s Republic of China
关键词：
Coarse-grained soil;Consolidation creep;Drying-wetting cycles;Hyperbolic model;Weathered red sandstone soil
摘要：
Due to the wet-dry cycle, the consolidation creep characteristics of the weathered red sandstone coarse-grained soil have a great influence. Firstly, through the one-dimensional consolidation creep test, the strain and consolidation time curves
$$\varepsilon { - }t$$
were obtained under the wet and dry cycles conditions, and the consolidation creep hyperbolic model of weathered red sandstone coarse-grained soil was established. Then, regression equations between initial consolidation creep rate, limit consolidation creep rate, and consolidation creep rate and the wet-dry cycle times and consolidation pressure were established, and the effect of the dry and wet effect on the consolidation creep behavior of weathered red sandstone coarse-grained soil was analyzed. Finally, the normalization equation was established, and the effects of the number of dry and wet cycles and the consolidation pressure on the consolidation creep characteristics of the rough-grained soil of weathered red sandstone were analyzed. The main conclusions are as follows: (1)The test curve that consolidation creep test curve
$$\varepsilon { - }t$$
of weathered red sandstone coarse-grained soil is approximately hyperbolic. (2)Under the action of a certain consolidation pressure, when the number of the wet and dry cycles is six as the critical point, the initial consolidation creep rate
$$\dot{\varepsilon }_{0}$$
changes differently. (3)The critical creep concept is proposed through the
$$\varepsilon { - }\lg t$$
curve, the regression equation between the consolidation creep rate and the consolidation creep and the consolidation pressure is established, and the limit consolidation creep is used as the normalization factor, and the normalization equation of the consolidation creep of the weathered red sandstone coarse-grained soil under dry and wet cycle conditions is established.
作者机构：
[文畅平; 任睆遐] School of Civil Engineering, Central South University of Forestry and Technology, Changsha;410018, China;Hunan Engineering Laboratory for Manufacturing and Application Technology of Modern Timber Structural Engineering Materials, Central South University of Forestry and Technology, Changsha;[文畅平; 任睆遐] 410018, China <&wdkj&> Hunan Engineering Laboratory for Manufacturing and Application Technology of Modern Timber Structural Engineering Materials, Central South University of Forestry and Technology, Changsha;[文畅平; 任睆遐] 410018, China
作者机构：
[邓云叶] School of Urban and Rural Construction, Shaoyang Univ., Shaoyang;422004, China;[文畅平] School of Civil Eng., Central South Univ. of Forestry and Technol., Changsha;410018, China;[邓云叶] 422004, China
作者机构：
[文畅平] School of Civil Engineering, Central South University of Forestry and Technology, Changsha;410018, China;Hunan Engineering Laboratory for Manufacturing and Application Technology of Modern Timber Structural Engineering Materials, Central South University of Forestry and Technology, Changsha;[文畅平] 410018, China <&wdkj&> Hunan Engineering Laboratory for Manufacturing and Application Technology of Modern Timber Structural Engineering Materials, Central South University of Forestry and Technology, Changsha;[文畅平] 410018, China
作者机构：
[陈永青; 文畅平; 陈宗辉; 孙政; 王解军] School of Civil Engineering, Central South University of Forestry and Technology, Changsha;410018, China;Hunan Engineering Laboratory for Manufacturing and Application Technology of Modern Timber Structural Engineering Materials, Central South University of Forestry and Technology, Changsha;[方炫强] Hunan Provincial Communications Planning, Survey & Design Institute, Changsha;[陈永青; 文畅平; 陈宗辉; 孙政; 王解军] 410018, China <&wdkj&> Hunan Engineering Laboratory for Manufacturing and Application Technology of Modern Timber Structural Engineering Materials, Central South University of Forestry and Technology, Changsha
通讯机构：
School of Civil Engineering, Central South University of Forestry and Technology, Changsha, China
通讯机构：
Hunan Engineering Laboratory for Manufacturing and Application Technology of Modern Timber Structural Engineering Materials, Central South University of Forestry and Technology, Changsha, Hunan, China
作者机构：
[文畅平] Hunan Engineering Laboratory for Manufacturing and Application Technology of Modern Timber Structure Engineering Material, Central South University of Forestry and Technology, Changsha;Hunan;410018, China;School of Civil Engineering, Central South University of Forestry and Technology, Changsha;[文畅平] Hunan
通讯机构：
Hunan Engineering Laboratory for Manufacturing and Application Technology of Modern Timber Structure Engineering Material, Central South University of Forestry and Technology, Changsha, Hunan, China
