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Mechanical properties and deformation damage characteristics of deep rock under unloading and compensation paths [PDF]
To study the effect of stress compensation on the mechanical properties and deformation damage characteristics of unloading sandstone, a true triaxial perturbation unloading rock testing system was used to carry out unloading experiments on sandstone ...
Chongyan LIU +4 more
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Shuitu Baochi Xuebao, 2021 为了系统性研究灌木植物根系的固土力学效应，探讨土体对根系的摩阻特性，以4种不同土壤粒径（原级配，1.0~2.0，0.5~1.0，
郭欢 +4 more
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Experimental study on mechanical properties of rock degraded by hydraulic fracturing [PDF]
The accurate determination of the degree of mechanical property degradation of rock layers after hydraulic fracturing is the basis for revealing the pressure relief mechanism of hydraulic fracturing and evaluating the fracturing effect.
Junfeng PAN +5 more
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Shuitu Baochi Xuebao, 2022 为探究等高反坡阶整地改良红壤坡耕地土壤质量的效果, 利用田间定位试验, 以滇中昆明松华坝迤者流域坡耕地试验区已实施等高反坡阶整地措施3(CRT 3), 7(CRT 7), 9(CRT 9)年的样地及原状坡耕地(CK)为研究对象, 结合各样地玉米产量探明实施年限对土壤结构、肥力和酶活性特征的影响。结果表明: 等高反坡阶整地年限显著改善坡耕地土壤的物理性状, 呈现黏粒、粉粒、总团聚体和总孔隙度显著增加, 砂粒和容重显著降低; 提高了土壤肥力, 其中全氮、全磷、全钾、速效磷、速效钾含量和含水量显著提高 ...
刘晓微 +5 more
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Calculation of passive earth pressures on retaining wall considering soil arching effects of backfill clayey soil [PDF]
, 2014 为解释挡土墙后填土被动土压力的非线性分布现象,在考虑土拱形状为圆弧,滑裂面采用朗肯滑裂面的基础上,给出考虑土拱效应的被动土压力系数kAWn,进而基于应力状态法及土楔形体静力平衡两种思想求解了竖向平均应力V？公式,在该基础上,给出黏性土填料下的挡土墙被动土压力分布公式、合力公式及作用点高度计算公式。通过与试验与其他方法对比,文中提出的方法得到验证。最后,研究了黏性土填料下的挡土墙被动土压力变化规律,即考虑土拱效应求得的黏性土填料的被动土压力分布呈现上小下大的指数型分布。此外,随着δ/φ(δ为墙土摩擦角 ...
刘德稳 +4 more
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Duncan-Chang Constitutive Model of Vetiver Root and Soil Matrix at Different Growth Stages [PDF]
[Objective] To investigate the constitutive relationship governing the entire failure process of root-soil matrixs. [Methods] By employing the Duncan-Chang model and conducting triaxial tests, a stress-strain constitutive relationship model was developed
JI Jinnan, WU Ruibin, YANG Yuzhe
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Zhendong Ceshi yu Zhenduan为进一步加强Hertz软球碰撞模型中刚性颗粒与弹塑性材料碰撞的相关研究，利用弹塑性半平面接触本构关系，引入一种新的阻尼形式，建立了硬球颗粒‑聚氨酯平面的黏弹塑性碰撞模型，并推导出颗粒与弹塑性平面碰撞的非线性动力学方程。首先，通过测定球形煤精颗粒碰撞聚氨酯恢复系数实验，确定了所用聚氨酯材料的Meyer指数与动力学方程中的阻尼系数；其次，在方程中考虑不同的阻尼形式，对比证明了所提阻尼模型的正确性；然后，分析了不同阻尼系数下，不同阶段接触力的变化机理；最后，探讨了颗粒与弹塑性聚氨酯碰撞过程中位移 ...
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Experimental study on seismic performance of composite reinforced structure with shock absorption and energy dissipation of potentially collapsedrock mass [PDF]
At present, there are two types of structures for strengthening dangerous rock mass in earthquake area construction: anchorage and retaining. The connection between the two types of reinforced structures and the dangerous rock mass is rigid with very ...
Aishe ZHANG +5 more
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Shuitu Baochi Xuebao目的为揭示土壤各粒级团聚体组分理化性质及其对镉（Cd）赋存形态的影响机制，研究典型水稻土团聚体分布特征及不同粒径团聚体对Cd环境行为的影响。方法选取Cd污染水稻土麻砂泥田（花岗岩发育）与鳝泥田（板页岩发育），通过湿筛法将土壤团聚体分为4个粒级：大团聚体（2~8 mm）、中间团聚体（0.25~2 mm）、微团聚体（0.053~0.25 mm）和粉黏粒（<0.053 mm），分析不同粒径团聚体去除有机质与游离态氧化铁对Cd的吸附作用。结果2种土壤均以大团聚体为主，鳝泥田团聚体结构较麻砂泥田稳定 ...
贺汝婧 +7 more
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Deformation and fracture characteristics of rock under creep-impact loading based on subcritical crack growth [PDF]
During deep resources extraction, deep rock is subjected to high stress and dynamic disturbances, leading to frequent dynamic disasters such as coal rock bursts that severely restrict the safe and efficient production of deep resources.
Guangchao ZHANG +7 more
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