Results 71 to 80 of about 745 (139)
Zhongguo youzhi为获得温度影响下的粮食力学参数，为粮仓相关设计提供参考，对现有粮食静动直剪仪进行改进，增设了保温剪切盒及智能温控系统，并利用该设备在大豆含水率8.99%~15.12%、孔隙率36%、温度25~45 ℃、竖向应力50~200 kPa、剪切速率2.4 mm/min、剪切位移幅值20 mm条件下开展了一系列大豆籽粒群的温控单调剪切试验，测定不同温度条件下大豆籽粒群的抗剪强度及体积剪切变形参数。结果表明：大豆籽粒群内摩擦角范围为37.1°~44.6°，咬合应力范围为9.6~21.2 kPa ...
曾长女，王少华，谷贺 ZENG Changnyu, WANG Shaohua, GU He
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Analysis on factors controlling shallow failures of the cut slopes and its prevention by bio-engineering measures: A case study of the cut slopes along the highway from Shuangcheng to Dajiali [PDF]
Understanding the primary and secondary relations of influencing factors is crucial for predicting deformation and controlling collapse in cutting slopes. Using a cutting slope along the Shuangcheng to Dalijia expressway in Gansu Province as the research
Changgen YAN +4 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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Zhendong Ceshi yu Zhenduan为提高综掘装备用短距摆动式刮板输送机的运行可靠性，首先，基于悬链线理论建立刮板链张紧补偿位移与链节间张力的理论模型，推导出刮板链在输送槽弯道区域的摩擦阻力、链节间张力以及侧向挤压力的理论计算方法，构建短距摆动式刮板输送机刚柔耦合多体接触动力学模型；其次，结合输送机尾横摆现场试验，利用压力⁃速度数据，调试设定刚柔耦合仿真模拟试验参数；最后，提出在不同横摆角度、输送机仰角和刮板链链速多种工况条件下短距摆动式掘进刮板输送机周期循环动态张力分布获取方法，探究空载摆动工况周期闭环运行下刮板链⁃弹簧板 ...
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Macro-meso mechanical properties of gas hydrate bearing coal under triaxial compression with flexible boundary condition [PDF]
To explore the influence of confining pressure on the macro-meso mechanical characteristics of gas hydrate bearing coal (GHBC) under different boundary conditions, the biaxial discrete element tests were carried out subjected to the confining pressures ...
Baoyong ZHANG +5 more
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Shuitu Baochi Xuebao[目的] 合理施用秸秆和有机肥能有效改良土壤,对土壤酸度和抗侵蚀能力产生积极作用。[方法] 以酸化红壤为研究对象,对比常规施肥(CK),化肥减量(30%)和秸秆还田(6 000 kg/hm2,FSM0),及化肥减量(30%)加上秸秆还田(6 000 kg/hm2)和配施不同梯度有机肥(1 500,3 000,4 500,6 000 kg/hm2)(FSM1、FSM2、FSM3、FSM4)对油菜生长各阶段土壤性质和产量的影响。[结果] 化肥减量配施秸秆和有机肥显著改善土壤酸度和养分状况(p＜0.05 ...
申梦雪 +9 more
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Strength criterion and verification of transversely isotropic unsaturated loess based on spatial sliding surface variation [PDF]
In order to scientifically predict the strength and deformation characteristics of large-area fill foundations, a comprehensive and systematic study is conducted on mechanical properties of transversely isotropic unsaturated remolded loess through ...
GUO Nan1 , YANG Xiaohui1, JIA Shining1, CHEN Zhenghan1, 2
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Gaoya dianqiGIS中的断路器电动拒分是运行中较为普遍的缺陷，为明确故障成因，以发生电动拒分现象的某型号操动机构为对象展开研究。在故障操动机构返厂后的解体试验中，对包括保持挚子在内的分合闸关键部位零部件，采用外观检查、尺寸测量、硬度测试等技术手段，从运行环境、材料性能和传动工况等方面进行了多角度分析讨论，并建立高精度有限元模型进行仿真验证。发现发生故障的操动机构，其主拐臂装配内孔均有一侧存在加工误差，且热处理后硬度偏离设计要求。结果表明：主拐臂两侧装配内孔非对称，使得内置滚针轴承和销轴产生轴线微偏心；在受力状态下 ...
孙庆峰 +5 more
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Analysis of stability and kinematics of the dangerous rock mass in Zhangjiagou, Baoxing, Sichuan Province [PDF]
After the “6 • 1” Lushan earthquake, unstable rock mass was discovered in Zhangjiagou, posing a severe threat to the safety of the residents and their property below.
Bo ZHONG +5 more
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Shuitu Baochi Xuebao, 2017 ：以重庆市城镇建设活动形成的典型工程堆积体为研究对象，对工程堆积体边坡物理力学特性和入渗特征进行了研究，同时确定工程堆积体边坡的危险滑动面及安全系数。在工程堆积体边坡上、中、下设置采样点，采集土壤样品进行土壤物理力学性质分析，采用野外双环入渗法进行入渗过程研究，运用GEO-SLOPE软件分析工程堆积体边坡稳定性。结果表明：（1）工程堆积体粒度分布不均匀，且中坡位>下坡位。（2）工程堆积体饱和含水量随坡位下降呈逐渐增加趋势；入渗率随时间变化呈快速减小、缓慢减小、稳定入渗3个阶段，2 m、2 a和4 ...
丁文斌 +3 more
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