Results 81 to 90 of about 3,060 (161)
Jianzhu Gangjiegou Jinzhan, 2008 按照《钢结构设计规范》（GB 50017-2003）计算组合梁考虑滑移后的折算刚度时,会遇到栓钉数量增加,刚度反而下降的现象。本文提出了新的折算刚度表达式,引入了钢与混凝土的组合作用系数来表征钢和混凝土轴压刚度通过抗剪件的作用而形成的组合作用的程度,采用考虑滑移影响的组合梁计算理论,求出了均布荷载下简支梁挠度的表达式,得到精度很高的简化计算公式,考察了栓钉抗滑移刚度值的确定方法,通过简单的分析,本文提出了折减刚度的计算公式,并与试验结果对比。将本文公式与规范计算公式和试验结果的对比,建议公式的误差更小 ...
童根树, 夏骏
doaj
Prediction of water inflow after excavation of underground chamber group with long span and high buried depth [PDF]
Predict the water inflow after excavation of large underground caverns is crucial for the safe construction and operation of underground engineering. To predict the water inflow of underground caverns after excavation and provide guidance for drainage ...
Guanghong JU +5 more
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Failure depths of stope floors under dynamic loading induced by roof breaking [PDF]
ObjectiveAccurately assessing the failure depths of stope floors is crucial for assessing floor water inrush risks. Conventional theoretical models for calculating the failure depths generally merely consider static loads from the support pressure and ...
Bo XU +5 more
core +1 more source
Zhendong Ceshi yu Zhenduan为研究管道过流产生的流激振动对穿管堤防稳定性的影响，以广东省某穿管堤防为例，首先，建立管道‑堤防三维有限元模型，依据渗流计算确定最不利穿管工况，得到穿管堤防最大渗透力；其次，根据实测振动响应反演流激振动荷载，结合有限元动力法与强度折减法进行边坡动力稳定性分析；最后，采用间接耦合法实现渗透力‑流激振动多荷载耦合，研究渗流与流激振动对边坡稳定性的影响。结果表明：在仅考虑渗流作用下，穿管堤防上、中、下3种穿管工况安全系数分别降低15.0%、5.4%和16.5%；在渗透力‑流激振动耦合作用下 ...
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Shuitu Baochi Xuebao, 2020 以康定县折多山高寒山地灌丛草甸凋落物为研究对象，采用室外调查及室内测定结合的方法分析了凋落物蓄积量、持水及失水过程，以期探讨不同海拔和坡向凋落物水源涵养功能的差异。结果表明：（1）研究区凋落物的蓄积量在4.02~4.77 t/hm2波动，均表现出随着海拔的升高而逐渐降低，且半阴坡>半阳坡，海拔对凋落物蓄积量呈极显著影响（P0.95，P0.99 ...
吕宸 +6 more
doaj
Pressure distribution and fluid migration law of gas lift reverse circulation well washing flow field in drilling sinking [PDF]
In order to reveal the pressure distribution and fluid migration law of the gas lift reverse circulation washing flow field in drilling method, the ø5m advanced drilling of the north wind well in Taohutu coal mine was taken as the research background ...
Chuanxin RONG +5 more
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Jianzhu Gangjiegou Jinzhan, 2009 本文用斜拉杆简化模型分析了钢板墙从弹性屈曲到拉力带全部屈服的受力全过程。考虑了真实的拉力带倾角、塑性变形系数和屈服后阶段弹模折减等因素影响,用斜拉杆模型模拟了拉力带的受力过程,推导了斜拉杆初始屈服应力、极限应力、钢板墙剪力和位移计算公式,得到了钢板墙的弹塑性荷载-位移曲线,最后与试验资料比较验证了公式的有效性。
曹春华, 郝际平, 王迎春, 李峰
doaj
CFDEM simulation on the linkage effect between floor faults failure and roof collapse in ultra-thick coal seam [PDF]
The ultra-thick coal seam has a large mining space and a wide range of overburden disturbance. The strong disturbance of loading and unloading caused by the roof collapse can easily exacerbate the failure of floor faults.
Dong YANG +4 more
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Jacking resistance in collapsed body considering buckling of force chain [PDF]
In order to establish an effective and secure emergency rescue channel within a collapsed structure using the pipe jacking method, understanding the evolution mechanism of jacking resistance is crucial.
Chuanbo HAO +5 more
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Thought of full-stratigraphy and its practice in ground control [PDF]
Ground control is a science of mitigating or eliminating mining damage by controlling the breaking motion of mining rock strata, with the aim of ensuring safe, efficient and green mining.
Changchun HE +13 more
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