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Experimentally testing animal responses to prescribed fire size and severity
Conservation Biology, Volume 38, Issue 3, June 2024.Abstract Deserts are often highly biodiverse and provide important habitats for many threatened species. Fire is a dominant disturbance in deserts, and prescribed burning is increasingly being used by conservation managers and Indigenous peoples to mitigate the damaging effects of climate change, invasive plants, and land‐use change. The size, severity,
Tim S. Doherty +4 more
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Research progress of support theory and technology of the roadway surrounding rock based on the plastic zone control [PDF]
With the increasing depth of coal mining, the stability control of surrounding rock in deep roadway has become one of major problems in the mining field, and the effect of surrounding rock control in deep roadway is directly related to the safe ...
Lei FAN +3 more
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Analysis of the Incipient Failure During Outburst of Coal and Gas [PDF]
, 2008 针对煤矿煤与瓦斯突出动力现象的复杂过程,对突出启动前煤体的初次破坏特征进行了分析。特别是对影响突出发生的煤体初次破坏的几何特征以及层裂拱壳形成的力学原理,通过简化的力学模型做了分析,同时讨论了影响初次破坏特性的主要因素,包括与不同煤体结构相适应的煤体材料不同破坏准则的影响。为进一步认识煤与瓦斯突出的机理,突出的启动、发展演化提供一种思路 ...
张均锋, 韩小波
core
Influence of loading system stiffness on unstable failure mode and energy evolution of sandstone under lateral constraints [PDF]
In order to explore the influence of the stiffness of the loading system on rock failure mode and energy evolution law, the self-developed rigidity and variable stiffness test system is used to carry out biaxial compression tests, and the mechanism of ...
Chongyan LIU +6 more
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Zhendong Ceshi yu Zhenduan为了研究空心板梁桥抗爆性能，在任意拉格朗日‑欧拉（arbitrary Lagrange‑Euler，简称ALE）多物质流固耦合理论基础上，使用LS‑DYNA软件对空心板梁桥爆炸问题进行求解分析。通过模拟试验梁爆炸来验证模拟方法的准确性，从不同TNT当量、横截面上不同典型爆点部位和不同爆点区域等方面对空心板梁桥的损伤过程、压力场和动力响应进行参数化分析，以研究空心板梁桥的破坏模式和损伤情况。结果表明：爆炸冲击波进入空心板梁的空心室后，会在空心室内聚集，超压峰值因约束效应而增大，空心板底部很薄则很容易被击穿，
doaj +1 more source
Jianzhu Gangjiegou Jinzhan, 2020 为了获悉苏州太平金融高层格构式树形柱的轴压性能和破坏机理,对格构式树形柱缩尺试件展开了轴压试验研究。试验结果表明,格构式树形柱的轴压受力性能良好,试件破坏主要集中在分肢柱弯头处。利用ABAQUS有限元软件建立了格构式树形柱的数值分析模型,通过破坏模式和荷载-位移曲线验证了有限元分析模型的准确性。针对格构式树形柱在较大轴压荷载作用下分肢柱弯头处破坏的情况,提出了提高十字拉结梁高度、设置纵向隔板、填充混凝土等3种构造加强措施,并通过有限元分析验证了其改善效果。研究表明 ...
王静峰 +4 more
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Jianzhu Gangjiegou Jinzhan, 2021 设计了复式钢管混凝土钢梁半穿心加肋加腋型节点,制作了4个梁柱试件组合体进行低周往复加载试验,并采用ABAQUS有限元软件建立了节点数值分析模型。半穿心节点刚度较大,破坏模式主要为梁端塑性铰破坏,节点试件的滞回曲线呈明显的纺锤形,耗能性能较好,有限元分析结果与试验结果吻合较好。利用有限元模型研究了节点构造、几何参数和材料参数对半穿心节点的破坏模式和承载力的影响。参数分析表明:梁柱线刚度比及轴压比对节点初始刚度影响显著;轴压比和钢梁强度对节点极限承载力影响较大;而节点的变形能力受轴压比影响较大 ...
张玉芬 +3 more
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Gaoya dianqi, 2022 特高压直流旁路开关是换流站中的关键设备，为评估某±800 kV特高压旁路开关的抗震性能，文中建立了旁路开关设备的有限元模型，并对其进行了动力特性和地震响应分析，确定设备抗震薄弱位置和关键响应，采用对数正态分布拟合旁路开关不同损伤状态下的易损性曲线。结果表明，旁路开关设备存在两处薄弱点，即支柱绝缘子根部、旁路开关顶部，相应的破坏模式分别为支柱绝缘子根部强度破坏与旁路开关顶部牵拉破坏。PGA大于0.2g时，旁路开关主要破坏模式为绝缘子根部破坏。支架对旁路开关地震响应有显著的放大作用 ...
汤培森, 薛志航, 谢强
doaj
Mechanical properties and permeability characteristics of mudstone-slag-based water barrier material [PDF]
To investigate the influence of mudstone content and curing age on the mechanical properties and permeability characteristics of mudstone-slag-based water barrier materials, using waste sandstone from open pit coal mine stripping was used as aggregate ...
Jiangsen ZHU +6 more
core +1 more source
Jianzhu Gangjiegou Jinzhan, 2020 对武汉天河机场T3航站楼屋盖结构中2个典型内置横向插板加强空间相贯节点的受力性能进行了足尺破坏试验和有限元模拟研究,分析了两节点的破坏模式和应力变形发展过程,试验和有限元结果表明:2个试验节点均具有较高的安全储备,其破坏模式均为受压支管根部局部屈曲破坏。有限元软件可以较好地模拟节点的加载过程,两节点中插板的存在可提高其极限承载力,但对各自主管应力状态的影响不同,JD2试件中插板可有效改善其主管的应力集中现象,JD1试件中插板对其主管应力状态的影响较小。
郭杰 +5 more
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