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31.
32.
为适应装配式建筑在村镇低层住宅结构发展的需求,提出了一种装配式轻钢框架-复合轻墙结构。该结构由轻钢框架作为竖向承重体系,单排配筋再生混凝土薄墙板作为抗侧力构件与轻钢框架共同抵抗水平地震作用,再生混凝土薄墙板复合EPS保温模块和粉煤灰砌块层形成保温墙体。通过4个装配式轻钢框架-复合轻墙结构和1个轻钢空框架的低周反复荷载试验,分析了墙板分布钢筋间距和墙体构造形式(是否复合粉煤灰砌块层)对该结构抗震性能的影响。研究结果表明:轻钢框架与单排配筋再生混凝土薄墙板协同工作良好,结构具有明确的两道抗震防线,由于复合EPS保温模块和粉煤灰砌块,实现了抗震节能一体化;减小墙板分布钢筋间距和复合粉煤灰砌块层可显著提高结构承载力和延性。基于JGJ 138—2016《组合结构设计规范》及相关文献,给出了装配式轻钢框架-复合轻墙结构的受剪承载力计算式,计算结果与试验结果符合较好。 相似文献
33.
截至2020年年底,全国垃圾焚烧发电行业垃圾处理能力超60万吨/日,并网装机容量达到1533万千瓦,年焚烧处理垃圾量约为1.4亿吨.十三五期间行业发展迅猛,生活垃圾焚烧发电项目在守护城乡环境、节约土地资源等方面发挥了重要作用,已是民生兜底工程,城乡协同发展的重要基础设施.在2030年碳达峰、2060年碳中和的大背景下,行业将如何发展.文中对行业现状进行简单分析,对十四五期间行业发展趋势进行预判,并提出相关行业发展建议. 相似文献
34.
Jiuchuan Wei Fuzhu Wu Huiyong Yin Jianbin Guo Daolei Xie Lele Xiao Hongfeng Zhi Liliana Lefticariu 《Mine Water and the Environment》2017,36(1):59-66
Formation of a zone of interconnected fractures during coal mining is a key factor in mine flooding. Coal mines in western China are characterized by thick coal seams with mechanically weak overburden. In situ studies including drill core analysis, drilling fluid loss measurement, and borehole video monitoring were used at the working face 101 in Shaanxi Jinjitan coal mine to explore the maximum height of the interconnected fractures zone (IFZ). Also, tests on a scaled physical model and numerical simulation based on the drilling data were used to study the formation of the fractured zone. By considering data from other mines with similar mining conditions, a logarithmic relationship was found between the maximum height of the IFZ and the thickness of coal excavation. The maximum height of the IFZ was found to be 27 times the thickness of the excavated coal seam, which is far more than in coal mining areas in eastern China. Also, the IFZ in overlying strata of the study area was arch-shaped, not saddle-shaped, as had been observed in previous studies. 相似文献
35.
采用XRD、EPMA-EDS、ICP等分析技术对脉石英进行了矿物学分析,在常压加热条件下,采用混合酸体系对脉石英砂化学浸出,制备出高纯石英。通过单因素和多因素正交试验,优化了化学浸出工艺及其参数。对于等摩尔浓度HCl和H2SO4,HCl能更好的溶解浸出金属元素;HNO3作为氧化剂,能有效氧化浸出金属元素Fe,使有害矿物黄铁矿或赤铁矿氧化还原生成可溶性Fe(NO3)3。用优化后混合酸体系可制备出SiO2稳定达到99.9wt%的高纯石英。讨论了混合酸在常压加热条件下与矿物包裹体中金属元素的反应机理。 相似文献
37.
B. Ghosh S.K. Bandyopadhyay H.G. Lele A.K. Ghosh 《Nuclear Engineering and Design》2009,239(2):327-337
The crack opening area has been estimated by various models for leak before break analysis of nuclear reactor systems. A number of linear elastic fracture mechanics models have been employed. A model has been derived based on Forman et al. [Forman, R.G., Hickman, J.C., Shivakumar, V., 1985. Stress intensity factors for circumferential through cracks in hollow cylinders subjected to combined tension and bending loads. Eng. Frac. Mech. 21, 563-571] model for stress intensity factors. The linear elastic fracture models entail the use of plasticity corrections. The convergence behaviour of the iterative implementation for plasticity correction has been studied. An elasto-plastic fracture mechanics model has also been adopted for comparative study undertaken here. The range of applicability of the models has been reviewed. 相似文献
38.
Lele Jiang Zhizhang Chen Junfa Mao 《Microwave and Wireless Components Letters, IEEE》2007,17(7):471-473
In this letter, the stability issue of the recently proposed 3-D precise integration time-domain (PITD) method is reinvestigated. It is found that the PITD is not unconditionally stable; its stability condition is strongly dependent on the preselected number of sub time-steps and sizes of numerical cells as well as the order of the approximation used. However, since the upper limit of time step is found to be proportional to the number of sub time-steps, the time step can be of a value much larger than the Courant-Friedrich-Levy limit of the conventional finite difference time domain. Numerical examples are presented to verify our analysis. 相似文献
39.
40.
The influence of incident beam divergence on the length of the streak intercepted by the Ewald sphere is considered, as a relpHK·L of a faulted hexagonal crystal, mounted about itsc-axis on the goniometer head attached to the ø-circle, is brought into diffracting condition for the bisecting setting of a 4-circle diffractometer. For the special crystal mounting correction factors required to convert the measured intensities corresponding to a fixed length of the streak are derived. A procedure for experimentally verifying the mathematical approach employed in these derivations is also presented. 相似文献