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城市建设理论研究—市政工程, 2022 论文对单掺粉煤灰自密实混凝土进行了坍落扩展度试验、T500试验、J环扩展度试验和GTM筛稳定性试验。结果表明：随着粉煤灰掺量增大，粉煤灰自密实混凝土坍落扩展度和J环扩展度呈先增后减的趋势，表明粉煤灰对自密实混凝土的流动性具有改善作用；粉煤灰掺量为20%时，粉煤灰自密实混凝土坍落扩展度和J环扩展度达到峰值587mm和571mm；T500随着粉煤灰掺量增大呈先减后增的趋势，表明粉煤灰的掺入可以提高自密实混凝土对多筋结构的适用性；SR结果表明粉煤灰的掺入可以改善自密实混凝土的抗离析性。
赵 建国
semanticscholar +1 more source
城市建设理论研究—建筑结构, 2022 论文针对煤矸石大量堆积占用土地、污染环境等问题，制备了水泥稳定煤矸石-碎石路面基层混合料，进行了击实试验、无侧限抗压强度试验和劈裂强度试验。试验结果表明：随着煤矸石替代率的增加，试件的最佳含水量增大，最大干密度降低，混合料的强度呈减小趋势，表明煤矸石的掺入对混合料的无侧限抗压强度和劈裂强度有不利影响。随着养生龄期的延长和水泥掺量的增大，混合料的强度呈增长趋势。7d龄期时，水泥掺量为5%，煤矸石替代率为50%时，混合料的无侧限抗压强度达到4.81MPa，满足中国二级及二级以下公路的技术要求。根据试验结果 ...
赵 建国
semanticscholar +1 more source
Current status and developing recommendations of tailings dam failure [PDF]
, 2018 This is the final version of the article. Available from Hindawi Publishing Corporation via the DOI in this record.Tailings dam failure accidents with limited emergency response time and huge potential threats, can often lead to heavy casualties and ...
Bu, L +4 more
core +1 more source
Experimental study on permeability evolution of slender coal pillar of entry driven along goaf [PDF]
, 2023 Under the condition of roadway driving along goaf, slender coal pillar is affected by multiple mining-induced disturbances, and the permeability of coal and rock mass affected by mining will change due to the development and compaction of mining ...
Bingjie HUO +5 more
core +1 more source
Gaoya dianqi, 2022 故障电流试验是晶闸管换流阀运行型式试验中重要的试验项目之一，国内外对故障电流施加方式的研究已较为深入，但对电流过零后如何立即施加恢复电压的试验方案则研究较少。通过研究国内外故障电流试验回路的发展现状，文中提出了一种采用工频电压发生器施加恢复电压的试验回路，介绍了其施加预期恢复电压的试验方法，计算确定了试验回路设备的参数，最后通过仿真验证了单波次和多波次故障电流试验中恢复电压施加方案的可行性。文中的研究成果已成功应用于某公司自主建设的晶闸管换流阀故障电流试验系统，并开展了晶闸管换流阀组件的故障电流试验 ...
王杰峰, 任军辉, 张树楠, 曹洋
doaj
Study on bearing deformation characteristics and lateral pressure distribution law of caved gangue in gob [PDF]
, 2023 Under the load of overlying strata, lateral pressure from the caved gangue in gob will be exerted on the support body of gob-side entry retaining or coal pillar.
Hailong WANG +3 more
core +1 more source
Gaoya dianqi, 2021 文中对进行过不同试验的550 kV GIS断路器用绝缘拉杆进行了孔隙性试验,研究不同试验结果对绝缘拉杆材料内部致密性的影响.根据试验研究结果,文中提出对每批产品应增加抽样试验项目—孔隙性试验,进一步排除不合格品,提高产品整体性能。
王昊 +6 more
doaj
The Experimental Study on Flow Boiling Heat Transfer of Working Fluid R245fa in Horizontal Tube [PDF]
, 2017 设计了管内沸腾换热系数及总传热系数测定试验台架,对R245fa工质在内径6 mm水平光管内的流动沸腾换热特性进行试验研究。测试质流密度为50 ~; 150 kg /(m~2·s),工质蒸发温度为50, 60和70℃。结果表明:; 随着工质含汽率的增加,R245fa的流动沸腾换热系数呈先增大后降低趋势。对于304不锈钢套管式换热器,烟气与R245fa工质进行换热的总传热系数; 约在40 ~ 65 W/(m~2·K) 。A bench - scale facility was designed for ...
刘美丽 +4 more
core +1 more source
Review and prospect of coal rock hydraulic fracturing physical experimental research [PDF]
, 2022 Physical simulation of hydraulic fracturing is an approximate representation of fracture evolution and its dynamic process, which represents an important direction of fracture evolution research.
Le LIU +8 more
core +1 more source
基于改进CNN-BiLSTM模型和地磁监测数据的多时间长度GIC预测
Kongjian kexue xuebao太阳风暴在电力系统网络中驱动产生的GIC会影响电力设备和系统的安全运行, 严重时还会引发大面积停电事件. 预测电网GIC水平能够为电力系统保护措施提供重要参考, 然而对这方面的研究仍显不足. 为了解决该问题, 将卷积神经网络(CNN)与双向长短时记忆(BiLSTM)以及注意力机制相结合, 利用空间天气的相关监测信息, 提出了大规模电网GIC多时间长度的预测方法.
蓝 东亮 +6 more
doaj +1 more source