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建筑电气 2024年第3期43卷 14-19,4页

作者：曹立强中国建筑东北设计研究院有限公司沈阳市110006

论述自动切断电源作间接接触保护的校验的必要性,对超高层建筑的典型配电回路进行单相接地短路电流计算及断路器灵敏度校验,通过对提升灵敏度措施的比较分析,提供几点超高层建筑断路器和电缆选择的建议。

关键词：超高层建筑 TN系统配电回路接地故障电流自动切断电源间接接触保护断路器灵敏度校验

可再分散乳胶粉对钢结构界面砂浆的性能影响和机理分析

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硅酸盐通报 2024年第6期43卷 1999-2004页

作者：王小燕叶武平曹力强中国建筑科学研究院有限公司北京100013 建筑安全与环境国家重点实验室北京101100

可再分散乳胶粉是钢结构界面砂浆制备的关键材料。本文研究了可再分散乳胶粉的掺量对界面砂浆28 d抗压强度、抗折强度、拉伸黏结强度的影响,同时结合扫描电镜、X射线衍射等微观分析手段对可再分散乳胶粉提升界面砂浆的黏结性机理进行了... 详细信息

可再分散乳胶粉是钢结构界面砂浆制备的关键材料。本文研究了可再分散乳胶粉的掺量对界面砂浆28 d抗压强度、抗折强度、拉伸黏结强度的影响,同时结合扫描电镜、X射线衍射等微观分析手段对可再分散乳胶粉提升界面砂浆的黏结性机理进行了分析。结果表明:在钢结构界面砂浆的制备中,可再分散乳胶粉的适宜掺量为15%(质量分数);在适宜掺量下,界面砂浆的拉伸黏结强度达到1.12 MPa,压折比为2.3,乳胶粉的加入能有效改善砂浆柔韧性;乳胶粉的加入改变了砂浆的孔结构,孔隙率变大;界面过渡区的水化产物主要是聚合膜包裹水化产物C-S-H凝胶和Ca(OH)_(2)。

关键词：可再分散乳胶粉钢结构界面砂浆力学性能韧性孔结构微观分析

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基于健康指数的电力变压器绝缘状态评估方法研究

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高压电器 2024年第5期60卷 124-129页

作者：江涛杨传凯王荆黄国强曹利强师一卿国网陕西省电力公司西安710049 国网陕西省电力公司电力科学研究院西安710049

为科学合理地评估在运电力变压器的健康水平,根据变压器关键特征信息,建立了由本体数据、在运数据、修正系数构成的三级评估模型。引入健康指数理论,分析了反应变压器绝缘状态的不同关键特征信息的权重,提出了变压器三级评估模型健康水... 详细信息

为科学合理地评估在运电力变压器的健康水平,根据变压器关键特征信息,建立了由本体数据、在运数据、修正系数构成的三级评估模型。引入健康指数理论,分析了反应变压器绝缘状态的不同关键特征信息的权重,提出了变压器三级评估模型健康水平的计算方法,并在此基础上得出变压器剩余寿命计算公式。最后结合一个实际案例,证明了该方法能科学、准确地评估电网在运电力变压器的绝缘状态,为工程技术人员评估变压器绝缘状态和剩余寿命提供参考。

关键词：电力变压器绝缘状态评估健康指数寿命预测

Analytical study on pretensioned bolt-cable combined support of large cross-section tunnel

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Science China(Technological Sciences) 2020年第9期63卷 1808-1823页

作者： LUO JiWei ZHANG DingLi FANG Qian LI Ao SUN ZhenYu cao liqiang Key Laboratory for Urban Underground Engineering of the Ministry of Education Beijing Jiaotong UniversityBeijing 100044China

To study the mechanical responses of large cross-section tunnel reinforced by pretensioned rock bolts and anchor cables, an analytical model is proposed. Considering the interaction between rock mass and bolt-cable support, the strain softening characteristic of rock mass, the elastic-plastic characteristic of bolt-cable support, and the delay effect of installation are considered in the model. To solve the different mechanical cases of tunneling reinforced by bolt-cable support, an analytical approach has been put forward to get the solutions of stress and displacement associated with tunneling. The proposed analytical model is verified by numerical simulation. Moreover, parametric analysis is performed to study the effects of pretension force,cross-section area, length, and supporting density of bolt-cable support on tunnel reinforcement, which can provide references for determining these parameters in tunnel design. Based on the analytical model, a new Ground Response Curve(GRC)considering the reinforcement of bolt-cable support is obtained, which shows the pretension forces and the timely installation are important in bolt-cable support. In addition, the proposed model is applied to the analysis of the Great Wall Station Tunnel, a high-speed railway tunnel with a super large cross-section, which shows that the analytical model of bolt-cable support was a useful tool for preliminary design of large cross-section tunnel.

关键词： bolt-cable combined support analytical model pretension force large cross-section tunnel reinforcement

Analytical modeling of complex contact behavior between rock mass and lining structure

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第3期14卷 813-824页

作者： Dingli Zhang Tong Xu Huangcheng Fang Qian Fang liqiang cao Ming Wen Key Laboratory for Urban Underground Engineering of the Ministry of Education Beijing Jiaotong UniversityBeijing100044China College of Civil and Transportation Engineering Shenzhen UniversityShenzhen518060China China Academy of Transportation Sciences Beijing100029China

Based on the nondestructive test data of operating railway tunnels in China, this paper summarizes the basic characteristics of the complex contact behavior between the rock mass and lining structure. The contact modes are classified into dense contact, local non-contact, and loose contact. Subsequently, the corresponding mechanical model for each contact mode is developed according to its mechanical characteristics using the complex variable method. In the proposed mechanical model, a special algorithm is introduced to detect whether the local non-contact zone is re-contacted. Besides, a novel conformal mapping method is also proposed to accurately calculate the mechanical response of the concrete lining. Finally, the accuracy of the proposed method is verified by comparing it with the finite element method(FEM). Several parameter investigations are conducted to analyze the effects of different contact modes on the rock-lining interaction. The results show that:(i) the height of the local noncontact area does not have a significant effect on the contact stress distribution if no re-contact occurs;(ii) backfill grouting can reduce the local stress concentration caused by poor contact modes;and(iii) reducing the friction coefficient of the interface can lead to a more uniform distribution of internal forces in the concrete lining.

关键词： Loose contact Local non-contact Tunnel lining Complex variable method Analytical mechanical model

Analytical solutions for the restraint effect of isolation piles against tunneling-induced vertical ground displacements

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第10期15卷 2582-2596页

作者： liqiang cao Xiangsheng Chen Xing-Tao Lin Dong Su Huangcheng Fang Dechun Lu Institute of Geotechnical and Underground Engineering Beijing University of TechnologyBeijing100124China Underground Polis Academy Shenzhen UniversityShenzhen518060China College of Civil and Transportation Engineering Shenzhen UniversityShenzhen518060China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

This paper presents a simplified elastic continuum method for calculating the restraint effect of isolation piles on tunneling-induced vertical ground displacement,which can consider not only the relative sliding of the pile‒soil interface but also the pile rowesoil *** proposed method is verified by comparisons with existing theoretical methods,including the boundary element method and the elastic foundation *** results reveal the restraining mechanism of the isolation piles on vertical ground displacements due to tunneling,*** positive and negative restraint effects exerted by the isolation piles jointly drive the ground vertical displacement along the depth direction from the original tunneling-induced nonlinear variation situation to a relatively uniform *** results also indicate that the stiffness of the pile‒soil interface,including the pile shaft‒surrounding soil interface and pile tip-supporting soil interface,describes the strength of the pile‒soil *** pile rows can confine the vertical ground displacement caused by the tunnel excavation to the inner side of the isolation piles and effectively prevent the vertical ground displacement from expanding further toward the outer side of the isolation piles.

关键词： Restraining mechanism Restraint effect Isolation piles Ground displacement Tunneling

维普期刊数据库评论

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外墙外保温技术性能评价指标体系探索

北方建筑 2024年第3期9卷 109-114页

作者：申和庆叶武平曹力强牛翠兵中国建筑科学研究院有限公司北京100013 建研建材有限公司北京100013

随着外墙外保温系统技术的不断发展和完善,对其性能综合评价也提出了更高的要求。针对现有综合性能评价指标体系相对片面的问题,通过文献调研、专家咨询、经验总结和实地调研,归纳总结出了外墙外保温系统的综合性能评价指标体系,并基于... 详细信息

随着外墙外保温系统技术的不断发展和完善,对其性能综合评价也提出了更高的要求。针对现有综合性能评价指标体系相对片面的问题,通过文献调研、专家咨询、经验总结和实地调研,归纳总结出了外墙外保温系统的综合性能评价指标体系,并基于层次分析法建立了综合评价方法,从而得到较为系统的外墙外保温综合性能评价结果,为具体外墙外保温技术的适宜性和优越性评价提供了依据和参考。

关键词：外保温性能评价指标体系安全性

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重晶砂掺量对抹灰隔声砂浆性能的影响研究

混凝土与水泥制品 2024年第8期 71-74页

作者：申和庆曹力强叶武平王小燕梁瑞华中国建筑科学研究院有限公司北京100013 建研建材有限公司北京100013

采用重晶砂等体积替代机制砂(0、20%、40%、60%、80%和100%),研究了重晶砂掺量对抹灰隔声砂浆干表观密度、分层度、抗压强度、抗折强度、拉伸黏结强度、空气声隔声量的影响。结果表明:采用重晶砂替代机制砂可有效提高砂浆的干表观密度,... 详细信息

采用重晶砂等体积替代机制砂(0、20%、40%、60%、80%和100%),研究了重晶砂掺量对抹灰隔声砂浆干表观密度、分层度、抗压强度、抗折强度、拉伸黏结强度、空气声隔声量的影响。结果表明:采用重晶砂替代机制砂可有效提高砂浆的干表观密度,最大可达3040 kg/m^(3);随着重晶砂掺量的增加,分层度先增加后降低,抗折强度、抗压强度和拉伸黏结强度均逐渐降低;掺入重晶砂可提高轻质隔墙的空气声隔声量,当掺量为100%时,隔声效果最好,较空白组砂浆的空气声隔声量提高了3 dB,较裸墙提高了7 dB。

关键词：隔声砂浆重晶砂隔声量抗压强度

Preparation and Photostriction Properties of BiFeO_(3)-BaTiO_(3)Ceramics

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1079-1086页

作者： ZHENG Zewei ZHANG liqiang CHEN Chen cao Minghe YI Zhiguo LIU Hanxing School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China School of Microelectronics Shanghai UniversityShanghai 200444China International School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

Under illumination by 405,520 and 655 nm monochromatic visible light(light intensity of 30 kW/m^(2)),large photostriction(ΔL/L)of 0.19%,0.13%and 0.26%for 67BiFeO_(3)-33BaTiO_(3)(67BF-33BT)lead-free ferroelectric ceramics are obtained,*** studying the ferroelectric and photoelectric properties in conjunction with in situ Raman spectroscopy,it is found that the photostrictive effect of 67BF-33BT is not caused by the electrical strain induced by abnormal photovoltaic voltage,but related to the optical induced oxygen octahedral *** 67BF-33BT lead-free ferroelectric material with excellent photostrictive response in the visible light region is expected to play an important role in the field of optical drive electromechanical devices.

关键词： ferroelectric ceramics photostrictive effect visible light response

A novel dual-lens-coupling system for DFB laser based on hybrid integration

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Optoelectronics Letters 2021年第7期17卷 395-399页

作者： WEI Juan SUN Yu XUE Haiyun HE Huimin SUN Siwei LIU Fengman cao liqiang System Packaging and Integration Research Center Institute of Microelectronics of Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100059China National Center for Advanced Packaging Wuxi 214028China

A dual-lens-integrated distributed feedback(DFB) laser based on hybrid integration for single-mode transmitter optical subassembly(TOSAs) is discussed in this paper. The alignment and fixing of the lenses are simple to manipulate and highly accurate, making it possible to achieve high-efficient optical coupling to single-mode fiber(SMF) without additional high-precision tools and fixing equipment. The capability for a low coupling loss of less than 3 d B between the laser and fiber was demonstrated. The fabricated TOSA module has clear opening eyes with minor time jitters at a bit rate of 25 Gbit/s. This hybrid integration is a low fabrication cost, compact, and low insertion loss method to manufacture TOSA for a 200 or 400 Gb E optical transceiver in a high-speed optical network.

关键词： laser fiber coupling