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Theoretical analysis of a new segmented anchoring style in weakly cemented soft surrounding rock

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International Journal of Mining Science and Technology 2016年第3期26卷 401-407页

作者： zhao zenghui Wang Weiming Wang Lihua Shandong Provincial Key Laboratory of Civil Engineering Disaster Prevention and Mitigation Shandong University of Science & Technology State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science & Technology College of Mining and Safety Engineering Shandong University of Science & Technology College of Civil Engineering and Architecture Shandong University of Science & Technology

According to the tensile failure of rock bolt in weakly cemented soft rock, this paper presents a new segmented anchoring style in order to weaken the cumulative effect of anchoring force associated with the large deformation. Firstly, a segmented mechanical model was established in which free and anchoring section of rock bolt were respectively arranged in different deformation zones. Then, stress and displacement in elastic non-anchoring zone, elastic anchoring zone, elastic sticking zone, softening sticking zone and broken zone were derived respectively based on neural theory and tri-linear strain softening constitutive model of soft rock. Results show that the anchoring effect can be characterized by a supporting parameter b. With its increase, the peak value of tangential stress gradually moves to the roadway wall, and the radial stress significantly increases, which means the decrease of equivalent plastic zone and improvement of confining effect provided by anchorage body. When b increases to 0.72, the equivalent plastic zone disappears, and stresses tend to be the elastic solutions. In addition, the anchoring effect on the displacement of surrounding rock can be quantified by a normalization factor δ.

关键词： Weakly cemented soft rock Segmented anchorage Strain softening Analytical model

Shear behaviour of anchored jointed rock mass under different engineering conditions considering damage and joint surface morphology

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Underground Space 2023年第6期13卷 316-334页

作者： zenghui zhao Wei Sun Shaojie Chen Hao Liu College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Strata Intelligent Control and Green Mining Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China Department of Petroleum Engineering China University of Petroleum-BeijingBeijing 102249China

According to different geological conditions and engineering disturbance,three dimensional numerical models of anchored jointed rock mass with two kinds of boundary conditions of constant normal load(CNL)and constant normal stiffness(CNS)were constructed considering the ductility damage of rockbolt,the stiffness degradation of grouting layer and the joint surface *** effects of anchorage angle,joint surface morphology,and boundary conditions on the shear performance of anchorage system were analyzed,and the failure characteristics under different working conditions were ***,the analytical solution of shear strength of anchored system was *** show that the larger the anchorage angle is,the more serious the necking phenomenon of rockbolt will *** damage degree of the bonding layer and the horizontal displacement of the bedding rock mass decrease with the increase of the joint surface *** CNL condition is to instantaneously apply high normal stress,and the CNS condition is to gradually form a high normal stress environment through the superposition of increment on the basis of the initial value,which can resist greater transverse *** is equivalent to enhancing the ductility of the *** shear strength of the system increases with the increase of normal stress and normal *** the normal stiffness will underestimate the shear strength.

关键词： Anchored jointed rock mass Normal stress Normal stiffness Progressive damage

Displacement of surrounding rock in a deep circular hole considering double moduli and strength-stiffness degradation

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Applied Mathematics and Mechanics(English Edition) 2020年第12期41卷 1847-1860页

作者： zenghui zhao WeiSUN Shaojie CHEN Yuanhui FENG Weiming WANG College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Qingdao 266590Shandong ProvinceChina College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina

The problem of cavity stability widely exists in deep underground engineering and energy ***,the stress field of the surrounding rock under the uniform stress field is deduced based on a post-peak strength drop model considering the rock’s characteristics of constant modulus and double ***,the orthogonal non-associative flow rule is used to establish the displacement of the surrounding rock under constant modulus and double moduli,respectively,considering the stiffness degradation and dilatancy effects in the plastic region and assuming that the elastic strain in the plastic region satisfies the elastic constitutive ***,the evolution of the displacement in the surrounding rock is analyzed under the effects of the double modulus characteristics,the strength drop,the stiffness degradation,and the *** results show that the displacement solutions of the surrounding rock under constant modulus and double moduli have a unified *** coefficients of the expression are related to the stress field of the original rock,the elastic constant of the surrounding rock,the strength parameters,and the dilatancy *** strength drop,the stiffness degradation,and the dilatancy effects all have effects on the *** effects can be characterized by quantitative relationships.

关键词： deep rock double moduli strength-stiffness degradation circular hole displacement solution

Quantitative analysis of parameters’influence on the stability of coal roadway clamped by upper and lower soft rock with extra thickness

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International Journal of Modeling, Simulation, and Scientific Computing 2014年第2期5卷 25-39页

作者： zenghui zhao Weiming Wang Jixing Yan College of Civil Engineering of Shandong University of Science and Technology Qingdao Shandong 266590P.R.China

In this paper,a physical model of coal roadway which is clamped by upper and lower softrock with extra thickness was built according to the characteristics of soft rock strata in china's western mining ***,a series of orthogonal numerical experiments were carried out by selecting the strength and stiffness parameters of soft rock and coal seam as well as the in situ stress of soft rock strata as experimental factors and roadway displacements(convergence displacements of sides,displacement of roof to floor)as experimental *** constructing the F statistics with different inspection levels,evaluation method for influence of the experimental factors on stability indexes were ***,influence degrees of specified parameters on the stability of roadway were divided into five classes as follows:highly significant influence,significant influence,relatively significant influence,little significant influence,and no influence respectively which realize the quantitative analysis of the influence degrees of experimental *** finite element calculation results showed that main failure mode of coal roadway that usually showed as tension failure of coal seam in roof and deformation factors of coal seam had the most remarkable effect on roadway *** conclusions provide theoretical basis for further analysis of the mechanism of"roof burst"in roadway maintenance.

关键词： Upper and lower soft rock with extra thickness coal roadway orthogonal experiment stability influence degree quantitative analysis

计及光伏波动性的主动配电网双层有功无功协调优化

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电力系统及其自动化学报 2024年第5期36卷 19-26页

作者：卢锦玲赵增辉胡兴华张学哲王恩泽华北电力大学电气与电子工程学院保定071000

针对含有高比例分布式电源的配电网在源荷不确定性和协调多种无功补偿设备等方面存在的问题,提出一种主动配电网双层有功无功协调优化策略。该策略首先针对离散型出力的有载调压变压器和电容器组,以网损和电压偏差为目标,建立上层优化模... 详细信息

针对含有高比例分布式电源的配电网在源荷不确定性和协调多种无功补偿设备等方面存在的问题,提出一种主动配电网双层有功无功协调优化策略。该策略首先针对离散型出力的有载调压变压器和电容器组,以网损和电压偏差为目标,建立上层优化模型;其次,下层优化模型通过储能出力平抑光伏的有功波动,同时通过调整静止无功补偿装置、光伏逆变器弥补光伏并网点的无功缺额,以配电网的有功波动和光伏并网点的电压偏差为目标,并采用改进的多目标粒子群优化算法求解该模型;最后,通过IEEE 33节点算例验证所提策略的有效性。该优化策略不仅提高了有功与无功的协调性,且实时性强,不依赖精准的设备控制,使配电网的经济性和可靠性得到提升。

关键词：主动配电网协调优化有功波动光伏并网点多目标粒子群优化算法

基于负荷预测和无迹粒子滤波的配电网动态状态估计

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电力系统及其自动化学报 2024年第4期36卷 133-140,158页

作者：卢锦玲胡兴华张学哲王恩泽赵增辉华北电力大学电气与电子工程学院保定071003

随着汽车充电成为新型重要负荷,为确保此时配电网运行与控制安全,对其进行实时准确的态势感知,提出一种基于卷积神经网络和门控循环单元的短期负荷预测与无迹粒子滤波算法自适应混合的配电网动态状态估计方法。结合使用卷积神经网络和... 详细信息

随着汽车充电成为新型重要负荷,为确保此时配电网运行与控制安全,对其进行实时准确的态势感知,提出一种基于卷积神经网络和门控循环单元的短期负荷预测与无迹粒子滤波算法自适应混合的配电网动态状态估计方法。结合使用卷积神经网络和门控循环单元进行短期负荷预测,将预测得到的有功与无功功率进行潮流计算,再与无迹粒子滤波量测估计值自适应加权得到电压幅值和相角状态估计结果。以IEEE33节点配电网为例,验证了所提状态估计方法的准确性与面对不良数据时的鲁棒性。

关键词：配电网电动汽车负荷预测无迹粒子滤波动态状态估计

基于主成分分析法的全国道路交通安全水平分析

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安全 2024年第1期45卷 26-30页

作者：赵增辉黄丽华荆海涛李伟杰首都经济贸易大学管理工程学院北京100070 中铁十一局集团有限公司湖北武汉430061

为清晰、直观地分析全国各地区的道路交通安全水平,采用主成分分析法,以万车死亡率、万车受伤率、万车事故损失(万元)、万车事故率为指标,分析2013—2022年全国道路交通安全水平的变化。结果表明:2013—2022年,全国道路交通安全水平呈... 详细信息

为清晰、直观地分析全国各地区的道路交通安全水平,采用主成分分析法,以万车死亡率、万车受伤率、万车事故损失(万元)、万车事故率为指标,分析2013—2022年全国道路交通安全水平的变化。结果表明:2013—2022年,全国道路交通安全水平呈现逐步上升的趋势;2015和2020年,上海是道路交通安全水平均保持第一的城市,重庆是道路交通安全水平进步最大的城市。结合这2座城市交通安全治理经验提出扩建和改造路网、建设和优化公共交通、提高道路通行效率、完善法规建设、加强执法力度、加强对驾驶员和行人的教育和管理等提高道路交通安全水平的对策措施。

关键词：道路交通安全评价主成分分析交通安全

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聚合物微细纤维的成型及其抗菌功能改性进展

上海纺织科技 2024年第9期52卷 1-6,24页

作者：赵增辉李志俞森龙周家良胡泽旭相恒学朱美芳中国石油天然气股份有限公司大庆化工研究中心黑龙江大庆163714 东华大学纤维材料改性国家重点实验室材料科学与工程学院上海201620

聚合物微细纤维具有比表面积大、孔隙率高的特点,在防护服、口罩等医卫防护领域具有广泛应用。然而,沾染致病菌、病毒后,微细纤维也可成为传播微生物的媒介,导致“二次感染”。介绍了纤维的静电纺、闪蒸纺等成型进展,分析了不同方法制... 详细信息

聚合物微细纤维具有比表面积大、孔隙率高的特点,在防护服、口罩等医卫防护领域具有广泛应用。然而,沾染致病菌、病毒后,微细纤维也可成为传播微生物的媒介,导致“二次感染”。介绍了纤维的静电纺、闪蒸纺等成型进展,分析了不同方法制备纤维的结构特征;其次,从纤维负载天然、有机、无机和金属基抗菌材料3个方面,分析了抗菌材料赋予纤维的抗菌特性及其机制;最后,对聚合物微细纤维的发展趋势进行了展望。

关键词：聚合物微细纤维抗菌功能主动防护医卫纺织材料

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聚丙烯催化剂聚合性能的研究

合成树脂及塑料 2011年第1期28卷 33-35,39页

作者：赵增辉中国石油天然气股份有限公司石油化工研究院大庆化工研究中心黑龙江大庆163714

采用磷酸酯类作内给电子体,MgCl_2作载体合成球形聚丙烯催化剂,以三乙基铝为助催化剂,甲基环已基二甲氧基硅烷为外给电子体,研究液相本体法聚合条件对催化剂性能的影响,并对聚合物进行了分析。结果表明:该催化体系最佳聚合条件为搅拌转... 详细信息

采用磷酸酯类作内给电子体,MgCl_2作载体合成球形聚丙烯催化剂,以三乙基铝为助催化剂,甲基环已基二甲氧基硅烷为外给电子体,研究液相本体法聚合条件对催化剂性能的影响,并对聚合物进行了分析。结果表明:该催化体系最佳聚合条件为搅拌转速150 r/min,反应温度75℃,n(A1)/n(Ti)为600,n(Si)/n(Ti)为30。在此条件下,催化体系为长效型,催化剂活性高、氢调敏感性好,聚合物等规指数高、细粉少。

关键词：聚丙烯齐格勒-纳塔催化剂磷酸酯给电子体聚合