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Analysis of the Behavior of a Square Plate in Free Vibration by FEM in Ansys 认领
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作者 Pascal Kuate Nkounhawa Dieunedort Ndapeu +1 位作者 Bienvenu Kenmeugne Tibi Beda 《力学国际期刊(英文)》 2020年第2期11-25,共15页
In the realization of mechanical structures, achieving stability and balance is a problem commonly encountered by engineers in the field of civil engineering, mechanics, aeronautics, biomechanics and many others. The ... In the realization of mechanical structures, achieving stability and balance is a problem commonly encountered by engineers in the field of civil engineering, mechanics, aeronautics, biomechanics and many others. The study of plate behavior is a very sensitive subject because it is part of the structural elements. The study of the dynamic behavior of free vibration structures is done by modal analysis in order to calculate natural frequencies and modal deformations. In this paper, we present the modal analysis of a thin rectangular plate simply supported. The analytical solution of the differential equation is obtained by applying the method of separating the variables. We are talking about the exact solution of the problem to the limit values. However, numerical methods such as the finite element method allow us to approximate these functions with greater accuracy. It is one of the most powerful computational methods for predicting dynamic response in a complex structure subject to arbitrary boundary conditions. The results obtained by MEF through Ansys 15.0 are then compared with those obtained by the analytical method. 展开更多
关键词 Free VIBRATION VIBRATION Modes MODAL ANALYSIS Natural Frequencies MODAL Deformations Thin Rectangular PLATE Finite Element Method (FEM)
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船用空调器振动及隔振措施分析 认领
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作者 莫立新 陈攀 周健 《舰船科学技术》 北大核心 2020年第6期71-74,共4页
空调器是船舶上广泛使用的辅机设备之一,其振动状态不仅影响周围居住舱室的居住环境,也影响全船的振动状态。本文开展了实船安装状态下某型空调器的振动测试及分析工作,并依据实际运行状态,分析空调器风机隔振、空调器整体单层隔振及空... 空调器是船舶上广泛使用的辅机设备之一,其振动状态不仅影响周围居住舱室的居住环境,也影响全船的振动状态。本文开展了实船安装状态下某型空调器的振动测试及分析工作,并依据实际运行状态,分析空调器风机隔振、空调器整体单层隔振及空调器双层隔振3种不同隔振措施对空调器振动传递的影响。经过对比分析,以上方式均可有效降低空调器振动传递至安装基础,其中空调器双层隔振方案的效果最佳,且可有效降低低频振动的传递。 展开更多
关键词 空调器 振动 单层隔振 双层隔振
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直升机主减液弹隔振技术的发展现状及趋势 认领
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作者 代志雄 钱峰 冯志壮 《航空科学技术》 2020年第6期19-26,共8页
直升机振动的主要来源是桨叶旋转过程中产生的桨毂激振力,这种激振力通过主减装置传递到机身,造成机身的剧烈振动,因此,降低旋翼以及机体的振动水平成为直升机动力学设计中的首要问题。液弹隔振器作为一种高效隔振、结构紧凑的隔振装置... 直升机振动的主要来源是桨叶旋转过程中产生的桨毂激振力,这种激振力通过主减装置传递到机身,造成机身的剧烈振动,因此,降低旋翼以及机体的振动水平成为直升机动力学设计中的首要问题。液弹隔振器作为一种高效隔振、结构紧凑的隔振装置,能够显著地降低桨叶旋转中产生的激振力的传递,从而降低飞机的振动水平,提高飞行质量。本文对被动及主动式液弹隔振技术国内外发展的现状进行了阐述,并对液弹隔振技术的工程应用的发展趋势进行了分析和展望。 展开更多
关键词 直升机 振动 液弹隔振 发展趋势
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1500℃极端高温环境下高超声速飞行器轻质隔热材料热/振联合试验 认领
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作者 吴大方 林鹭劲 +1 位作者 吴文军 孙陈诚 《航空学报》 EI CAS CSCD 北大核心 2020年第7期210-219,共10页
远程高超声速飞行器处于极为恶劣的气动加热与振动耦合环境中,长时间的高温与振动载荷相互叠加会导致飞行器热防护材料出现裂纹、错位、剥离或脱落,甚至会引发致命的安全事故。因此热防护材料在极端高温环境下的地面热/振联合试验测试,... 远程高超声速飞行器处于极为恶劣的气动加热与振动耦合环境中,长时间的高温与振动载荷相互叠加会导致飞行器热防护材料出现裂纹、错位、剥离或脱落,甚至会引发致命的安全事故。因此热防护材料在极端高温环境下的地面热/振联合试验测试,对于高超声速飞行器的安全可靠性设计极为重要。建立高温与振动复合试验环境,设法解决轻质多孔隔热材料在强振动下,表面温度难于准确测量与控制的难题,制作水冷式隔热装置保护价格昂贵的振动激励设备等,实现了1 500℃高温环境下高超声速飞行器轻质隔热材料的热/振联合试验。得到非金属隔热材料陶瓷纤维板内部的断裂形貌及裂纹断面特征。根据试验前、后材料的表观及微观变化以及内部结合剂的变化等试验结果,对材料进行改进。经过试验测试后,达到了使用要求。本文建立的1 500℃极端高温环境下的热/振联合试验系统及试验结果为远程高超声速飞行器热防护材料的抗振动能力评估、隔热效果确定以及材料性能的改进提供了重要支撑。 展开更多
关键词 高超声速飞行器 高温 振动 隔热材料 热/振联合试验
Vibration-Based Analysis for Detecting Turbocharger Blade Defect on High-Power Diesel Generator 认领
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作者 Metaga Jeremi Sogoba Badié Diourté Moussa Magara Traoré 《力学国际期刊(英文)》 2020年第1期1-10,共10页
This study is concerned with 12-MW capacity turbochargers on diesel power generators. These are generators equipped with 18 cylinders. Our previous studies [1] showed that the processing of vibration signature collect... This study is concerned with 12-MW capacity turbochargers on diesel power generators. These are generators equipped with 18 cylinders. Our previous studies [1] showed that the processing of vibration signature collected from a power generator is very complex, insomuch the dominant vibration remains the one originating from explosion frequency in the diesel generator cylinders, with a fairly high number of cylinders. This vibration drowns out all other possible vibrations, which can expose defects. The study at hand is focused on turbochargers with 20,940 rpm, while the rotation speed in the diesel engine is 600 rpm only. With the turbocharger rotating at very high speed, it results in severe mechanical constraints on the rotor shaft in the turbocharger and its related organs (turbine blades). The wear of turbine blades can result in breakdowns in the turbocharger. This article is an attempt to early detect defaults in turbine blades based on vibration signature that can be experimentally determined. We noted in our investigations that a diesel engine and its turbochargers do not bear the same mechanic loads. While the diesel engine is the seat of violent shocks brought about by explosions in cylinders, the turbochargers are driven by the action of exhaust gas from explosions, without being affected by explosion shocks. The study found that explosion frequency in the diesel engine cylinders, which disrupted the vibration signals in the diesel engine and alternator, did not impact on the vibration signals in the turbocharger. We experimentally determined, following several campaigns of measurements, a vibration signature on the turbochargers under study, which corresponds to a defect in turbine blades. 展开更多
关键词 VIBRATION Signature Fast Fourier Transform Method (FFT) TURBOCHARGER Tur-bine BLADES
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Simple and fast prediction of train-induced track forces,ground and building vibrations 认领
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作者 Lutz Auersch 《铁道工程科学:英文版》 2020年第3期232-250,共19页
A simple and fast prediction scheme is presented for train-induced ground and building vibrations.Simple models such as(one-dimensional)transfer matrices are used for the vehicle–track–soil interaction and for the b... A simple and fast prediction scheme is presented for train-induced ground and building vibrations.Simple models such as(one-dimensional)transfer matrices are used for the vehicle–track–soil interaction and for the building–soil interaction.The wave propagation through layered soils is approximated by a frequency-dependent homogeneous half-space.The prediction is divided into the parts“emission”(excitation by railway traffic),“transmission”(wave propagation through the soil)and“immission”(transfer into a building).The link between the modules is made by the excitation force between emission and transmission,and by the free-field vibration between transmission and immission.All formula for the simple vehicle–track,soil and building models are given in this article.The behaviour of the models is demonstrated by typical examples,including the mitigation of train vibrations by elastic track elements,the low-and high-frequency cut-offs characteristic for layered soils,and the interacting soil,wall and floor resonances of multi-storey buildings.It is shown that the results of the simple prediction models can well represent the behaviour of the more time-consuming detailed models,the finite-element boundary-element models of the track,the wavenumber integrals for the soil and the three-dimensional finite-element models of the building.In addition,measurement examples are given for each part of the prediction,confirming that the methods provide reasonable results.As the prediction models are fast in calculation,many predictions can be done,for example to assess the environmental effect along a new railway line.The simple models have the additional advantage that the user needs to know only a minimum of parameters.So,the prediction is fast and user-friendly,but also theoretically and experimentally well-founded. 展开更多
关键词 Railway-induced vibration Ground vibration Layered soil Building response Excitation forces Track and vehicle irregularities
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基于制振合金的机枪遥控武器站减振技术研究 认领
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作者 朱锐 毛保全 +1 位作者 辛学敏 杨雨迎 《计算机仿真》 北大核心 2020年第9期25-30,共6页
机枪遥控武器站高低向半齿轮结构的振动问题是影响武器站射击密集度提高的关键。在大口径机枪射击过程中,高低向半齿轮的振动呈现低频小位移的特点。半齿轮结构要求保持一定的刚度来耗散吸收摇架相对运动带来的多余能量,确保射向不发生... 机枪遥控武器站高低向半齿轮结构的振动问题是影响武器站射击密集度提高的关键。在大口径机枪射击过程中,高低向半齿轮的振动呈现低频小位移的特点。半齿轮结构要求保持一定的刚度来耗散吸收摇架相对运动带来的多余能量,确保射向不发生偏移。采用制振合金(Mn-20Cu-5Ni-2Fe)减振技术可以在不减少结构刚度的前提下,增加系统阻尼,达到减振目的。对采用制振合金优化后的半齿轮结构进行振动分析和阻尼特性试验,结果显示制振合金减振技术可以使振动加速度幅值降低35.28%,具有良好应用前景。 展开更多
关键词 振动 制振合金 减振技术 半齿轮结构
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某人行桥舒适性与减振措施分析 认领
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作者 潘晓东 《江苏建筑》 2020年第3期58-60,92,共4页
文章以某大跨度人行桥为背景,通过理论分析和有限元模拟,对桥梁在行人激励下的动力响应及行人舒适性进行评价,依据评价结果提出减振方案。
关键词 人行桥 振动 减振 TMD
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连铸机振动参数优化实践研究 认领
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作者 雷晶 吴国臣 《世界有色金属》 2020年第6期57-58,61,共3页
本文针对本厂连铸机改造前后不同振动形式的优缺点进行对比分析,通过合理的振动参数设定和配套保护渣性能指标优化,从现场实践生产跟踪固化进行了一系列分析总结,保障了连铸的生产效率提高和事故率降低,同时得到了较好的铸坯表面质量。
关键词 振动 非正弦振动 保护渣 表面质量
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多级立式泵动力吸振器设计与分析 认领
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作者 陈玉球 《机械工程师》 2020年第1期129-130,134共3页
以某多级立式水泵为研究对象,在ANSYS Workbench中完成了泵组的模态分析,并按照最优阻尼原则计算出动力吸振器的参数,对含有吸振器的泵组进行谐响应分析,结果表明动力吸振器有效地抑制了振动。
关键词 振动 动力吸振器 模态分析
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燃气轮机转子裂纹故障分析与诊断 认领
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作者 赵卫正 童小忠 +1 位作者 谢尉扬 张卫 《燃气轮机技术》 2020年第1期54-58,共5页
振动监测和诊断是及时诊断旋转机械故障的手段之一,其中的频谱分析能有效地诊断出转子裂纹。介绍了某燃气轮机转子裂纹的振动现象、处理过程以及故障诊断。转子裂纹的振动有以下特征:裂纹转子具有刚度不对称的特点,运行中存在二倍频振动... 振动监测和诊断是及时诊断旋转机械故障的手段之一,其中的频谱分析能有效地诊断出转子裂纹。介绍了某燃气轮机转子裂纹的振动现象、处理过程以及故障诊断。转子裂纹的振动有以下特征:裂纹转子具有刚度不对称的特点,运行中存在二倍频振动,在启停机经过转子临界转速一半时存在二倍频共振峰;随着裂纹的发展,二倍频共振峰值有增大趋势;联轴器瓢偏以及低速盘车时转子晃度也会增大。根据转子的振动特征判断该转子存在裂纹且仍在发展,检查结果验证了故障诊断的正确性,为转子裂纹的故障分析与诊断提供参考。 展开更多
关键词 转子 裂纹 振动 二倍频 故障诊断
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The Effects of Freight Vibrations on Slope Stability along the SH35, Bay of Plenty East, New Zealand 认领
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作者 Angelo Indelicato 《地球科学和环境保护期刊(英文)》 2020年第5期335-345,共11页
State Highway 35 (SH35) connects Opotiki to Gisborne along the Raukumara Peninsula in the North Island, New Zealand. This corridor passes through an area which is prone to landslides, especially during the wet season.... State Highway 35 (SH35) connects Opotiki to Gisborne along the Raukumara Peninsula in the North Island, New Zealand. This corridor passes through an area which is prone to landslides, especially during the wet season. This, in turn, influences the traffic and has detrimental effects to the local economy, as it is dependent mainly on tourism and commercial transportation by road. This paper will focus on the landslides which occurred between June and September 2018, within the Bay of Plenty East on the north side of the Raukumara Peninsula. The paper will analyze both the nature and triggering mechanisms behind these landslides. As the landslides occur in the wet season, rainfall has been commonly considered the main trigger. However, the paper will argue that vehicle vibrations have been contributing to the instability of the slopes within the Bay of Plenty East. This paper will be instrumental in developing future transportation strategies in this part of the North Island. 展开更多
关键词 Landslide TRIGGER Mechanisms FREIGHT Vibration BAY of Plenty EAST Raukumara PENINSULA New Zealand
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轨道交通与路面交通振动对实验室环境的影响测试 认领
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作者 刘辉 《中国市政工程》 2020年第3期82-85,133,134,共6页
当前城市快速发展,城市轨道交通建设越来越多,由此引起的环境振动问题也备受关注,尤其对有精密仪器的办公厂房或实验室。以上海市浦东新区计量质量检测所(惠南分部)为背景,在实验室内布置振动传感器,通过测试工作日轨道交通运行、道路... 当前城市快速发展,城市轨道交通建设越来越多,由此引起的环境振动问题也备受关注,尤其对有精密仪器的办公厂房或实验室。以上海市浦东新区计量质量检测所(惠南分部)为背景,在实验室内布置振动传感器,通过测试工作日轨道交通运行、道路车辆运行和轨道交通停运时不同情况下的振动响应,分析和评估不同交通工况下的环境振动对实验室内精密仪器正常工作的影响,以便采取必要的减震措施确保精密仪器能正常工作。 展开更多
关键词 振动 精密仪器 测试 轨道交通 道路车辆 振动响应
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A two degree of freedom stable quasi-zero stiffness prototype and its applications in aseismic engineering 认领
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作者 ZHU GuangNan LIU JiYe +3 位作者 CAO QingJie CHENG YongFeng LU ZhiCheng ZHU ZhuBing 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2020年第3期496-505,共10页
In this paper, an archetypal aseismic system is proposed with 2-degree of freedom based on a smooth and discontinuous(SD)oscillator to avoid the failure of electric power system under the complex excitation of seismic... In this paper, an archetypal aseismic system is proposed with 2-degree of freedom based on a smooth and discontinuous(SD)oscillator to avoid the failure of electric power system under the complex excitation of seismic waves. This model comprises two vibration isolation units for the orthogonal horizontal directions, and each of them admits the stable quasi-zero stiffness(SQZS)with a pair of inclined linear elastic springs. The equation of motion is formulated by using Lagrange equation, and the SQZS condition is obtained by optimizing the parameters of the system. The analysis shows that the system behaves a remarkable vibration isolation performance with low resonant frequency and a large stroke of SQZS interval. The experimental investigations are carried out to show a high sonsistency with the theoretical results, which demonstrates the improvement of aseismic behavior of the proposed model under the seismic wave. 展开更多
关键词 SD oscillator two-DOF VIBRATION ISOLATION STABLE quasi-zero STIFFNESS low-frequency VIBRATION ISOLATION aseismic experiment
Influence of mill modulus control gain on vibration in hot rolling mills 认领
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作者 Jie-bin Qi Xin-xin Wang Xiao-qiang Yan 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2020年第5期528-536,共9页
The rolling mill vibration is characterized by the coupling effects among mechanical,electrical,hydraulic and interfacial subsystems.The influence of the mill modulus control gain in automatic gauge control on the vib... The rolling mill vibration is characterized by the coupling effects among mechanical,electrical,hydraulic and interfacial subsystems.The influence of the mill modulus control gain in automatic gauge control on the vibration in hot rolling mills was investigated.Firstly,an experiment related to the mill modulus control gain was carried out in the hot rolling mill process,and it was found that the rolling mill vibration increases with the mill modulus control gain.Then,based on the Sims rolling force method,the coupling dynamic model was established to explain this phenomenon.Finally,the influence of mill modulus control gain on the vibration was analyzed numerically on the basis of the coupling dynamic model.Moreover,the agreement between the experimental results and the simulation results was confirmed and the measure reducing the mill modulus control gain was obtained to relieve mill vibration. 展开更多
关键词 Rolling mill vibration Coupling dynamic model Automatic gauge control Mill modulus control gain Vibration suppression
汽轮机转子振动故障诊断 认领
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作者 李志文 《中华纸业》 CAS 2020年第4期50-53,共4页
从原理上详细说明了如何通过设备故障诊断技术对公司汽轮机转子的振动故障进行准确的诊断,避免了故障的进一步恶化,并有效指导了汽轮机的维修工作。通过对汽轮机故障的准确诊断,充分体现了设备故障诊断技术在设备维护领域的重要作用。
关键词 汽轮机 设备故障诊断 谐波 振动 非线性振动
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金刚石圆锯片振动与噪声机理及其减振降噪技术研究综述 认领
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作者 田永军 孙爽 +1 位作者 张翔宇 段国林 《机械设计》 CSCD 北大核心 2020年第3期1-13,共13页
回顾了圆锯片振动与噪声领域的研究进展,探讨了金刚石圆锯片固有特性及锯切稳定性对锯片振动特性的影响等相关问题,综述了圆锯片气动噪声、锯切噪声产生机理;在减振降噪技术评述中,针对锯切参数优化技术、阻尼减振降噪技术、自适应控制... 回顾了圆锯片振动与噪声领域的研究进展,探讨了金刚石圆锯片固有特性及锯切稳定性对锯片振动特性的影响等相关问题,综述了圆锯片气动噪声、锯切噪声产生机理;在减振降噪技术评述中,针对锯切参数优化技术、阻尼减振降噪技术、自适应控制技术、锯片结构尺寸优化技术和基体拓扑优化技术及其机理进行详细的综述;最后,梳理了金刚石圆锯片振动与噪声研究领域中依旧存在的问题和可能的解决方案。 展开更多
关键词 金刚石圆锯片 振动 噪声 减振降噪
A novel none once per revolution blade tip timing based blade vibration parameters identification method 认领
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作者 Weimin WANG Xulong ZHANG +2 位作者 Dongfang HU Dengpeng ZHANG Paul ALLAIRE 《中国航空学报:英文版》 SCIE EI CAS CSCD 2020年第7期1953-1968,共16页
The vibration caused blade High Cycle Fatigue(HCF)is seriously affects the safety operation of turbomachinery especially for aero-engine.Thus,it is crucial important to identify the blade vibration parameters and then... The vibration caused blade High Cycle Fatigue(HCF)is seriously affects the safety operation of turbomachinery especially for aero-engine.Thus,it is crucial important to identify the blade vibration parameters and then evaluate the dynamic stress amplitude.Blade Tip Timing(BTT)method is one of the promising method to solve these problems.While,it need a high resolution Once Per Revolution(OPR)signal which is difficult to get for the aero-engine.Here,a Coupled Vibration Analysis(CVA)method for identifying blade vibration parameters by a none OPR BTT is proposed.The method assumes that every real blade has its own vibration performance at a given speed.Whereby,it can take any blade as the reference blade,and the other blades using the reference blade as the OPR for vibration displacement calculating and further parameter identifying.The proposed method is validated by numerical model.Also,experimental studies are carried out on a straight blade and a twisted three dimensional blade test rig as well as a large industrial axial compressor respectively.The results show that the proposed method can accurately identify the blade synchronous vibration parameters and quantitatively evaluate the mistuning in bladed disks,which lays a foundation for the reliability improvement of aero-engine. 展开更多
关键词 Blade tip timing Blade vibration Parameter identification Turbomachinery blades Vibration analysis
Research on Structural Design of Coal Crusher House in Thermal Power Plant 认领
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作者 Junhu Wang 《建筑环境与结构工程研究(英文)》 2020年第2期14-17,共4页
This paper takes the specific characteristics of pulverized coal room in thermal power plant as the starting point,firstly,this paper analyzes the process layout and structure selection,and then the structural design ... This paper takes the specific characteristics of pulverized coal room in thermal power plant as the starting point,firstly,this paper analyzes the process layout and structure selection,and then the structural design and vibration design requirements of coal crusher house are introduced in this paper.Finally,based on the engineering example,a new structure form of vibration isolation design is creatively proposed,which provides a new design idea for the practical engineering design. 展开更多
关键词 Coal-fired power plant Coal crusher house Vibration calculation Vibration isolation design
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航道水下爆破炸礁对周边建筑物的影响分析 认领
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作者 王丹 《黑龙江交通科技》 2020年第8期179-180,共2页
为研究水下炸礁过程中周边房屋的振动响应和爆破地震波的传播规律。以实际工程为依托,对爆破过程中的房屋采用现场实测并结合萨道夫斯基公式的方法进行了研究。结果表明:萨道夫斯基公式可较好的适用于本场地并能与现场实测振速结果相吻... 为研究水下炸礁过程中周边房屋的振动响应和爆破地震波的传播规律。以实际工程为依托,对爆破过程中的房屋采用现场实测并结合萨道夫斯基公式的方法进行了研究。结果表明:萨道夫斯基公式可较好的适用于本场地并能与现场实测振速结果相吻合;测点竖向方向上振速最大,随着时间的增加振速峰值也迅速降低;在距离房屋30~50 m之间时最大段药量不得超过2 kg,总药量不得超过20 kg。此次试验研究为实际工程提供一定意义的指导。 展开更多
关键词 爆破工程 航道 振动 振速
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