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关键词： 深基坑   地铁隧道   数值模拟  

摘要： 以深圳市某明挖法深基坑为研究对象,基于三维数值模拟手段建立并行基坑-隧道相互作用模型,研究长距离、小间距并行深基坑施工对地铁区间结构的影响。模拟结果表明,本工程基坑开挖过程中,受地层应力重分布影响,运营地铁隧道结构最大水平位移为为3.88mm,最大竖向位移为2.21mm,均低于深圳地区地下结构5mm的变形警戒阈值。对比地铁区间隧道水平和竖向位移,随基坑开挖,变形趋势逐渐增大,且随着区间隧道逐渐远离基坑,变形逐渐收敛。但隧道埋深对竖向位移变化有着较大影响,当开挖深度大于隧道埋深时,基坑开挖施工对区间隧道竖向变形的影响显著增大。研究成果可为今后该地开展类似项目的设计优化和施工控制提供科学依据和工程借鉴。

摘要： 《中国科技术语》创刊于1998年,由中国科学院主管、全国科学技术名词审定委员会主办。现为双月刊,逢单月初出版。设有理论研究、标准规范、定名研讨、科技翻译、数据技术、实践应用、术语溯源、专家访谈、术语辨析、科学语言、热词新词等栏目。为进一步服务科技名词规范化标准化事业,促进科技名词在各个行业的规范应用,现面向科技界、翻译界、语言学界、编辑出版界发起征稿活动。我们诚挚邀请您围绕以下栏目贡献您的智慧与洞见。

关键词： 信息化服务   科学数据   数据集   科技论文   出版服务  

摘要： 为顺应大数据时代的发展需要,《中国科技术语》开展科学数据出版服务,为作者和读者提供集文献和数据于一体的信息化服务。本刊的数据出版分为2种模式:(1)科技论文附加数据:本刊鼓励作者在提交科技论文时,附加支撑数据集,在文中对相关数据集进行描述和管理,为使用者在阅读论文的同时提供科学数据的访问引用、分析等。

关键词： Transfer functions  

摘要： To evaluate the influence of metro induced vibration on precision instruments in auniversity laboratory of a measured transfer function formulation was proposed to predict the vibration responses on the ground surface and in the building. Firstly, the frequency-domain excitation forces acting on the tunnel structure were determined by using a coupled train-track model, then the transfer functions between excitation and receiver points in the station-soil-building system were measured by a field hammer experiment in the station, and finally the vibration responses were obtained by the transfer function formulation. Based on this formulation, the vibration responses for the general non-ballast track and steel spring floating slab track were predicted and compared with the field measured data under the metro operation. The results show that the transfer functions obtained through field measurements accurately reflect the vibration propagation characteristics of the tunnel/station-soil-building system, indicating that the proposed formulation has good prediction accuracy. © 2025 Chinese Vibration Engineering Society. All rights reserved.

关键词： Curve fitting  

摘要： Track irregularities significantly impair the safety and stability of vehicle operation. Identifying the sensitive wavelengths of medium- and long-wavelength track irregularities and establishing corresponding management limits for metro lines hold significant reference value for line maintenance. A rigid-flexible coupled dynamic model of a metro vehicle is established that takes into account the flexibility of the carbody. The model is then validated using measured carbody accelerations. Multi-cosine waves are used to model longitudinal-level, alignment, cross-level, and gauge irregularities. The influence of different wavelengths and amplitudes of these irregularities on vehicle dynamic performance is investigated and the range of sensitive wavelengths of track irregularities is determined. Finally, the simulation results are extrapolated to the management value of each dynamic performance index using curve fitting, and three levels of management limits for track irregularity amplitude are proposed. The results show that the sensitive wavelengths of metro track irregularities are mainly affected by vehicle suspension modes, car body flexibility modes, and bogie hunting motions. The four types of track irregularities that should be prioritized in the control of the wave band, together with their minimum amplitude limits, are as follows: longitudinal-level (1.5 ∼ 4 m and 6 ∼ 10 m, with minimum limits of 2.4 mm and 4.7 mm, respectively);alignment (10 ∼ 30 m, with a minimum limit of 1.6 mm);cross-level (1.5 ∼ 4 m and 6 ∼ 22 m, with minimum limits of 0.8 mm and 5.2 mm, respectively);gauge (10 ∼ 15 m, with a minimum limit of 5 mm). © 2025 Chinese Vibration Engineering Society. All rights reserved.

关键词： Sensitivity analysis  

摘要： Subway spatial route shape significantly affects rail wear. If effects of spatial route shape on rail wear can be considered during the route selection stage to optimize route plan, rail wear can be reduced at source. However, feasible route schemes have infinitely many, and a large number of schemes need to be designed for comparative analysis during route selection stage. The existing mode to establish simulation model and then calculate rail wear can consume a lot of time to significantly affect design efficiency, and long calculation time is difficult to accept. Here, an artificial neural network was introduced to explore correlation between subway spatial route shape and rail wear, and realize efficient and accurate prediction of rail wear under different subway spatial route shapes. Firstly, a rail wear calculation model was established based on the prototype of subway A-type car, and effects of different spatial route shapes, parameters on wears of inner and outer rails were analyzed, and sample datasets were established. Furthermore, based on the analysis results, a neural network model was established to predict rail wear considering circular curve radius, circular curve length, transition curve length, slope, slope algebraic difference and superelevation, and a model structure optimization method based on Sobol analysis was proposed. Finally, through sample data training, a mapping relation between subway spatial route shape and rail wear was established. The study results showed that for inner and outer rails, the same route shape parameters have different effects;for inner rail wear, the main affecting parameters are transition curve length, circular curve radius and superelevation;for outer rail wear, circular curve radius is the main affecting parameter, and its affecting degree is much higher than other parameters;rail wear can be correctly predicted according to subway spatial route shape parameters, and prediction accuracies of inner and outer rail

关键词： 幼小衔接   项目式学习   主动学习  

摘要： 幼儿园项目式学习是一种以问题为导向的探究式学习模式,旨在帮助幼儿通过探究真实的、具有挑战性的问题获得关键的经验和能力。其中,驱动性问题起着至关重要的作用,它能够将枯燥的知识与生动的实践相结合,激发幼儿主动学习的兴趣,促进幼儿主动学习。在“地铁来了”这一中班建构项目活动中,幼儿通过以问题为驱动的学习方式,对感兴趣的真实问题进行探究,从而在解决问题的过程中实现主动学习。