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关键词： Blasting  

摘要： Blasting-induced crack networks considerably impact the extent of rock fragmentation and the evaluative construction qualities of deep underground facilities. Based on the Hoek-Brown criterion, an integrated strategy of the Johnson-Holmquist (JH-2) model, failure criterion, and crack softening failure model was used to numerically explore the influences of borehole distance, time interval, and confining pressure on blasting crack propagation and coalescence. First, one-borehole blasting was used to reproduce the crack propagation results under free and non-reflecting boundaries, and the good results provided compelling evidence of the reliability of this strategy. For the two- and three-borehole blasting, it was discovered that high confining pressure paired with the large time interval was not favorable for crack coalescence. Therefore, simultaneous initiation is an optimal plan, which is not dependent on time interval and confining pressure. Simultaneously, if the borehole distance remains unvaried, the predominant influence on crack coalescence transitions from the time interval to the confining pressure as these two factors increase. Moreover, crack coalescence takes place when the tensile stress field of one crack is not converted into the compressive stress field of another crack, and crack coalescence has two key mechanisms: mutual and indirect modes. In addition, the dependence of controlling parameter on coalescence mode has been discussed. © The Chinese Society of Theoretical and Applied Mechanics and Springer-Verlag GmbH Germany, part of Springer Nature 2025.

关键词： 弯曲河道   局部溃决   溃坝洪水   数值模拟   曲率半径  

摘要： 为研究不对称局部溃决洪水在弯道中的变化规律,采用三维湍流模型计算了坝体左侧30%面积局部瞬溃后,洪水在六种曲率半径右弯河道中的演进特性。结果表明,溃坝洪水的演进呈现扩散、雍水、反射和波动四种特征。当大坝下游接长约为19.5倍坝前水深的右弯河道时,溃坝洪水出弯道,再经过15倍坝前水深距离后,水深便不再受弯道曲率的影响。弯道曲率对溃坝洪水流量过程及峰值流量几乎无影响,根据实验结果,拟合了弯道段与下游直段中峰值流量的经验公式。

关键词： 综合管廊   承插式接头   数值模拟   地震反应  

摘要： 采用有限元模拟方法,建立了考虑接头的综合管廊模型,分别对L型承插式接头和T型承插式接头在不同长度和不同伸出长度组合下的地震响应特性进行了分析。结果表明:L型承插式接头的伸出长度越长越不利于综合管廊抗震性能的提高,当其长度为0.2 m、伸出长度为0.1 m时,抗震性能最佳;T型承插式接头中,随着凸块长度和伸出长度增加,其水平相对位移减小,抗震性能提高,但切应力随之增大;综合比较发现,T型接头的尺寸增加更有利于提高综合管廊的稳定性。

关键词： 鱼道   小长宽比   潜孔式隔板   水力特性   数值模拟  

摘要： 文章通过改变潜孔的尺寸、相对位置以及隔板的布置形式,深入研究潜孔式隔板对小长宽比池室内水流结构的影响。研究发现:潜孔的宽度对池室的水流结构影响更加明显,其宽度的增加会显著提高其过流能力;潜孔位置处回流区是否“平衡”将直接影响其扩散情况,在“平衡”条件下,潜孔主流沿程基本不会与竖缝主流产生联动;异侧布置会明显丰富池室内的水流结构,进一步耗散彼此的能量,大幅弱化主流轨迹,降低鱼类的对上溯路径的感知。

关键词： 建筑物群   数值模拟   双线盾构隧道   结构安全   振动  

摘要： 临近隧道的地面建筑物施工以及地面荷载增加,可能会导致隧道周围土体应力重新分布,进而可能引发盾构隧道管片结构出现裂缝或渗漏水等问题,从而影响隧道的正常运营及结构安全。本文通过数值模拟分析了维龙供应链项目在不同施工阶段对狮子洋高铁隧道的影响,包括结构、内力及振动速度的变化情况。研究结果表明,在维龙供应链项目的各个施工阶段中,虽然狮子洋隧道的管片结构确实发生了位移和内力变化,但变化幅度小,均安全可控。因此,可以认为维龙供应链项目建设对狮子洋隧道的安全性影响有限。

关键词： 信息化技术   BIM技术   施工组织设计  

摘要： 为了研究基于信息化技术的施工组织设计与创新,优化施工管理,本文以某大型商业综合楼项目为例,通过对施工组织设计的介绍,分析了信息化技术对施工组织设计创新的影响,提出信息化技术在施工组织设计中的应用措施。研究结果表明,信息化技术的应用显著缩短了项目工期,降低了项目成本,提高了施工效率与资源利用率,为建筑行业在信息化时代的施工组织设计创新提供了有效参考。

关键词： 装配式建筑   剪力墙结构   竖向接缝   数值模拟  

摘要： 随着装配式建筑技术的不断发展,竖向接缝剪力墙作为一种重要的结构形式,在高层建筑和住宅建筑中的应用越来越广泛。为提高装配式建筑整体稳定性,通过建立不同接缝连接方式的剪力墙数值模型和试验模型,分析采用不同接缝形式剪力墙的抗震性能,研究结果表明:剪力墙接缝实测初始刚度值与模拟结果大致相同,表明了数值模拟的可靠性。且不同试件初始刚度和承载能均为试件A(强墙肢+弱连接)最小,试件C(预制剪力墙中深入锚固板)最大,表明将锚固板伸入剪力墙凹口处能够显著提升结构的受力性能。试件1、试件2、试件3的延性系数分别为2、1.93和1.83,极限荷载分别为400、450和500 kN,表明尽管在锚固板伸入剪力墙凹口处能够增强结构的整体性能,但在延性方面,弱连接加强墙肢形式的剪力墙较强。接缝形式为凹口处锚固板伸入剪力墙时的截面钢筋应变最大,即此连接方式下剪力墙受力性能最佳。

关键词： Reaction-diffusion model   Crystal plasticity   Dislocation cell structures   Strain localization   Irradiation hardening  

摘要： Accurately predicting the mechanical behavior of pure metals at different radiation doses and prescribing the microstructure evolutions, such as the dislocation structures, remain challenging. This work introduces a 3D hybrid numerical simulation scheme that integrates finite element (FE) and finite difference (FD) modules. The FE module is used to implement the crystal plasticity model, while the FD module is used to solve the reaction-diffusion model regarding dislocation nucleation and transportation. Our hybrid model successfully replicates the mechanical behavior of pristine Cu single crystals and provides details of dislocation cell structures that agree with the experimental observation. Furthermore, the model effectively reflects the irradiation hardening effects for Cu single crystals and demonstrates the formation of dislocation channels and shear band type of strain localization. Our work offers an effective approach for predicting the mechanical responses and the safety evaluation of pure metals in extreme working conditions.

关键词： Ultrasonic waves  

摘要： Phased array laser ultrasound with its high signal-to-noise ratio and flexible adjustment of specific modal ultrasonic propagation characteristics can be used for non-destructive testing of pipeline structures. Here, aiming at the defect detection problem of X80 pipeline, a theoretical model of array laser exciting multimode ultrasonic waves under thermal elastic mechanism was used to numerically simulate acoustic field distribution, propagation characteristics and interaction with defects of multimode laser ultrasonic waves in materials using finite element method. The results showed that phased array laser source has a significant enhancement effect on ultrasonic waves in specific direction compared to linear laser, it can effectively improve signal-to-noise ratio of detection signals;high-energy Rayleigh waves and high-energy transverse waves excited can be used to quantitatively detect surface cracks and internal defects in samples, respectively. Simulation results can provide a theoretical basis for further studying phased array laser ultrasonic detection. © 2025 Chinese Vibration Engineering Society. All rights reserved.

关键词： Large eddy simulation  

摘要： Large eddy simulation and FW-H acoustic analogy methods was used to investigate cavitation flow field and acoustic field characteristics of organ pipe nozzle, the study focused on evaluating their cavitation effect and effects of cleaning noise on cultivation of large yellow croaker. The flow field study results showed that compared with traditional scaled nozzles, organ tube nozzle has a more obvious turbulent boundary layer at nozzle throat due to effects of its natural vibration, which is conducive to generation of cavitation groups, the average cavitation volume generated by its operation can reach 1. 8 times that of scaled nozzles;in external flow field, organ pipe nozzle has characteristics of narrow jet trajectory and concentrated distribution of cavitation clouds;in near flow field area of 10 times the diameter of pipe, its cavitation performance is better than that of scaled nozzle. The cavitation sound field study results showed that the self-oscillating organ pipe nozzle has no obvious peak noise in large yellow croaker sound sensitive frequency band, its working noise is mainly high-frequency noise with frequency of above 2 000 Hz, and it exhibits a "maple leaf" directional distribution in downstream lateral plane;considering hearing curve of large yellow croakers, the total sound pressure level of organ pipe nozzle far-field monitoring point after weighting is more than 10 dB lower than that of scaled nozzle, its influencing range on large yellow croaker is limited to a zone with a radius of less than 0. 7 m, it is suitable for low-noise cleaning operations of large yellow croaker deep water aquaculture cages. © 2025 Chinese Vibration Engineering Society. All rights reserved.