The Study of Force and the Mechanical Characteristic of Incremental Launching Construction Method on a Steel-Concrete Continuous Beam Bridge

The usage of steel-mixed composite beams is quite extensive today.During an event of constructing steel-mixed composite bridges,the incremental launching construction method is generally adopted.This paper mainly analyzes the force of incremental launching construction on a steel-concrete continuous beam bridge,the classification of incremental launching construction,the application of incremental launching construction in steel-mixed composite beams,the temporary facilities existing in incremental launching construction as well as their existing problems.Lastly,the analysis of the stress of composite beams in incremental launching construction is described by using the reference for the construction of mixed composite continuous beam bridges provided.

Electron Beam Desulfurization Project of Chengdu Cogeneration Power Plant Started Construction - A new cooperation in environment protection between China and Japan

On March 25 1996, the electron beam flue gas desulfurization demonstration project of Chengdu Cogeneration Power Plant started formal construction This is at present the largest electron beam desulfurization project in power plants in the world, and is jointly constructed by Sichuan Electric Power Bureau and the EBARA Works of Japan, This is an important cooperation project in environment protection between

Application of Mobile Formwork Cast-In-Situ Beam Technology in Bridge Construction

The application of mobile formwork cast-in-situ beam technology is conducive to providing quality assurance for bridge constructions.At the same time,it can improve the overall mechanization level of the construction process and further accelerate the construction progress,so as to shorten the construction period and improve the economic benefits of enterprises.In fact,this construction method has been widely applied.In order to assure a positive outcome from the use of this technology,this paper analyzes the application of mobile formwork cast-in-situ beam technology in bridge construction to provide reference.

Research on the Construction Characteristics of Stone-Built Folk Houses in Jiarong Tibetan Area <br/>—Take the Stone-Built Houses in Xisuo Village as an Example

The Jiarong Tibetan traditional residence is a characteristic regional architecture, located in a high-intensity, high-altitude and cold area, with geographic identification, and is a typical representative of this ethnic group. It has also become an important tourist destination and has important research value. The research used the methods of field survey surveying and mapping to conduct field survey and surveying on 20 buildings in Xisuo Village, a traditional village in the Jiarong Tibetan area. Measure building plans, elevations, and building sections, and collect measurement data for statistical analysis. The results show that the average total height of the building is 10.08 m, the average total building span is 12.44 m, the average total depth is 10.87 m, and the squareness is 0.87. The square shape of the building is more in line with the seismic requirements of high-intensity areas and the local terrain environment. The maximum window-wall ratio in the building is 0.18 south for the second floor, and 0.025 west for the first floor. Smaller window-to- wall ratios have better adaptability to high-altitude cold areas. The height of the building beam section is generally from 0.17 m to 0.32 m, and the average Beam span-depth ratio is 0.10. The building space construction has a good match with the properties of wood materials. These conclusions quantitatively analyze the characteristics of stone-built houses in high-intensity, high-altitude and cold areas, supplement the research on ethnic regional architecture, and provide materials and references for the design, repair and update of related buildings.

基于扩散模型的传像束光纤图像质量优化

为解决现有图像质量优化算法对于传像束光纤图像存在去模糊不彻底和轮廓细节恢复效果差的挑战,提出一种基于扩散模型的方法FBIDiff(fiber bundle image quality optimization via diffusion models)。设计两阶段网络使图像信息逐步恢复;引入扩散模型,使用残差策略学习图像轮廓信息;采用高低频分离思想,以解决图像中的轮廓等高频信息损失严重问题。实验结果表明,与现有算法相比,FBIDiff在结构相似性(structural similarity,SSIM)、学习感知图像块相似度(learned perceptual image patch similarity,LPIPS)和图像显著性变换值(differentiable image saliency transform,DISTS)指标上分别获得2.6%、6.1%和4.1%的提升,有效解决了高频信息损失严重和去模糊不彻底等问题。

BIM技术在预应力混凝土连续梁桥施工管控中的应用

针对大跨径预应力混凝土连续梁桥施工难以实现即时管控的现状,以某一大跨径预应力连续梁桥为例,融合BIM技术和有限元Midas Civil软件,建立参数化的BIM模型,实现对连续梁桥的4D施工模拟和施工状态监控。利用BIM中的Revit软件设计出工程信息非常完整的BIM模型,并进行过程的“碰撞检测”。通过Navisworks软件时间维度与参数模型关联,实现不同施工作业下的作业模拟和施工进程控制。通过将BIM模型与Midas Civil软件结合对梁桥施工关键节点位置和危险点进行施工状态和稳定性分析。将BIM技术应用于实际施工项目,能有效实现不同施工信息的交互和施工状态的实时监控,保证了施工质量和安全。

高速铁路连续梁桥施工与监测控制研究

为了保障高速铁路连续梁桥的施工质量和安全,本文深入研究了连续梁桥的施工与监测控制。首先,通过结构仿真,详细设计了结构参数,并进行了参数敏感性分析,特别关注了混凝土容重和弹性模量的影响。随后,探讨了施工控制策略,确保施工过程的精确性和稳定性。最后,基于测试截面与测点布置,计算了结构位移与应变,并分析了施工监测结果。本文提出了针对性的施工与监测控制方法,研究结果表明,这些方法能有效提升高速铁路连续梁桥的施工精度和安全性。

小半径高落差曲线钢箱梁落梁控制技术

顶推施工中的落梁是指在连续梁顶推到位,拆除导梁,将主梁顶起,拆除顶推时的临时滑道装置,然后将主梁均匀地降落并安放在永久支座上的过程。采用顶推法施工的桥梁,落梁控制是一个影响到全桥施工控制成败的关键环节。落梁时各支座处应当同步落梁,因为此时的梁体已是连续体系,如果主梁的竖向位移出现任何偏差,即各支座处落梁不同步,都将在梁内产生附加内力。因此,针对本项目曲线钢箱梁顶推完成后具有落梁高度大的特点,开展基于落梁不同步的控制研究,探究落梁不同步的限值,提出落梁控制指标,优化落梁施工方案。

基于实践的铁路桥梁预制混凝土板梁施工关键技术研究

为保证铁路桥梁预制混凝土板梁施工效果,研究以某地区铁路为例,分析了智能张拉施工技术在预制混凝土板梁施工中的应用效果。依据智能张拉施工技术原理和优势,在选择张拉施工设备后,完成智能张拉施工关键步骤施工,通过严格控制施工工艺和施工参数,保证了预制混凝土板梁施工质量。除此还对该技术的施工结果进行测试后检验,最后得出该技术可保证预制混凝土板梁施工质量,有效控制其发生变形,旨在实现提质降本增效的目标。

公路路基边坡锚杆格梁防护技术研究

文章以山东省某公路工程为例,通过边坡节理赤平投影分析了边坡稳定性,计算了三种工况下的边坡稳定性系数,并确定了锚杆格梁护坡的技术参数,最后应用有限元软件计算了增设锚杆格梁前后边坡的位移和剪应力分布。研究结果表明:边坡节理投影交点处于边坡投影弧的另外一侧,且位于软弱结构面的坡体内部,边坡部分岩体在极端气候或地震作用下会处于欠稳定状态;增设锚杆格梁护坡后,边坡受力得到较大改善,边坡下部位移和剪应力集中明显变小,边坡稳定性提高。

混凝土现浇梁与斜拉索综合线性内力监控技术

随着大跨度斜拉桥结构的广泛应用,其施工安全与精度控制愈发受到重视。该文围绕混凝土现浇梁与斜拉索的综合线性内力监控技术展开,旨在提高施工阶段的监控效率和精确度。通过设置详尽的监测点和采用高精度监测仪器,对主塔偏位、承台沉降和结构应力进行实时监测。预期通过实施系统的监控方案,能有效控制结构在施工过程中的偏移和变形,确保结构安全和施工质量。该研究强调精确监控在确保大跨度斜拉桥结构施工安全中的关键作用,为今后类似工程提供重要的技术参考。

高铁连续梁桥悬浇施工关键技术与控制技术研究

结合新建雄安新区至忻州高速铁路河北段小石坊村特大桥施工,阐述了高铁高墩预应力混凝土连续梁对称挂篮悬臂浇筑施工控制方法,并基于现场监控量测技术对主梁内力和变形进行控制,研究成果可为高速铁路连续桥梁悬浇施工控制提供借鉴。

基于施工工期控制的城郊高速公路大门架预应力盖梁设计优化分析

城郊高速公路建设环境复杂,存在诸多不确定因素。在多因素叠加下,可能会出现施工进度滞后的情况。为保证建设项目顺利通车,需要合理压缩各施工环节工期。作为城郊高速公路立交区广泛应用的结构形式之一,大门架预应力盖梁的施工工期对整个项目的进度有着重要影响。文章以某在建双向八车道高速公路大门架预应力盖梁为依托,分析了其在工期压缩下的优化设计方案。

钢管混凝土拱桥钢格子梁安装施工关键技术研究

以犍为岷江特大桥桥面系钢结构格子梁安装施工为例,介绍了钢管混凝土拱桥钢结构格子梁安装施工关键技术。钢管混凝土拱桥格子梁由钢结构纵梁、横梁通过栓焊结合方式拼装成型,与钢筋混凝土预制桥面板通过现浇钢筋混凝土方式组合为整体受力结构。钢结构格子梁作为桥面系受力、传力的关键结构,采用缆索吊装施工法,以及对称加载、栓焊结合连接、吊杆索力与桥面线形双重控制等方式安装。监测结果表明,钢格子梁安装施工质量控制效果较好。

斜撑贝雷梁组合支架研发及其在跨浅埋地铁现浇箱梁中的应用

高架结构在既有交通线路上方进行现浇梁施工时,将对线路的正常运行产生扰动,软土地质的存在将会进一步加剧此类影响。为解决类似技术难题,文章结合在建的上海松江高铁南站简支箱梁施工工程实例,设计一种可跨越既有交通线路直接施工的新型支架体系——斜向支撑体系与贝雷梁组合支架。结合支架部件组成及实际施工过程出现的荷载工况,通过MIDAS Civil有限元分析软件建模分析支架的应力及位移,确保支架在施工过程中的受力安全、结构稳定。结果表明,设计的斜撑贝雷梁支架结构,能在不影响既有线路运行的情况下进行施工,支架结构强度、刚度及稳定性均能满足规范要求,可为同类型桥梁的支架设计、计算提供可行性思路。

BEAM法地质预报系统在中国TBM施工中应用

TBM施工中,为了及时有效地探明前方地质条件,引进了国外IBM施工中已广为采用的BEAM探测法,并对在我国TBM工程中首次使用的情况进行了介绍。BEAM法以电法测试为基础,技术人员在TBM设备及洞壁上安装电极发射电流和进行观测处理,通过监视器实时评价和显示出前方地质情况的好坏。该方法的优势是可以进行实时观测和判断围岩情况,对TBM顺利及安全施工有很大的指导作用。在我国TBM施工中推广应用BEAM探测法具有很大的实际意义和价值。

Fatigue properties of special kind of reinforced concrete composite beams

The special reinforced concrete composite beam consists of a steel fiber reinforced self-stressing concrete composite layer and a reinforced concrete T-beam, and constructional bars are set up at their bonding interface. Fatigue properties of the composite beam under the action of negative moment were experimentally studied. Through inverted loading mode the load-beating state of a composite beam was simulated under the action of negative moment. With the ratios of constructional bars being 0, 0.082% and 0.164% respectively as parameters, the effects of constructional bars on the properties of composite beam, such as fatigue life, crack propagation, rigidity loss as well as damage behavior of bonding interface, were studied. The mechanism of the constructional bars on the fatigue properties of the composite beams and the restriction mechanism of crack widths and rigidity loss were analyzed. The test results show that the constructional bars can enhance the shear resistance of the bonding interface between composite layer and old concrete beam and restrict expanding of steel fiber reinforced self-stressing concrete, which are beneficial to synergistic action of composite layer and old concrete beam, to reducing the stress amplitude of bars and the crack width of composite layer, and to increasing the durability and fatigue life of the composite beam.

The Design and Analysis of Long-Span and Low-Depth Prestressed Composite Steel-Concrete Beam Bridge

The design scheme of long span and low depth composite steel concrete beams is introduced, and the methods of avoiding the cracking of concrete deck in the negative moment regions are proposed. Moreover, significant exploration for problems of the composite beams has been made, such as optimizing construction steps to regulate the stress, applying jacking technique to exert prestress on the concrete deck, investigating the uplifting force principle of the shear connectors by means of model test and non linear finite element analysis, and pointing out the countermeasure to reduce tension force of the shear connectors.

Application of Gaussian beam pre-stack depth migration in rugged seabed

Strong fluctuation of seabed,abrupt variation in depth and dip of seabed bring seismic imaging problems,such as irregular reflection waves,obvious multiple waves,serious lateral wave development,poor imaging on base surface and depression structure,low signal-to-noise ratio of middle and deep layers.In this paper,Gaussian beam migration imaging method is used to analyze the imaging effect of rugged seabed in deep water area,and the ray tracing method of wavefront construction method is used to analyze the kinematic characteristics of seismic waves.By improving the design of seismic data acquisition and observation system,imaging quality of fine structures is improved.

沁伊黄河大桥主梁施工方案研究

沁伊黄河大桥主桥采用85m+25×100m钢混组合梁,主梁采用整体槽型箱组合截面,主梁总高4.8m,桥面总宽16.56m。为了减少对河道的施工干扰,经综合比选,主桥施工时不在水中设置临时墩,采用无支墩顶推法施工。主梁采用多点自平衡分联顶推工艺,标准步距0.35m。钢主梁顶推到位后,分别对中支点和边支点设置20cm和25cm的预抬升,再按“皮尔格”法进行混凝土桥面板架设。计算结果表明,顶推过程中主梁各关键部位受力及稳定性均满足要求。