Application Strategies of Shotcrete Anchor Support Technology in Highway Bridge and Tunnel Engineering

This article analyzes the application strategies of shotcrete anchor support technology using a highway bridge-tunnel construction project as an example.The article covers various strategies,including support plan formulation,mortar shotcrete anchor construction,grid steel frame construction,steel mesh construction,and concrete support construction.This analysis aims to provide a guideline for those interested in applying this technology and improving the quality and safety of highway bridges and tunnels construction.

Discussion on Construction Technology of Subway Tunnel Expansion under Bridge Foundation

As the urban populations grow,the number and size of subway construction projects are increasing while also meeting higher construction standards.So,subway construction projects must have a better understanding of construction technology.This article focuses on the construction technology of the subway tunnel expansion under the bridge foundation.By analyzing the engineering characteristics of the bridge foundation and using a project as an example,this article provides a detailed discussion of the construction process of tunnel expansion under a bridge foundation.This article aims to serve as a reference for subway tunnel construction in China to ensure the key points of construction technology are understood,thus improving construction quality and laying a solid technical foundation for the sustainable development of urban rail engineering.

Construction Technology of Pile Foundation for Subway Tunnel Crossing Bridge

Urban infrastructure has become more complex with the rapid development of urban transportation networks.In urban environments with limited space,construction of facilities like subways and bridges may mutually influence each other,especially when subway construction requires passing under bridges.In such cases,pile foundation replacement technology is often necessary.However,this technology is highly specialized,with a lengthy and risky construction period,and high costs.Personnel must be proficient in key technical aspects to ensure construction quality.This article discusses the technical principle,construction process,and core technology of pile foundation replacement,along with the application of this technology in subway tunnel crossing bridge projects,supported by engineering examples for reference.

Wind tunnel tests on aerodynamic characteristics of vehicles on same-storey highway and rail bridge under crosswind

In recent years,the safety and comfort of road vehicles driving on bridges under crosswinds have attracted more attention due to frequent occurrences of wind-induced disasters.This study focuses on a container truck and CRH2 high-speed train as research targets.Wind tunnel experiments are performed to investigate shielding effects of trains on aerodynamic characteristics of trucks.The results show that aerodynamic interference between trains and trucks varies with positions of trains(upstream,downstream)and trucks(upwind,downwind)and numbers of trains.To summarize,whether the train is upstream or downstream of tracks has basically no effect on aerodynamic forces,other than moments,of a truck driving on windward sides of bridges(upwind).In contrast,the presence of trains on the bridge deck has a significant impact on aerodynamic characteristics of a truck driving on leeward sides(downwind)at the same time.The best shielding effect on lateral forces of trucks occurs when the train is located downstream of tracks.Finally,the pressure measuring system shows that only lift forces on trains are affected by trucks,while other forces and moments are primarily affected by adjacent trains.

The Application of High Performance Concrete in Highway Bridge in Cold and Arid Regions

High performance concrete originated in the generation of high strength concrete, and it is a new high technology of concrete, is in common with high quality and in concrete. High durability on the perspective of improvement and become, use a lot of high quality raw materials and modern technology, is the main development direction of concrete. Because its comprehensive performance by the superiority of the focus of the society, the strict construction technology in the extensive application in the highway bridge, high performance can the use of concrete can improve the efficiency of its safety and avoid unnecessary accidents

高架桥梁和盾构隧道的相互影响研究

根据江阴滨江路快速化改造及江阴靖江长江隧道工程现场实际施工工序,在桥墩桩基部分完成情况下,隧道左线穿越高架节点,在隧道左线建成工况下完成桥梁剩余桩基及满堂支架上部结构施工,在桥梁完成施工后,隧道右线穿越高架桥梁节点。论文通过Plaxis3D模型分析了盾构隧道施工对已建桥梁的影响,提出施工方案优化及监测等保障措施以确保桥梁施工过程中的隧道绝对安全。

Study on the influence of skid resistance on traffic safety of highway with a high ratio of bridges and tunnels

The safety of highways with a high ratio of bridges and tunnels is related to multiple factors,for example,the skid resistance of the pavement surface.In this study,the distribution of accidents under different conditions was calculated to investigate the relationship between the road skid resistance and the incidence of traffic accidents based on the traffic accident data of the Yuxiang highway.Statistical results show that weather conditions and road alignment may affect traffic accidents.The correlation analysis method was used to study the relationship between three factors and traffic accidents.The results show that road alignment,weather conditions and road skid resistance are related to the incidence of traffic accidents.The traffic accident prediction models were established based on back propagation neural network to verify the correlation analysis results.It is confirmed that road alignment,weather conditions and road skid resistance are the factors that affect traffic accidents.

三塔四跨悬索桥施工阶段颤振性能研究

为了解双主跨悬索桥加劲梁吊装期间颤振稳定性,以跨度为(230+800+800+348)m三塔四跨悬索桥为背景,分析该桥加劲梁吊装期间的颤振性能。建立该桥不同吊装阶段三维有限元模型,分析竖弯、扭转模态特性,采用理想平板颤振临界风速理论公式计算桥梁不同吊装阶段及各模态组合下的颤振临界风速,以确定最不利吊装阶段及模态组合;基于此,设计节段模型风洞试验测试原断面及上桥面中央增设竖向稳定板断面桥梁颤振临界风速。结果表明:三塔四跨悬索桥施工阶段的模态特性复杂,颤振分析时模态组合需考虑两主跨间的振动关系;该桥吊装率为8.5%和19.8%时,颤振临界状态由以北侧主跨振动为主的扭弯模态组合确定,吊装率≥29.3%时,颤振临界状态由以南侧主跨振动为主的扭弯模态组合确定,最不利吊装率为40.8%;该桥加劲梁原断面的颤振性能较差,在上桥面中央增设竖向稳定板可以有效提升桥梁的颤振临界风速。

斜风作用下超大跨跨海斜拉桥典型施工状态抖振响应研究

为研究风偏角和风速对超大跨跨海斜拉桥典型施工状态抖振性能的影响,以黄茅海大桥为背景,通过气弹模型风洞试验对斜风作用下该桥边塔最大单悬臂、中塔最大双悬臂、边塔最大双悬臂3种典型施工状态的抖振响应进行分析,并对基于气弹模型风洞试验和《公路桥梁抗风设计规范》(JTG/T 3360-01—2018)的等效静阵风荷载进行对比。结果表明:超大跨跨海斜拉桥各典型施工状态抖振响应最不利风偏角为0°~30°,各典型施工状态在各风偏角下的抖振响应与风速呈二次函数关系;各典型施工状态下竖向抖振响应主要由主梁一阶对称竖弯模态贡献,横向和扭转抖振响应主要由桥塔一阶横弯模态贡献;与基于气弹模型风洞试验的等效静阵风荷载相比,基于规范计算的等效静阵风荷载偏不安全,建议进一步研究超大跨跨海斜拉桥的等效静阵风荷载。

超大跨多塔跨海斜拉桥施工期抖振响应分析与控制技术研究

超大跨多塔跨海斜拉桥悬臂施工阶段,相对于成桥状态具有刚度小、自振频率小和阻尼比低的特点,在沿海高设计风速作用下容易产生较大的抖振响应。准确地计算桥梁施工期抖振响应有利于提高桥梁建设的安全性。为了实现桥梁抖振响应的精细化计算,以黄茅海大桥为工程背景,将分离式双箱梁的三维导纳考虑进抖振频域计算方法,通过最大双臂状态气弹模型风洞试验验证该计算方法相对于传统的定常假设和Sears函数具有更高的准确性。然后基于该计算方法探寻了超大跨度多塔跨海斜拉桥施工期抖振响应的发展规律:在0~200 m悬臂范围内悬臂端的抖振竖向和横向位移极值对施工悬臂端长度不敏感,而悬臂长度一旦超过200 m后抖振竖向和横向位移极值则对悬臂端长度非常敏感,呈现指数增长,最大抖振竖向位移极值可以达到4.9 m;悬臂端抖振扭转位移极值与悬臂端长度基本呈线性关系。分析抖振响应频响函数,提出了利用模态分析进行临时墩布置位置初步设计的理念,通过抖振精细化计算方法计算9种临时墩布置位置下的桥梁抖振响应,并进行了其中推荐方案的风洞试验验证了该理念的可行性。结果显示:临时墩的布置最多可以降低75%的悬臂端抖振竖向位移极值;需要综合考虑在悬臂施工过程中悬臂端的抖振位移极值随着跨度的增长而增长,临时墩布置在离桥塔2/3最大悬臂长度处最为合理。

金仁桐高速公路桐梓河大桥隧道锚散索鞍安装方案研究

悬索桥锚碇作为大桥的重要受力结构,其结构形式多样,可因地制宜进行设计,西部陡峭山区峡谷多设计为隧道锚。由于散索鞍顺应索股倾斜入锚的特殊结构特点,普遍采取倾斜布置在隧道锚锚室内,根据散索鞍形状和质量、施工环境条件等因素,通常可采取大吨位起重机直接吊装、布设滑道滑移安装、门架吊装等安装工艺。依托贵州金仁桐高速公路桐梓河大桥工程,针对高山峡谷区该大跨度悬索桥工程隧道锚结构设计特点,介绍了散索鞍安装总体方案,以及散索鞍安装滑移支架系统设计方案,支架滑移法在仁怀岸大倾角隧道锚内吊装散索鞍施工工艺。

隧道工程公路桥梁隧道工程开挖防护施工技术研究

随着交通基础设施建设的不断推进,公路桥梁隧道工程在交通网络中的地位日益凸显。作为连接地面与地下、水域与陆地的关键枢纽,隧道工程不仅承载着重要的交通流量,还直接关系到交通安全、运行效率以及使用寿命。因此,加强隧道工程的施工质量控制尤为重要。在施工过程中,要确保施工安全,采用先进的开挖技术和防护措施,有效降低施工过程中的安全风险,减少事故发生的可能性。同时,合理的开挖方案和管理标准还能提高施工效率,缩短工期,降低工程成本。

盾构区间隧道侧穿桥梁施工稳定性分析

当盾构区间隧道侧穿桥梁时,施工会引起较大的地表沉降和应力变化,加大施工过程的风险,并对项目自身及沿线桥梁的安全性产生一定的影响。以青岛某地铁某线路盾构隧道侧穿桥梁为背景,通过建立盾构侧穿桥梁施工的三维有限元模型,评估侧穿桥梁过程中施工的稳定性,结合盾构侧穿桥梁的施工工艺,对土体位移、管片变形、桥墩及桥桩的规律进行研究。结果表明,在双线隧道开挖的过程中,地表、管片、桥墩及桥桩的竖向位移与水平位移数值均较小,均满足施工规范要求。研究结果可为类似盾构侧穿桥梁的施工提供参考。

上海轨道交通市域线下穿桥梁桩基托换施工技术与监测

依托上海轨道交通市域线机场联络线工程JCXSG-13标南回转匝道托换工程,为确保受力转换过程中桥梁结构安全,结合对既有桥梁结构形式、现场周边环境以及监测数据的分析,详细对桥梁桩基托换施工过程中施工技术、监测内容、监测数据、测点布置进行了研究,对监测结果进行对比分析。施工监测结果表明,所采用桩基托换设计、施工方案可行,桩基托换过程中未发现肉眼可观测的裂缝发生,混凝土梁竖向变形、主纵梁挠度以及钢立柱水平竖向位移基本设在控制值范围内,顶升过程中结构受力稳定、沉降在可控设计范围内,最后给出相关桩基托换设计和施工建议,可为类似工程提供借鉴。

高速公路互通地道桥工程中的回旋钻施工技术探讨

高速公路作为不同地区经济、文化联通的桥梁,是我国陆地交通体系的重要组成部分。保证高速公路工程施工质量对推动当地经济发展、解决民生问题有着重要意义。在路桥工程施工中,路基强化是极其重要的施工环节,虽然钻孔灌注桩施工技术日益成熟,但如果施工工艺选择不合理,依然会影响整体施工质量和工程进度。基于此,结合某高速公路互通地道桥工程案例,探究回旋钻施工技术应用措施,同时分析施工技术的应用难点,并提出相应的解决措施,旨在保障钻孔灌注桩整体的施工质量水平、提高路基工程使用安全性能、保障高速公路工程的综合建设效益。

在建隧道对既有桥桩影响研究

基于某在建隧道工程,首先采用Midas有限元软件建立了隧道和既有桥桩的三维数值模型;其次通过对计算值和实测值进行对比,验证了数值模型参数选取的合理性;最后从隧道埋深H、隧-桩间距S以及竖向荷载N3个因素深入讨论了隧道施工对既有桥桩的影响。研究结果表明:隧道埋深H、隧-桩间距S导致隧道施工对既有桥桩有很大的影响,竖向荷载N导致隧道施工对既有桥桩的影响不大;并且邻近在建隧道的桩能够起到很好的隔离作用,减小隧道施工对远离隧道的桩的影响。

高速公路隧道与桥梁加固技术和施工工艺研究

研究了高速公路隧道与桥梁工程的加固技术和施工工艺,在明确影响隧道和桥梁稳定性主要因素的基础上,分析了混凝土裂缝修复技术、钢筋保护防锈处理技术、增大结构截面加固技术、粘贴钢板加固技术、粘贴碳纤维加固技术、预应力碳纤维板加固技术。

隧道位置对原有邻近桥梁桩基的影响分析

为了分析隧道位置对邻近桥梁桩基的影响,论文采用了三维有限元软件对盾构隧道施工过程进行数值分析。结果显示,隧道和桩基之间的水平距离越大,桩基受到的影响越小;当隧道埋深越大时,隧道施工对桥梁桩基的影响越小。

盾构近接施工对桥桩沉降影响分析及保护措施

以地铁盾构隧道近接侧穿既有桥桩工程为背景,基于现场实测数据,对盾构近接侧穿施工全过程中桥桩沉降的变化规律、各阶段的沉降占比、隧道洞身软弱地层分布和袖阀管打设方式对桥桩沉降的影响进行分析。分析结果表明:软弱地层中盾构近接侧穿桥桩时,桥桩竖向位移整体呈“先小幅上升,后下沉”的变化规律;桥桩沉降主要发生在盾构通过期间及通过后一周,约占总沉降的80%~90%;当隧道与桥桩平面净距小于2D时,对临近隧道的桥桩采取桩周全包袖阀管预注浆加固措施,可有效降低盾构施工对桥桩沉降的影响;隧道洞身范围软弱土层分布比例越高,桥桩沉降越大;桩周袖阀管注浆孔应优先考虑垂直打设,避免注浆盲区,以保证土体加固及桥桩沉降控制效果。

桥隧工程建设中的环境问题分析与探讨

本文围绕桥梁和隧道建设中的环境问题进行分析和探讨展开。首先介绍了桥梁和隧道的结构设计原则和方法,以及材料选择的考虑因素,并比较了不同结构类型的优缺点。此外,本文讨论了工程的建设过程和维护管理策略,包括质量控制、安全管理和环境保护等问题。最后,探讨了桥梁和隧道建设领域的技术创新和挑战,介绍了最新的工程技术和创新,以及环境保护和可持续发展的建议。通过本文的研究,为桥梁和隧道的设计与建设提供有益的参考和指导。