Subjects: Civil Engineering and Building Construction >> Civil Construction Structures submitted time 2023-11-11
Abstract: This report summaries the current status about the design of the structures rigidly connected with weak sky corridor, followed by studying in details the theoretical issues involved in the structural analysis associated with the estimation of torsion performance of the connected structures and cracking and stiffness deterioration of the connecting slabs, which are concerned by structural engineers.
In this report, taking deformation characteristics of the weak connecting slab as a key point, the basic principles of damage mechanics are applied to conduct a detailed and in-depth study on the stress redistribution between the concrete and steel, as well as between the concrete slab and supporting steel gird due to the damage evolution and deterioration of elastic modulus of the damaged concrete. Adopting the contrary thinking according to phenomenology, a suggestion of reducing the elastic stiffness including the flexural, shear and axial stiffness as the effective stiffness by the macroscopic stiffness reduction factor R is put forward, to reflect the microscopic concrete damage effects. Thus, a practical design method is proposed, by using the equivalent elastic time history analysis of a 3D model, in which each tower has its own rigid diaphragm and the connecting slab is flexible with reduced stiffness to effectively realize the above-mentioned stress redistribution.
Through a typical engineering example of the weak slab with reduced effective stiffness of the sky corridor connecting structures presented here, the report authors’ energy and ductility-based concept of the seismic design is elaborated in detail. The results of the equivalent elastic time history analysis of the example show that it is unreasonable to completely neglect the concrete contribution to the structural system combined with the reinforced concrete connecting slab and the steel truss, verify the effectiveness of the above practical design method which adopts the equivalent elastic time history analysis to assess the torsional performance of the connected structures and realize the redistribution of the internal forces due to the stiffness deterioration of the reinforced concrete connecting slab, which results in a substantial reduction in the steel quantity of the connecting truss.
In response to the phenomenon of assigning "zero stiffness" to connecting slab, which is widely adopted currently in design, the theoretical insights and recommendations in this report are inspirational and realistic meaningful to improve the design method as well as economic and technical indicators.
Peer Review Status:Awaiting Review
Subjects: Civil Engineering and Building Construction >> Building Materials submitted time 2021-09-25
Abstract: " The waste rice husk ash produced by the biomass power plant was added to the concrete instead of part of the cement to prepare a new type of electric power plant-rice husk ash (E-RHA-C) concrete (E-RHA-C). ), the mechanical properties of E-RHA-C and the durability test of 210d Na2SO4 erosion and 105 cycles of dry and wet Na2SO4 solution were carried out. Combined with its macro-mechanical and physical parameters and micro-morphology, the mechanical strength and sulfate resistance of E-RHA reinforced concrete were tested. The mechanism of erosion ability is analyzed, and the durability of E-RHA-C is evaluated by the energy conversion method, and the corresponding constitutive model is obtained. The results show that: ordinary concrete mixed with a proper amount of rice husk ash mineral admixture can effectively improve the mechanical properties, but the stability of the concrete mechanical properties increases gradually decreases. As the sulfate age increases, the E-RHA-C specimens gradually peel off locally and expand in volume; the mechanical properties and relative dynamic elastic modulus first increase and then drop sharply, and the effective porosity first decreases and then increases. E-RHA-C bone The damage degree of the interface zone around the material is much smaller than that of ordinary concrete, which shows better corrosion resistance. The enhancement of the mechanical properties of the specimens in the early stage of E-RHA-C by sulfate attack is mainly manifested in the increase of total strain energy and dissipation energy, and the increase of E-RHA-C plasticity and ductility deformation. In the second stage, E-RHA-C gradually manifests the peak stress and ductility reduction, and the obvious phenomenon of brittle failure. Based on statistical damage theory and dissipated energy, a constitutive model of durability damage of E-RHA-C is established.
Peer Review Status:Awaiting Review
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2020-10-16
Abstract: A triangular plate-bending element with a new multi-resolution analysis (MRA) is proposed and a novel multiresolution element method is hence presented. The MRA framework is formulated out of a displacement subspace sequence whose basis functions are built out of scaling and shifting on the element domain of basic full node shape function. The basic full node shape function is constructed by means of extending the shape function triangle domain for a split node at the zero coordinates to the hexagon area enclosing the zero coordinates. As a result, a new split-full node notion is presented and a novel rational MRA concept together with the resolution level (RL) is constituted for the element. Via practical examples, it is found that the traditional triangular plate element and method is a mono-resolution one and also a special case of the proposed element and method. The meshing for the monoresolution plate element model is based on the empiricism while the RL adjusting for the multiresolution is laid on the rigorous mathematical basis. The analysis clarity of a plate structure is actually determined by the RL, not by the mesh. Thus, the accuracy of a plate structural analysis is replaced by the clarity, the irrational MRA by the rational and the mesh model by the RL that is the discretized model by the integrated. The continuous full node shape function unveils secrets behind assembling artificially of node-related items in global matrix formation by the conventional FEM." " " "
Peer Review Status:Awaiting Review
Subjects: Civil Engineering and Building Construction >> Civil Construction Engineering submitted time 2020-01-08
Abstract: "
Peer Review Status:Awaiting Review
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:近年来,动态施工工艺展示技术在工程实践中发挥了日益重要的辅助建造作用。针对动态施工工艺创建技术门槛较高、集成管理难度大、复用程度低的技术现状。本文从多源数据参数共享的角度,实现了动态施工工艺的快速、精准创建。同时,结合软件工程学的方法,研发了基于BIM技术的施工工艺管理平台,实现了动态施工工艺的企业级的集中创建和集成管理,有效助力了现场管理。工程实践显示:基于BIM技术的施工工艺管理平台能够实现施工工艺的集成管理和广泛复用,具有极好的应用前景。
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:合川渠江景观大桥采用主跨400m的单主缆地锚式悬索桥,桥塔曲面造型复杂,主梁为变宽分离式扁平钢箱梁,为提高设计效率、保证设计质量,提出“R+GH+R”的BIM协同设计平台。借助二次开发实现不同软件平台间的信息交互,内置制模标准及构件编码体系,应用BIM技术进行全桥设计。在设计过程中,采用参数化批量建模、实时渲染、智慧出图、虚拟现实、3D打印及4D施工模型等技术,提升了设计质量和工作效率,同时也为桥梁三维设计的发展和应用实践积累经验。
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:近年来,动态施工工艺展示技术在工程实践中发挥了日益重要的辅助建造作用。针对动态施工工艺创建技术门槛较高、集成管理难度大、复用程度低的技术现状。本文从多源数据参数共享的角度,实现了动态施工工艺的快速、精准创建。同时,结合软件工程学的方法,研发了基于BIM技术的施工工艺管理平台,实现了动态施工工艺的企业级的集中创建和集成管理,有效助力了现场管理。工程实践显示:基于BIM技术的施工工艺管理平台能够实现施工工艺的集成管理和广泛复用,具有极好的应用前景。
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:实景建模;倾斜摄影;全生命周期;隧道检测
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:合川渠江景观大桥采用主跨400m的单主缆地锚式悬索桥,桥塔曲面造型复杂,主梁为变宽分离式扁平钢箱梁,为提高设计效率、保证设计质量,提出“R+GH+R”的BIM协同设计平台。借助二次开发实现不同软件平台间的信息交互,内置制模标准及构件编码体系,应用BIM技术进行全桥设计。在设计过程中,采用参数化批量建模、实时渲染、智慧出图、虚拟现实、3D打印及4D施工模型等技术,提升了设计质量和工作效率,同时也为桥梁三维设计的发展和应用实践积累经验。
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:本文研究了基于BIM的大型钢结构虚拟施工仿真系统并应用于实际工程之中。大型钢结构施工具有环境因素复杂、操作要求高、安全隐患多等特点,且难以周全考虑。针对这些难点,Unity3d和BIM结合的虚拟施工仿真系统,能够充分利用并可视化工程设计信息,逼真的展现不同情境下的施工现场,可用于施工现场管理和技术交底,全面排查各种质量安全隐患。该系统在杭州上城区体育中心大跨度钢桁架施工中的成功应用,大大提高了施工效率,充分保障了施工过程中的质量与安全。
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:为改进目前预制装配式建筑预制率手工计算存在效率低下、误差加大的问题,本研究利用建筑信息模型BIM技术,通过对Revit软件的二次开发,实现了对基于BIM模型的预制装配式混凝土建筑(Precast Concrete,简称PC)预制构件工程量的自动统计和预制率的自动计算,验证了基于Revit平台计算PC建筑预制率的可行性。利用本文的二次开发成果,通过不同构件预制率的动态选择组合,可以估算建设成本,进而选择成本可接受范围内的预制方案,增加经济效益,为决策者制定预制方案提供决策依据。
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:实景建模;倾斜摄影;全生命周期;隧道检测
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:本文研究了基于BIM的大型钢结构虚拟施工仿真系统并应用于实际工程之中。大型钢结构施工具有环境因素复杂、操作要求高、安全隐患多等特点,且难以周全考虑。针对这些难点,Unity3d和BIM结合的虚拟施工仿真系统,能够充分利用并可视化工程设计信息,逼真的展现不同情境下的施工现场,可用于施工现场管理和技术交底,全面排查各种质量安全隐患。该系统在杭州上城区体育中心大跨度钢桁架施工中的成功应用,大大提高了施工效率,充分保障了施工过程中的质量与安全。
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:本研究从铁路路基健康监测出发,基于FDM(Fused Deposition Modeling)与FBG(Fiber Bragg Grating)技术开发了路基小变形监测系统。利用FDM技术和FBG传感技术设计带封装和锚固板的FBG传感器监测模型,标定试验可得荷载与土体位移的关系,结果表明:位移与荷载呈良好的线性关系,相关系数达到0.99,标试验测得最大位移为0.25 mm,最小位移为0.05 mm,传感器灵敏度达到4 nm/mm,最小分辨率达到0.62 µm。通过两种试验工况检验传感器可行性,包括监测路基在静、动载作用下的位移变化,静荷载作用下监测数据表明:波长及位移随时间呈阶梯性增长,试验成功采集路基的最小位移达到0.004 mm。动荷载监测试验结果表明传感器可以快速反映车辆模型荷载产生的竖向压力。
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:目前的BIM应用与各种新兴信息技术相结合,在多领域均有其身影,而铁路四电工程因其多专业交叉、施工难、跨自然区域大等特点,迫切地需要BIM来提高设计、施工的效率。为使BIM在铁路四电工程中更好地应用
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:为改进目前预制装配式建筑预制率手工计算存在效率低下、误差加大的问题,本研究利用建筑信息模型BIM技术,通过对Revit软件的二次开发,实现了对基于BIM模型的预制装配式混凝土建筑(Precast Concrete,简称PC)预制构件工程量的自动统计和预制率的自动计算,验证了基于Revit平台计算PC建筑预制率的可行性。利用本文的二次开发成果,通过不同构件预制率的动态选择组合,可以估算建设成本,进而选择成本可接受范围内的预制方案,增加经济效益,为决策者制定预制方案提供决策依据。
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:广西荔浦至玉林高速公路是国家高速公路网G59的重要组成部分,项目建成之后将完善中国国家高速公路网,促进北部湾经济向北部延伸,提高南北通道通行能力。项目具有规模和空间距离大、地质和地理环境复杂、涉及的区域规划协调关系较多、控制性工程技术复杂等难点。项目方案设计阶段采用Infraworks作为核心平台,勘查设计阶段采用MicroStation作为核心平台,通过多软件的应用,将道路、桥梁、建筑等数据导入到核心平台中,实现多源数据融合。通过利用BIM技术的综合优势逐一解决项目中存在的难点问题,实现从场地勘测到BIM协同设计、再到施工管理全过程的BIM集成应用,并且在施工阶段自主研发了基于设计BIM模型的施工管理系统,实现施工过程的信息化管理。本项目的BIM技术应用涵盖了勘测、设计、施工阶段,形成了前期应用、协同设计和施工管理的一套全过程应用流程和方法
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:本研究从铁路路基健康监测出发,基于FDM(Fused Deposition Modeling)与FBG(Fiber Bragg Grating)技术开发了路基小变形监测系统。利用FDM技术和FBG传感技术设计带封装和锚固板的FBG传感器监测模型,标定试验可得荷载与土体位移的关系,结果表明:位移与荷载呈良好的线性关系,相关系数达到0.99,标试验测得最大位移为0.25 mm,最小位移为0.05 mm,传感器灵敏度达到4 nm/mm,最小分辨率达到0.62 µm。通过两种试验工况检验传感器可行性,包括监测路基在静、动载作用下的位移变化,静荷载作用下监测数据表明:波长及位移随时间呈阶梯性增长,试验成功采集路基的最小位移达到0.004 mm。动荷载监测试验结果表明传感器可以快速反映车辆模型荷载产生的竖向压力。
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:广西乐百弄衣隧道属于特长隧道,在隧道施工过程中,由于地质构造异常复杂,对于质量、安全的控制非常严格。隧道开挖的地质预报资料尤为重要,需排除前方不良地质、水纹条件,同时,隧道开挖过程中的超挖、欠挖工程量统计成为了传统施工的一个难点。此外,隧道的不均匀沉降监测数据实时记录更新及现场进度、质量、安全等均急需新型项目管理工具来辅助提升协同管理效率。针对以上隧道的施工重点难点,团队经过多次不同BIM系列软件的比对分析,采取了Revit+Dynamo+Civil3D+BIM5D的BIM解决方案,可解决从BIM模型搭建到项目各阶段的管理应用难题,如:清单工程量统计分析、以日为基准单位的施工进度管理、按每延米桩号定位辅助解决施工质量安全问题等等。利用本隧道BIM解决方案可根据现场施工实际信息数据进行深化模型,并多方位多角度辅助解决各类传统隧道施工的难点。本项目课题研究的成果可供类似公路工程BIM应用提供专业的技术解决参考方案。
Subjects: Civil Engineering and Building Construction >> Basic Disciplines of Civil Engineering and Building Construction submitted time 2018-10-26 Cooperative journals: 《土木建筑工程信息技术》
Abstract:目前的BIM应用与各种新兴信息技术相结合,在多领域均有其身影,而铁路四电工程因其多专业交叉、施工难、跨自然区域大等特点,迫切地需要BIM来提高设计、施工的效率。为使BIM在铁路四电工程中更好地应用