Application of 4D for dynamic site layout and management of construction projects

Construction schedules and site space arrangement are essential to project management, as they directly influence security, machine running, material deployment, power distribution as well as construction progress and cost. There has been a strong need for more effective planning and management of site space and facilities. This paper introduces a 4D Integrated Site Planning System (4D-ISPS) which integrates schedules, 3D models, resources and site spaces together with 4D CAD technology to provide 4D graphical visualization capability for construction site planning. The features of 4D-ISPS are described in detail. The implementation techniques of this system are also discussed and a real life case is presented.     

4D CAD model updating using image processing-based construction progress monitoring

For a four-dimensional (4D) computer-aided design (CAD) model to be useful for users throughout a construction project, the model must be updated in a timely and accurate manner during the construction. Only when it has been properly updated can the 4D CAD model reflect the real progress of a construction site to inform managerial decision making. However, updating a 4D CAD model is time-consuming and labor-intensive because the full updating process, from site data acquisition to 4D model regeneration, is typically conducted manually. This difficulty in updating a 4D model discourages industry practitioners from actively adopting 4D models. This paper presents an image processing-based methodology for the automatic updating of a 4D CAD model. Characterized by 3D CAD-based image mask filters, color-based noise removal, and area-based progress calculation, the image processing approach provides as-built schedule information. The schedule information is then automatically integrated with an existing 3D CAD model in batch-processing modes to produce the updated 4D CAD model. The proposed methodology was applied and verified in a cable-stayed bridge construction project and is expected to facilitate the wider use of 4D CAD models in the construction industry.     

建设项目施工过程的造价控制对策探讨

针对目前项目施工过程中存在的各类造价失控现象,结合工程施工实际,较系统的提出了优化施工方案、统筹现场管理、规范工程签证、加强合同管理、减少工程分包、把好甲供材料关等造价控制的措施和对策。     

路桥工程项目成本控制

项目成本控制是企业生存和发展的基础和核心,在施工阶段搞好成本控制,达到增收节支的目的是项目经营活动中最为重要的环节。项目成本控制,指在项目从投标到交付成果过程中,对生产经营所消耗的人力资源、物质资源及相关费用,进行指导、监督、调节和限制,及时纠正将要发生和已经发生的偏差,把各项生产费用控制在计划成本的范围之内,以保证成本目标的实现。     

国际建筑总承包工程国内物资采购管理

在国际建筑总承包工程项目中,物资采购管理工作是总承包工程管理的一个重要组成部分,物资采购的质量、进度、费用直接影响总承包工程的质量、工期和造价。只有把国内物资采购的管理工作做好,才能确保国外工程的顺利完成。     

室外标准田径运动场项目工程管理

室外田径运动场属于较特殊的一类建设项目,在项目实施过程中,极易出现管理困难的局面,也容易产生工程质量问题。通过一室外标准田径运动场在建设施工过程中暴露出来的关键问题,从审核施工图设计、严把原材料关和加强施工现场关键环节控制三个方面对项目实施了有效的工程管理与质量、造价控制,达到了设计标准,确保了建设质量。     

建筑钢结构设计阶段的工程造价控制

指出了设计阶段是控制工程造价、提高建筑经济性能的关键,以门式刚架轻钢结构厂房和多、高层钢结构建筑设计为例,在材料选用、结构体系等方面进行了简要分析,并探讨了控制工程造价的可行性.     

An evaluation of the applicability of 4D CAD on construction projects

4D CAD models that integrate physical 3D elements with time, have been used to visualize construction processes in several projects worldwide. 4D models have been used and have been shown to have benefits over processes that span the entire lifecycle of a project such as collaboration with stakeholders, making design decisions, assessing project constructability, identifying spatial conflicts in construction and so on. Despite these benefits, several organizational and project-specific barriers have hindered the widespread adoption of 4D CAD. In order to reconcile the theoretical benefits of 4D models with the practical difficulties faced in implementation, there is an urgent need to explore the implementation of 4D models on construction sites as well as the perceptions of intended users/beneficiaries towards this implementation. This paper aims to address this need and contribute to our understanding of how 4D models must be introduced, positioned and implemented on construction sites, so as to maximize both their acceptability and their usefulness. We describe two 4D models of infrastructure projects and two 4D models of commercial projects that have been built and implemented. Through a process of structured and unstructured interviewing the paper gauges the response of project participants across various organizational levels on each of these projects as to the usefulness of 4D in project planning and control. Through qualitative and statistical analysis of the data we establish that 4D CAD is likely to be most beneficial in the project shaping or planning stage and in the construction stage. In the project shaping stage, 4D CAD is likely to be particularly useful in communicating construction plans and processes to clients, while during the construction phase, 4D CAD is likely to be particularly useful in comparing the constructability of work methods visually in order to detect conflicts or clashes, and as a visual tool for contractors, clients, subcontractors and vendors to review and plan project progress. Further, upper management and site workers are more likely to use and derive benefits from the visualization of processes using 4D given their lack of site related knowledge or skills, while construction professionals who are more construction-savvy are more likely to appreciate and benefit from the analytical and planning aids that 4D simulations provide during the construction phase. However, it is likely that despite these benefits 4D CAD models might not diffuse through the construction industry unless 4D modelling and analysis is integrated into existing project planning approaches. The paper concludes with a brief discussion on future 4D software development that seeks to bring about such integration and leverages the benefits of 4D CAD to bring about improved operational efficiencies on construction sites.     

Optimisation of site layout planning for multiple construction stages with safety considerations and requirements

This paper develops a mathematical formulation to model and optimise site facility locations inside a construction site for a construction project's different stages. The existence and dimensions of a construction project's available locations and site facilities can be varied across the construction stages. Without proper planning, unnecessary facility relocations may be required in each construction stage, resulting in a higher construction cost and longer construction time due to the need to dismantle and set up site facilities. Site layout plans should be optimised using a multiple-stage model to avoid unnecessary changes to facility settings across construction stages, improving efficiency. The proposed site layout problem with multiple construction stages is formulated as a binary-mixed-integer-linear programme, which can be solved by a standard branch-and-bound algorithm using the commercial software package LINGO. The mathematical objective function established in the solution process aims to minimise the total cost, which consists of the material transportation cost between the relevant site facilities and the dismantling, setup and relocation costs for all of the involved site facilities in each construction stage. Numerical examples using the proposed mathematical model to optimise different site layout settings for a construction site are given, including (1) a reference site layout plan using the conventional static single-stage approach, (2) a multiple-stage construction site layout plan and (3) a multiple-stage site layout plan with additional safety design considerations.     

建设全生命周期内的低碳电厂

在现代工业建设中,原始的高能耗、高污染设计方法违背低碳原则,对建设成本应该从工业建筑的整个生命周期的角度来考虑。针对某实际电厂设计项目,讨论了一整套有效的低碳电厂建设方法。介绍了一套符合我国国情的低碳设计准则;讨论了低碳电厂的一些设计方法;提出了一种基于废弃稻谷灰的混凝土着色技术,用于改善电厂的外观和降低建设成本;最后...     

浅析创精品工程的建筑施工管理--以赣榆县行政服务中心（主楼）为案例讲述

施工管理是建筑项目最关键的环节,所涉及的内容覆盖整个工程建设。项目经理想实现创优工程,首先就是要做好施工现场的管理工作,以保证施工顺利进行。本文就以赣榆县行政服务中心（主楼）工程项目为例讲述建筑工程施工管理具体内容,主要是从安全、进度、质量与成本四个方面进行分析,以供广大同行参考。     

Automated multi-objective construction logistics optimization system

Construction logistics planning entails the coordination of supply and site activities by integrating their decisions and recognizing existing interdependencies to minimize the total material management cost. Despite the preliminary estimates of its benefits to the construction industry, few contractors adopted logistics management because of its demand for detailed data and decision of material supply and site operations. This paper presents the development of a new automated multi-objective construction logistics optimization system (AMCLOS) that would support the contractors in optimally planning material supply and storage. AMCLOS provides a holistic framework of automatically retrieving project spatial and temporal data from existing scheduling and BIM electronic files, seamlessly integrating relevant contractor and suppliers' data, and optimizing material supply and site decisions to minimize total logistics costs. The performance of AMCLOS was validated against a previous construction logistics planning model, which provided useful insights on material supply and storage logistics in congested and spacious sites. The developed system is envisioned to increase the implementation of logistics management practices and early integration and coordination of construction supply and site processes.     

结构设计阶段优化工程造价成本的思路及对策

工程造价成本的控制不仅是对建筑方案阶段和建筑设计阶段的造价进行控制,还应当对结构设计阶段等进行优化。通过分析结构设计方案、结构设计过程和结构设计质量对工程造价成本影响,提出基于全生命周期的工程造价成本控制和形成系统化工程造价管控模式的两点优化思路,并提出应用价值工程设计优化、建立结构方案内部评审机制等具体优化对策。以期为实现工程目标价值与实际价值的最小偏离提供帮助。     

BIM在施工成本管理中的应用

BIM模型作为新型建造管理技术,其改变了传统的建造管理模式,是一种动态的管理模式。在施工阶段全过程引入BIM技术,可以精准地预测项目成本,合理安排人、材、机和资金等相关资源计划,优化设计变更过程。结合相关实例,探讨BIM技术在施工前期的深化设计与施工模拟、施工过程中工程计量与进度管理、后期竣工结算管理等方面的具体应用,为施工企业进行施工成本精细化管理提供借鉴。     

工程咨询公司全过程造价控制及效果评价研究

通过分析工程咨询公司在全过程造价管理模式下存在的问题,构建工程咨询公司全过程造价控制模式,包括决策阶段项目建议书和可行性研究报告中的投资估算、设计阶段的方案设计和初步设计概算以及实施阶段的工程招投标中的标底和合同价、施工过程中的动态造价及竣工结算中的造价审核监督和控制等。通过建立咨询服务效果评价指标体系,确定评价指标权向量,建立综合评价模型,探讨工程咨询公司全过程造价控制效果评价方法。并指出全过程造价控制效果评价应注意的事项。分析结果表明,工程咨询公司应在项目建设周期的全过程中采取有效措施,进行工程造价有效控制及控制效果评价,节约成本,合理利用资源。     

论天然气净化厂工程造价控制的重点环节

造价管理是为了真实、正确、合理地反映工程造价,控制工程投资,节省建设资金,建设项目涉及面广,内容繁多,只有抓住造价管理的重点,才能更好地发挥工程造价管理的功能.天然气净化厂工程建设造价控制的重点:一是高度重视设计环节;二是实行概算转批,并对概算进行分解控制;三是高度重视设备物资采购环节;四是向工程量清单计价过渡;五是加强施工现场管理;六是加强与当地政府的协调勾通.所以,分清主次,突出重点是控制工程造价的有效途径.     

老旧小区改造项目成本管理难点和措施研究

受多重因素影响,老旧小区改造项目建设难度逐渐加大,工程施工成本不断上涨.结合具体实例,分析当前老旧小区改造过程中面临的项目成本管理难点,有针对性地提出应对措施,包括科学制定施工组织设计、提高施工人员综合素质、强化施工现场管理、加强与居民沟通、加强材料成本管控、加强工程变更成本控制管理等,为老旧小区改造项目实施过程中提升...     

A hybrid CAD-based construction site layout planning system using genetic algorithms

The efficient layout planning of a construction site is a fundamental task to any project undertaking. In an attempt to enhance the general practice of layout planning of construction sites, the paper introduces a novel approach for producing the sought layouts. This approach integrates the highly sophisticated graphical capabilities of computer-aided design (CAD) platforms with the robust search and optimization capabilities of genetic algorithms (GAs). In this context, GAs are utilized from within the CAD environment to optimize the location of temporary facilities on site. The functional interaction between GAs and CAD and the details of the GA-based layout optimization procedure are presented. A fully automated computer system is further developed to demonstrate the practicality of the chosen approach. In order to evaluate the system's performance, a local construction project with a 24,000m² site is used. The automated system produced highly satisfactory results and showed notable flexibility through its CAD-based input/output media.     

Integrating resource production and construction using BIM

This paper presents the outcomes of a research and development project carried out at the University of Maribor, Construction IT Centre, with regard to the introduction of a building information model (BIM) and a model based construction process into the operational environment of a construction company. The initiative for the project came from the industry and was performed as a joined effort of the research organization and the construction company. Work was performed in the scope of an industrialized construction environment, with the main aim to integrate mass production prefabrication processes with construction site activities. BIM was used as a link between an enterprise resource planning (ERP) information system that supports manufacturing process and construction object related information, mainly handled by CAD tools. The benefits of this link are presented with regard to project progress monitoring and material flow management.     

工厂全生命周期土建三维设计流程探索

分析了工厂三维设计中土建结构三维设计流程在EPC项目运作模式中的应用优势和实行的可行性和必要性。在客户对工厂数字化管理需求日益增加的形势下,土建结构设计也必须更有机地融入到工厂三维设计的一体化流程之中。在研究了土建三维设计相关软件及其转换可行性基础上,提出应用基于结构分析设计软件、接口软件、土建制造、施工安装管理软件以及工厂三维设计软件相互集成的土建三维设计的两种可行的流程,实现在总承包项目全生命周期中项目参与各方的利益最大化和结构建模信息数字资源利用。