Dynamic quantification and analysis of the construction workspace congestion utilising 4D visualisation

This work focuses on identifying and minimising workspace congestions between construction activities' execution space. It develops a methodology and tool to assist planners with the assignment of activities' execution space, as well as identification and visualisation of workspace congestion. A literature review of workspace planning techniques revealed that traditional workspace planning techniques might not be able to detect and resolve workspace congestions.This paper establishes a new concept for ‘visualising workspace competition’ between the progressing activities through a number of objectives. A Critical Space-time Analysis (CSA) approach was developed to model and quantify workspace congestions. Subsequently a multi-criteria function embedding spatial and schedule related criteria, was designed to measure the severity of workspace congestions. A dynamic 4D simulation environment was developed by utilising three workspace planning features, these are: the twelve execution patterns, the three different work rate distributions, and a time-based simulation of the progressing quantities of work. These were encapsulated in an innovative visual 4D CAD tool dubbed PECASO (Patterns Execution and Critical Analysis of Site-space Organisation), which was developed and evaluated in a case study project.The paper concludes that the CSA approach reduces the number of competing workspaces and conflicting volumes between occupied workspace. The PECASO tool assists the planners' decision making to produce a better execution strategy for a given project schedule. It also contributes to future research and knowledge of 4D workspace planning.     

Virtual experiment of innovative construction operations

The planning of construction operations is a complicated activity involving abstraction of construction activities from the drawings, choosing of suitable plants and falseworks, allocation of resources on site, planning of safe working place for labourers, and the scheduling of activities sequence. The increasing competition among contractors demands them to adopt innovative construction methods, which have not been used or tested previously. It is not until the beginning of actual construction that the construction planner can realize the validity of his construction operations planning. The lack of tools for the construction planner to evaluate and validate his planning can result in incorrect construction plans, which cause a lot of rework in the construction phase. Virtual Reality (VR) technology, on the other hand, is very likely to provide a solution to the above problem. VR system generates virtual environment containing objects with real world properties and allows user/planner to interact with the objects. This paper proposes an integrated VR system that generates near to reality construction environment for the construction planner to perform construction activities in a real world manner in order to plan, evaluate and validate the construction operations.     

Task planner design for an automated excavation system

An automated excavation system, which is a robotic excavator with site modeling capability, is being developed by a Korean research consortium in order to improve the productivity, quality, and safety of conventional earthwork. This paper presents the excavation task planner devised to incorporate the intelligence of a construction planner and a skillful operator into the robotic control mechanism of the automated excavation system. The excavation task planner aims to generate an optimal excavation plan based on 3D models of the work environment and the excavator updated by various cognitive technologies. The structure of the task planner was designed in harmony with the sensing and the control schemes of the automated excavation system. The algorithms used to partition the work area and to generate the excavator path were developed as the critical components of the task planner. The suggested design of the excavation task planner focused on the functions required to utilize the automated excavator at actual construction sites. Case studies showed that the task planner was able to generate effective work plans that could be fed into the automated excavation system.     

Generating, evaluating and visualizing construction schedules with CAD tools

Collaborative AEC technologies centering around component-based CAD models support architectural and structural perspectives. The construction perspective is often neglected because an important dimension for construction–time–is missing. Construction planners are forced to abstract CAD model building components into schedule models representing time. 4D-CAD (3D-CAD+time) removes this abstraction by linking a 3D building model and schedule model through associative relationships. Adding time to 3D-CAD models extends the use of CAD tools from the design phase to the construction phase. Although commercial 4D tools exist that allow planners to build 4D models and create graphic simulations of the construction process, these tools lack features to support analysis of these models, easy generation and manipulation of such models, and realistic visualizations of the construction process. This paper discusses these shortcomings, highlights requirements for CAD tools to support construction planning tasks, and describes our efforts to develop 4D tools that generate 4D+x models that more realistically represent the construction process.     

关于电气专业施工图纸审读工作的探讨

施工准备阶段进行审图,可保证和提高工程质量、控制及节约工程成本、合理安排进度以保证工期要求。归纳了完整有效性、供配电系统、防雷、接地系统及安全措施、设备及器具安装、与其他专业的配合等几个方面的内容对电气专业图纸审读工作的主要内容。     

BIM- and 4D-based integrated solution of analysis and management for conflicts and structural safety problems during construction: 1. Principles and methodologies

Strengthening construction safety analysis and management is of great social and economic significance. For a long time, however, there has been a lack of effective management tools in this important area that involves people's lives and property. Based on new developments in the Building Information Model (BIM), four-dimensional (4D) technology, time-dependent structural analysis, collision detection, and so on, a 4D structural information model is presented and established according to the overall solution of analysis and management for conflict and safety problems during construction. Based on this sub-BIM, the integration of dynamic safety analysis of time-dependent structures, conflict analysis and management of schedule/resource/cost, and dynamic collision detection of site facilities is studied, and theories and key technologies are discussed in detail. The results of this research provide a feasible theory and methodology for integrated applications of BIM. Furthermore, this study proposes a new approach for conflict and safety analysis during construction through the integration of construction simulation, 4D construction management, and safety analysis. The approach lays a foundation for the popularization of complicated theories and methodologies, and has theoretical significance and application prospects in meeting the needs of improving the safety level during construction.     

An integration of the fuzzy reasoning technique and the fuzzy optimization method in construction project management decision-making

Most real world decision-making combines quantitative and qualitative (linguistic) variables. Conventional mathematics that combines qualitative and quantitative concepts exhibits difficulty in modelling actual problems. The research presented in this paper illustrates a mathematical approach to the solution of decision-making problems that combine qualitative and quantitative objectives. A methodical system for construction project management decision-making was developed using a combination of fuzzy multiple-objective decision-making theory and the fuzzy reasoning technique. The mathematical model can be applied to construction project management problems by suggesting an optimal path of corporate cash flow that results in the minimum use of resources. The information provided by the mathematical model allows the planner to eliminate excess use, or idleness, of resources during the construction of a project. Such information is indispensable for decision-makers in analysing the best time to invest in a new project. A case study is demonstrated to illustrate the application to a management decision problem.     

基于SuperMap IS的西安市空间数据发布系统建设

结合西安市空间数据发布系统建设的具体实际,介绍了利用北京超图地理信息有限公司GIS平台Super Map开发空间数据发布系统的情况,重点介绍了该系统的结构设计及海量空间数据库的数据组织方法。     

Construction Workspace Planning: Assignment and Analysis Utilizing 4D Visualization Technologies

Abstract:   This article describes a construction activity execution space analysis approach and a decision support tool for resolving execution space interference and conflict between work-face construction activities. Lack of execution pace planning interrupt and badly affect the progress of construction activities. Also, in real situations, spatial congestion can severely reduce the productivity of workers sharing the same workspace, and may cause health and safety hazard issues. The aim of this article is to present a critical space-time analysis (CSA) approach that was developed to model and quantify workspace congestion and was encapsulated in a computerized tool dubbed PECASO (patterns execution and critical analysis of site-space organization) that was developed to assist site managers in the assignment and identification of workspace conflicts. A new concept of "visualizing workspace competition" between the construction activities is presented based on a unique representation of the dynamic nature of activities within the execution workspace, in 3D space and time. PECASO embraces 4D visualization and highlights the critical space control aspect to formulate an innovative 4D space planning and visualization tool. The CSA methodology and PECASO were validated using a real case study and the article concludes that the PECASO system has the potential to reduce the number of competing workspaces, as well as the conflicting volume/space between occupied workspaces. This in turn produces better assessment of the execution strategy for a given project schedule. Additionally, the PECASO system has introduced a new way of communicating the program of work in a high level of detail for space planning purposes.     

Automated construction sequencing and scheduling from functional requirements

Functional requirements are among the critical factors which govern the sequencing logics of a construction schedule. They refer to the requisites of functional dependencies among components in both construction and completion phases. Automated reasoning from functional requirements into sequencing logics is currently a challenge in construction planning. This paper introduces a model called FReMAS – a Functional Requirement Model for Automatic Sequencing – which is an attempt to automate sequencing and scheduling from functional requirements. It provides a generic representation schema and a systematic reasoning framework to capture, reason and convert functional requirements into temporal constraints between schedule elements. FReMAS is implemented in ECLⁱPS^e, and an illustrative example of a nursing building construction is employed to demonstrate its application. FReMAS automatically determines possible sequences and generates all schedule alternatives that satisfy all imposed construction requirements while minimizing the project makespan. With the capability of automatic sequencing and alternative scheduling, FReMAS can help improve the effectiveness and adequacy of the planning process.     

A framework for rapid local area modeling for construction automation

Rapid 3D positioning and modeling in construction can be used to more effectively plan, visualize, and communicate operations before execution. It can also help to optimize equipment operations, significantly improve safety, and enhance a remote operator's spatial perception of the workspace. A new framework for rapid local area sensing and 3D modeling for better planning and control of construction equipment operation is described and demonstrated. By combining human-assisted graphical workspace modeling with pre-stored Computer-Aided Design (CAD) models and simple sensors (such as single-axis laser rangefinders and remote video cameras), modeling time can be significantly reduced while potentially increasing modeling accuracy.     

Extending BIM interoperability to preconstruction operations using geospatial analyses and semantic web services

Since the early 2000s, building information modeling (BIM) has been used through the entire project life cycle to facilitate effective project collaboration and integration of data to support project activities. Despite the successful applications of BIM in the design and construction stages, the use of BIM for preconstruction planning has not gained wide acceptance as in other project phases. The integration of BIM and geospatial analyses can offer substantial benefits to manage the planning process during the design and preconstruction stages. However, this integration suffers from a lack of interoperability across the geospatial and BIM domains. Semantic web technology is used in this study to convey meaning, which is interpretable by both construction project participants as well as BIM and geographic information systems (GIS) applications processing the transferred data. To achieve this, we first translate building's elements and GIS data into a semantic web data format. Then we use a set of standardized ontologies for construction operations to integrate and query the heterogeneous spatial and temporal data. Finally, we use a query language to access and acquire the data in semantic web format. Through two scenario examples, the potential usefulness of the proposed methodology is validated.     

Optimizing schedule for improving the traffic impact of work zone on roads

Many different types of construction projects set up work zones on roads. Especially in urban areas, lane closures as a result of work zones have a considerable impact on local traffic. However, for a construction project that consists of several work zones and several work crews, the traffic impact may be improved by appropriate scheduling. Therefore, this paper proposed a scheduling model based on the route-changing behavior of road users. The proposed model calculates the traffic delay of vehicles by microscopic simulation, and applies team ant colony optimization to search for a near-optimal schedule. The project planner then ensures that the contractor executes the activities according to the near-optimal schedule. The proposed model is applied to schedule a sewer system construction project in a city. The results of our study indicate that with our proposed model the total traffic delay is reduced by 11.1% when compared with a schedule proposed by the project planner.     

数字乌鲁木齐地理空间框架建设的分析及思考

通过"数字乌鲁木齐地理空间框架建设"项目的实施,从技术方案、目标、内容和关键技术的阐述,围绕"一库一平台N应用"建设模式,对"数字乌鲁木齐"建设进行了分析,通过对设计、建设、应用、评价以及存在的问题等几个方面的论述,全面评价框架建设成果的实效性。     

如何进行工程造价竣工结算审核

对合同,协议,招投标文件,工程量清单,中标价,设计图纸以及会审纪要等的审核是造价审核的基础和前提工程量的审核是造价审核的根本子目套用是造价审核的重点材料价格的审核是造价审核的重中之重签证的审核是造价审核成功的保障工程类别及费用的审核是造价审核的最后关口防止各种计算误差是造价审核的关键.     

BIM技术在长江传媒大厦项目中阶段性应用(一)

本文介绍了BIM技术在武汉长江传媒大厦项目中现阶段的应用,该项目为超高层大型公建项目,其内部管线密集且对空间净空要求高,以及在大跨度钢结构拼装吊装等施工工艺以及工序方案上问题较多,通过BIM技术在利用信息模型对项目进行碰撞检查并导出管线综合排布优化图纸,对施工现场项目安全方案演示,以及对大跨度钢梁吊装等方案进行可视化演示模拟,进一步加强了BIM技术对于现场施工的指导,确保了对施工安全和质量的管理控制。     

浅谈BIM在施工企业中的应用

根据我国现阶段的建设环境,针对施工企业特点,发掘BIM模型、4D模拟施工、4D管理软件等对施工企业现场施工作业的指导意义,通过对施工项目的工程量计算、碰撞检查、工法改进、人员安排、施工机械配置、材料的准备和预制、现场BIM安全分析、施工过程中关键工作的进度控制等方面的分析,挖掘出BIM对施工企业的更多价值。     

The time dimension in site layout planning

With regard to incorporation of the time factor, site layout models are traditionally grouped into two categories of static models (with no considerations of the changes over time), and dynamic models (reflecting the changes on the construction sites). This paper demonstrates that there are in fact fundamental differences in the assumptions and the final outcome of models that are currently all categorized under dynamic site layout planning models, and proposes that these should in fact be divided into two groups of phased and dynamic models. The paper provides a comparative analysis of the three approaches of static, phased and dynamic site layout planning. The strengths, limitations, and differences in the final results of the three approaches are demonstrated through numerical examples. Finally, existing methods for the 2D representation of dynamic site layouts are compared, and an improved algorithm is provided to represent dynamic site layouts in minimum number of overlap-free drawings.     

某多层钢结构厂房施工方案

钢结构工业厂房中多层厂房占有的比例呈逐年增高之势,选择施工方案的优劣对工程质量、经济性、工期、安全性能都有很大的影响,每个工程都要根据工程本身的特点选择适合该工程的最佳施工方案,当然不同的工程环境、所处不同的地区,不同的施工季节对工程方案都有很大的影响。本文针对该多层钢结构厂房的特点难点分析、安全防护、施工方案等梳理介绍。     

Development of a schedule-workspace interference management system simultaneously considering the overlap level of parallel schedules and workspaces

Schedule-workspace interference is generated when workspaces that share parallel schedules and are physically adjacent to one another exist simultaneously. When workspace interference is generated, securing work performance safety is difficult and constructability can deteriorate due to increased collision risk between resources. The objective of this study is to realize an active simulation system based on building information modeling (BIM) after constructing a genetic algorithm (GA) process for an alternative schedule that minimizes the simultaneous interference level of the schedule-workspace. To accomplish this task, the impact factor of workspace interference, which simultaneously considers schedule overlap and adjacency, was analyzed. From the impact factor, an optimized algorithm based on a location-constraint GA that can minimize workspace interference is suggested. The GA visually simulates the optimization level of the execution schedule compared to the initial plan through interlock with four-dimensional (4D) computer-aided design (CAD). A 4D CAD system that can analyze workspace interference by a GA was developed, and for the developed algorithm and system, a case verification was attempted for a railroad construction project. The results show how a simple visualization-oriented BIM system can be extended to an active schedule management system equipped with decision-making functions of workspace analysis.