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Cost and Schedule Controlling in Relation to Liquidity Management during Construction Projects
(2004)
The present paper describes a software application which can be used for relating the scheduled events of a construction project with the respective financial parameters, leading to an overall improvement in general controlling and liquidity management. For this purpose, existing construction schedules are taken and details of the assignment are recorded. Thus it becomes possible to assess a future payment status should changes in the designated schedule occur.
The methods currently used for scheduling building processes have some major advantages as well as disadvantages. The main advantages are the arrangement of the tasks of a project in a clear, easily readable form and the calculation of valuable information like critical paths. The main disadvantage on the other hand is the inflexibility of the model caused by the modeling paradigms. Small changes of the modeled information strongly influence the whole model and lead to the need to change many more details in the plan. In this article an approach is introduced allowing the creation of more flexible schedules. It aims towards a more robust model that lowers the need to change more than a few information while being able to calculate the important propositions of the known models and leading to further valuable conclusions.
Some key facts about the economic environment of construction industry are explained. It is shown that construction industry is very heterogeneous and has changed drastically during the recent years due to a rapidly moving commercial environment. Two examples of todays’s use of virtual construction tools in construction projects are presented. The first example is the document control for a large international project. The second is the application of 4D modelling in the preconstruction phase of a dam project. It is shown that virtual construction, is a major international trend that currently takes up speed. Some generic industry needs for Research and Development which aims at short and medium term results are presented.
As computer programs become ever more complex, software development has shifted from focusing on programming towards focusing on integration. This paper describes a simulation access language (SimAL) that can be used to access and compose software applications over the Internet. Specifically, the framework is developed for the integration of tools for project management applications. The infrastructure allows users to specify and to use existing heterogeneous tools (e.g., Microsoft Project, Microsoft Excel, Primavera Project Planner, and AutoCAD) for simulation of project scenarios. This paper describes the components of the SimAL language and the implementation efforts required in the development of the SimAL framework. An illustration example bringing on-line weather forecasting service for project scheduling and management applications is provided to demonstrate the use of the simulation language and the infrastructure framework.
Indentation experiments have been carried out over the past century to determine hardness of materials. Modern indentation machines have the capability to continuously monitor load and displacement to high precision and accuracy. In recent years, research interests have focussed on methods to extract material properties from indentation load-displacement curves. Analytical methods to interpret the indentation load-displacement curves are difficult to formulate due to material and geometric nonlinearities as well as complex contact interactions. In the present study, an artificial neural network model was constructed for interpretation of indentation load-displacement curves. Large strain-large deformation finite element analyses were first carried out to simulate indentation experiments. The data from finite element analyses were then used to train the artificial neural network model. The artificial neural network model was able to accurately determine the material properties when presented with load-displacement curves which were not used in the training process. The proposed artificial neural network model is robust and directly relates the characteristics of the indentation loaddisplacement curve to the elasto-plastic material properties.
The truss model for predicting shear resistance of reinforced concrete beams has usually been criticized because of its underestimation of the concrete shear strength especially for beams with low shear reinforcement. Two challengers are commonly encountered in any truss model and are responsible for its inaccurate shear strength prediction. First: the cracking angle is usually assumed empirically and second the shear contribution of the arching action is usually neglected. This research introduces a nouvelle approach, by using Artificial Neural Network (ANN) for accurately evaluating the shear cracking angle of reinforced and prestressed concrete beams. The model inputs include the beam geometry, concrete strength, the shear reinforcement ratio and the prestressing stress if any. ...
This paper is a report of Radio Frequency Identification (RFID) technology and its potential applications in the commercial construction industry. RFID technology offers wireless communication between RFID tags and readers with non line-of-sight readability. These fundamental properties eliminate manual data entry and introduce the potential for automated processes to increase project productivity, construction safety, and project cost efficiency. Construction contractors, owners, and material suppliers that believe technology can further develop methods and processes in construction should feel obligated to participate in RFID studies for the advancement of the construction industry as a whole.
At the start of the conceptual design process, designers start to give tangible form to their thoughts by sketching. This helps with reasoning and communicates ideas to other members of the team. Sketches are gradually worked up into more formal drawings which are then passed to the other stages of the design process. There are however some problems with basing early ideas on sketching. For example, due to their ad-hoc nature, sketches tend only to be diagrammatic representations and so designers cannot be sure that their ideas are feasible and what is being proposed meets the constraints described in the client brief. This can result in designers wasting time working up ideas which prove to be unsuitable. Also the process of constraint checking is complex and time consuming and so designers tend limit their search of possible options and instead choose satisfying rather than good solutions. This paper describes the INTEGRA project which examines the role of sketching in early conceptual design and how this can be linked to other aspects of the process and particularly automated constraint checking using an IT based approach. The focus for the work is the design of framed buildings. A multi-disciplinary approach has been adopted and the work has been undertaken in close collaboration with practising designers and clients.
Als Folge des hohen Termindrucks während des Bauablaufes, ist es besonders wichtig den Fortschritt eines Bauvorhabens zeitnah zu überwachen. Auf Großbaustellen kann die effektive Kontrolle nicht mehr ohne technische Hilfsmittel durchgeführt werden. Die Arbeit stellt verschiedene Szenarien für die verteilte Fortschrittserfassung vor und untersucht welche Anforderungen an ein System für die verteilte Erfassung gestellt werden. Dazu wird zuerst das bestehende CVS-System analysiert, um anschließend daraus ein Konzept für die Versionierung von Objekten und den automatischen Abgleich von Objektversionen zu entwickeln. Später wird gezeigt, wie dieses Konzept mit Hilfe von C# und dem Microsoft®-.NET-Framework umgesetzt werden kann.
Building project, with many different players involved, requires open and commonly accepted standard for product model description. Product model based design tools support easy comparisons of design alternatives and optimisation of design solution technical quality. This supports client s decision-making and design target comparisons through the whole building project. Use of product models enable these tasks to meet both schedule and cost requirements Olof Granlund is using product models and interoperable software as the main tool in projects. The use and the realised benefits are illustrated by examples from 3 different real projects: University building, where product models were used already in the very early phases by the whole design team. Office building for research organisation, where product models were used in so called self-reporting building system. Headquarters for international company, where product models were widely used for building performance analysis and visualisations in design phase as well as for facilities management system configuration for operational phase.
This paper focuses on a new three-level discretisation strategy which enables the transition between continuum/structural (I) and structural/black box modelling (II). The transition (I) is realised by means of a model adaptive concept based on an innovative finite element technology. For transition (II) we apply the truncated balanced realisation method (TBR). The latter represents an established system theoretical model reduction technique which is here combined with a novel substructure technique. The approach provides a modular concept to facilitate the computational analysis of complex structures. The final goal is to apply the strategy to life time estimation.
The promise of lower costs for sensors that can be used for construction inspection means that inspectors will continue to have new choices to consider in creating inspection plans. However, these emerging inspection methods can require different activities, resources, and decisions such that it can be difficult to compare the emerging methods with other methods that satisfy the same inspection needs. Furthermore, the context in which inspection is performed can significantly influence how well certain inspection methods are suited for a given set of goals for inspection. Context information, such as weather, security, and the regulatory environment, can be used to understand what information about a component should be collected and how an inspection should be performed. The research described in this paper is aimed at developing an approach for comparing and selecting inspection plans. This approach consists of (1) refinement of given goals for inspection, if necessary, in order to address any additional information needs due to a given context and in order to reach a level of detail that can be addressed by an inspection activity; (2) development of constraints to describe how an inspection should be achieved; (3) matching of goals to available inspection methods, and generation of activities and resource plans in order to address the goals; and (4) selection of an inspection plan from among the possible plans that have been identified. The authors illustrate this approach with observations made at a local construction site.
The approach discussed here is part of research into an overall concept for digital instruments which support the entire planning process and help in enabling planning decisions to be based upon clear reasoning and plausible arguments. Such specialist systems must take into account currently available technology, such as networked working patterns, object-orientation, building and product models as well as the working method of the planner. The paper describes a plausibility instrument for the formulation of colour scheme proposals for building interiors and elevations. With the help of intuitively usable light simulations, colour, material and spatial concepts can be assessed realistically. The software prototype “Coloured Architecture” is conceived as a professional extension to conventional design tools for the modelling of buildings. As such it can be used by the architect in the earliest design phases of the planning process as well as for colour implementation on location.
Structural engineering projects are increasingly organized in networked cooperations due to a permanently enlarged competition pressure and a high degree of complexity while performing the concurrent design activities. Software that intends to support such collaborative structural design processes implicates enormous requirements. In the course of our common research work, we analyzed the pros and cons of the application of both the peer-to-peer (University of Bonn) and multiagent architecture style (University of Bochum) within the field of collaborative structural design. In this paper, we join the benefits of both architecture styles in an integrated conceptual approach. We demonstrate the surplus value of the integrated multiagent–peer-to-peer approach by means of an example scenario in which several structural engineers are co-operatively designing the basic structural elements of an arched bridge, applying heterogeneous CAD systems.
Although there are some good reasons to design engineering software as a stand-alone application for a single computer, there are also numerous possibilities for creating distributed engineering applications, in particular using the Internet. This paper presents some typical scenarios how engineering applications can benefit from including network capabilities. Also, some examples of Internet-based engineering applications are discussed to show how the concepts presented can be implemented.
Assuring global consistency in a cooperative working environment is the main focus of many nowaday research projects in the field of civil engineering and others. In this paper, a new approach based on octrees will be discussed. It will be shown that by the usage of octrees not only the management and control of processes in a network-based working environment can be optimised but also an efficient integration platform for processes from various disciplines – such as architecture and civil engineering – can be provided. By means of an octree-based collision detection resp. consistency assurance a client-server-architecture will be described as well as sophisticated information services for a further support of cooperative work.
The worldwide growth of communication networks and associated technologies provide the basic infrastructure for new ways of executing the engineering process. Collaboration amongst team members seperated in time and location is of particular importance. Two broad themes can be recognized in research pertaining to distributed collaboration. One theme focusses on the technical and technological aspects of distributed work, while the other emphasises human aspects thereof. The case of finite element structural analysis in a distributed collaboratory is examined in this paper. An approach is taken which has its roots in human aspects of the structural analysis task. Based on experience of how structural engineers currently approach and execute this task while utilising standard software designed for use on local workstations only, criteria are stated for a software architechture that could support collaborative structural analysis. Aspects of a pilot application and the results of qualitative performance measurements are discussed.
Building design in Civil Engineering is characterized by the cooperation of experts in multiple disciplines. Close cooperation of engineers in different fields is the basis of high product quality, short development periods and a minimum of investment costs. For each building the engineers have to create a new fire engineering model. The consistent realization of the fire engineering model in all details has high demands on communication, collaboration and building models. Thereby, to preserve the related design models consistent to each other and compatible with the rules of fire engineering is a complex task. In addition, regulations and guidelines vary according to the building location, so the knowledge base must be integrated dynamically into the planning process. This contribution covers the integration of engineers and design models into a cooperation network on the basis of mobile agents. The distributed models of architectural design, structural planning and fire engineering are supported. These models are implemented as XML-based models which can be accessed by mobile agents for information retrieval and for processing tasks. Agents are provided to all planners, they are enabled to check up the distributed design models with the knowledge base of the fire protection regulations,. With the use of such an agent each planner is supported to check up his planning for accordance with the fire protection requirements. The fire-engineering-agent analyzes the design and detects inconsistencies by processing fire protection requirements and design model facts in a rule-based expert system. The possibility to check the planning information at an early state in the sense of compatibility to the fire protection regulations enables a comprehensive diagnosis of the design and the reduction of planning errors.
This paper describes an approach to support co-operation of experts in heterogeneous geotechnical engineering project environments during both regular execution and handling of exceptional situations. A co-operation platform is introduced which is based on a generalized information model mapping key information about the construction project, the construction process as well as the organization structure. Several tools are provided to operate the information model in a network based environment.
The scientific transfer of key technology features to developing countries, together with adequate competence, localisation and adaptation, is the primary purpose of the proposed investigation. It is evident that introducing high-level CAD design and detailing will improve the planning process in developing countries. Successful utilization of applied information technology for the planning process, however, depends on the user-interface of individual software. Therefore, to open the great opportunity embedded in CAD software for clients globally, the language and character-set barrier of traditional user-interfaces must be overcome. A proposal for a research program is given here to address such issue in favour of global civil engineering.