Educational CD-ROM gives an overview and aids in design

Transcription

1 Educational CD-ROM gives an overview and aids in design Sigrist, Christophe 1, Brunner, Roland 2 ABSTRACT Since 1997, the Department for Research and Development at the Swiss School of Engineering for the Wood Industry (SWOOD) in Biel, Switzerland, is involved in a project the aim of which is to develop a multimedia educational instrument about new technologies in the wood and furniture industries. Employees, teachers and students are to be given the opportunity to revise their knowledge and to further improve their education through self-study. The aim is to offer easy access to know-how in various fields and the user to get a good overview of the many possibilities for design and construction using timber. Three CD-ROM have been designed: Numerical Control, Stains and Varnishes, and Timber Constructions. All CD-ROM offer information at basic and expert level. They also offer the user the possibility to check her / his understanding with accompanying tests. The first CD Numerical Control gives general explanations to CNC technology, basic information about programming, explains the programming languages, shows the different possibilities for programming, and offers a catalogue for machines. The second CD Stains and Varnishes contains general information on the different timber species as well as on surface coating, details about the required machines, detailed information on stains and varnishes and relevant recommendations for their application. The third CD-ROM Timber Constructions firstly presents the topics related to timber houses treating the different building systems as well as the types of wall, deck, roof and façade systems on the market. With regard to structural timber engineering the user will find secondly information on the basic principles of loadbearing and bracing systems as well as an overview of connectors and joints. There is also a general section, which gives information about the profession of the timber engineer, which presents different structural materials and informs about measures in timber protection. The success of these CD-ROM prototypes will show how - and if! - this medium can help to cover the need of the wood industry for further education. Since it is - to our knowledge - the first such project of the European wood industry, it is hoped to realize the predicted success, which similar projects may have in the future. THE PROJECT The goal was to develop a multimedia educational instrument about new technologies in the wood and furniture industries. Employees, teachers and students are to be given the opportunity to revise their knowledge and to further improve their education through self-study. The aim is to offer easy access to know-how in various fields and the user to get a good overview of the many possibilities for design and construction using timber. Ten partners of EUROLIGNA (Association of the European wood industry) worked on this project under the direction of AIDIMA in Spain. The European professional educational program Leonardo da Vinci financed it. THE THREE CD-ROM Three CD-ROM have been designed with the titles: 1 st : Using and programming NC machines in the timber and furniture industries, 2 nd : Wood staining and varnishing and 3 rd : Timber construction. All CD-ROM promote the self-training at the workplace and they include basic and specific knowledge. 1 Professor, Dept. of Engineering, Swiss School of Engineering for the Wood Industry (SWOOD), Solothurnstrasse 102, 2504 Biel-Bienne, Switzerland 2 Research engineer, Dept. of Research and Development, Swiss School of Engineering for the Wood Industry (SWOOD), Solothurnstrasse 102, 2504 Biel-Bienne, Switzerland

2 The CD-ROM Timber construction deals with the subjects of timber houses of different building systems. With regard to structural timber engineering the user will find information on the basic principles of load-bearing and bracing systems. For basic information there is a section that presents different structural materials, another gives an overview of the connectors and wood connections and further sections inform about timber protection measures. This CD aims to address companies of timber construction, architects and engineers active in timber construction, technical professors of all levels and students of technical and professional schools. The CD-ROM Using and programming NC machines in the timber and furniture industries gives explanations with regard to CNC technology, basic information about programming, explains the programming languages, shows the different possibilities for programming and offers a catalogue for machines. The target audience of this CD-ROM are cabinetmakers, joiners, technical professors of all levels, students of technical and professional schools and partially apprentices. The CD-ROM Wood staining and varnishing contains an overview of different timber species, means of surface coating, details about the required machines, the descriptions of stains and varnishes and recommendations for their application. A list of faults with respect to the application of stains and varnishes as well as a list of controls for quality are presented. The contents aim to reach woodworking companies, technical professors of all levels, students of the technical and professional schools and partially apprentices. Fig. 1: The content of the three CD THE STRUCTURE OF THE CD-ROM TIMBER CONSTRUCTION In the following sections only the CD dealing with topics on timber construction is presented. The design of the CD and the topics that are treated are briefly discussed and presented. The presentation follows the different possibilities to the user exploring the CD. The range of topics of the CD ROM is represented on the main window. From the connecting devices and connections to wood preservation and the building materials used in timber construction all main topics are presented. Wood construction systems and the engineering of wood construction can be selected for study and / or information. Fig. 2: The main frame of the CD Timber Construction

3 The topic on engineering of wood connections contains an introduction transferring the basic knowledge on connections and the effects of the connecting devices on the timber structure to the user. Additionally the different connecting devices showing their geometry and their processing are presented. The application of the different connectors is shown presenting built examples. The possibilities of joints not requiring mechanical connectors are shown discussing the topic of wood to wood connections. Carpenter type joints connecting timber in the longitudinal and perpendicular direction placed in one or various layers are presented in theory and shown by built examples. The effect of local stresses, misalignments, notches and more are discussed. The chapter on wood preservation considers the requirements for durability of the timber and the possibilities of wood preservation. Firstly the critical areas in a construction are highlighted and various solutions in terms of selection of species and constructive means to enhance the durability of timber are presented. Then the different possibilities of wood preservation are presented and what substances the solutions contain are discussed. Possible applications are shown by various examples. Fig. 3: Selected topics of the CD

4 Materials and products or product groups used in timber construction are presented. More and more wood based materials appear on the market and it is difficult to select the right material for the right application. Board type materials (panels) and beam type materials are separated into two classes. Special products issuing from a combination of these products or their combination with solid timber are also presented in this chapter. Again reference to many applications and built projects are given here. Timber structures in general and timber homes in particular must be carefully designed and detailed. Compared to other building materials additional materials to treat thermal insulation, sound insulation and to enhance the durability of timber must be selected carefully and must be brought in combination with the structurally used timber. The detailed description of current products, qualitative characteristics and their application are presented. The chapter dealing with timber construction systems presents the bases with respect to constructive requirements shows the different construction systems used in floor, roof and wall systems. The timber construction systems are specified showing their construction principles, the realisation of the relevant connections, the possibilities of bracing capacity and the cross sections typically used in these systems. Several examples are given to enhance the understanding of the differences between the current systems. Fig. 3: Selected topic of the CD cont.

5 The development of timber structures and its engineering aspect represent one of the main topics of the CD. Specific themes with detailed information are linked to this topic. A brief overview on the history of timber construction in general and outstanding engineered timber structures in particular is given. Special topics dealing with the duties of timber engineers, areas with potential for timber constructions, the presentation of frequently used construction members and solutions related to the stabilisation of timber structures may be selected. The most effective structures in view of carrying horizontal and vertical loads to the supports are shown. Their application and relation to the stiffening of timber structures is presented. As mostly beam type members are used in timber construction the transmission of forces must be carefully analysed resulting on a distinct and hierarchical arrangement of load carrying members. The translation of the static models into a built solution must be analysed and executed carefully. Reference to different engineered structures is given. Basic solutions for standard load bearing members are given and discussed in detail. From simply supported beams, continuous beams, frames to trusses and grid structures various solutions are treated. The fields of application in order to best use the strength of the timber for different systems, the forces to be taken and indications with respect to the valid design rules are given. Their application in realized timber structures is documented by several examples. Fig. 4: A selected topic and linked specific information. The last main topic of the main menu is presented at the top of the above figure. As for the other topics various subchapters are available for more detailed information as shown above for the case of engineered wood construction. Keywords lead the user through the CD to more expert information and specific know-how.

6 HOW TO WORK WITH THE CD ROM The concept of this CD-ROM is set in such a way that the topics may be handled individually. The photographs and graphs usually represent practical applications on the basis of reference objects. This means that each topic is linked to a common background composed by several objects which are completely described in terms of structure, structural members, stabilization system, joint system and connectors, wood preservation and more. The following two examples illustrate two possibilities of using the CD: the transfer of know-how for a particular topic, and the use of a specific chapter in view of developing a possible solution to an unknown problem. The first example below shows the example of someone who would like to get information with respect to the selection of suitable materials for a structure with specific durability requirements, the application of such materials and the means of possible wood preservation for the selected condition. Via the specification considering the hazard categories and the required or desired durability of untreated and treated materials the user finds possible solutions for his problem on the bases of project description. Not only an educational effect is given by the use of the CD but it also plays the role of know-how transfer. Fig. 5: Educational effect and know-how transfer of the CD

7 Solutions to connect small size timber members are desired. Under the label of connectors showing small penetration depths several possibilities are presented in detail. The selection of nail plates may lead the user to built examples using nail plates. The geometry of the connectors and the required timber size, the working behaviour of the selected joint, the possible fields of application and the limits of such solutions are discussed in detail. In realized projects the user finds an example, where a very similar solution to the defined problem is shown. The application of the considered type of connector in realised projects may indicate the feasibility of such proposals. An appreciation of the solutions, the comparison to the problem to be solved and the investigation if such connections are available locally may lead to a similar solution. Next to the specific and searched information on connectors and joints general information with respect to the project, to special frame systems and stabilization are found here. After completion of the research the user is lead back again to the main frame. Fig. 5 : Developing detail solutions using the CD

8 The second example above indicates how joint solutions may be developed using the CD as a source of information and documented structures. Other construction problems may be handled in a similar way. ACCEPTANCE ON THE MARKET Testing of the prototypes The first prototypes of the CD-ROM Timber construction were tested in classes of the Swiss School of Engineering for the Wood industry. In first tests the usability of the CD was tested by means of set tasks, problem definitions and tests. At the end of the test phase the students judged the CD-ROM by a questionnaire. From these results the acceptance of the CD-ROM was measured and the potential on the market deduced. A class of the post-graduate students in timber construction with a basic training in architecture or civil engineering also participated on these tests. The selected students represent the ideal test persons since they will take leading positions in the timber economy corresponding to a large part of the target audience. Next to the contents persons of different levels of knowledge could also check the comprehensibility. From the feedback of the test persons the necessary modifications of the prototypes followed. The overall evaluation of the CD-ROM showed that the contents profit from the clear and easily understandable structure. Accordingly this positively affects the methodology as the handling of the CD very strongly corresponds to an encyclopaedia. A largely discrepant opinion existed in the user friendliness and the interactivity of the program. The evaluations oscillated between poor and very good, whereby the different opinions probably considerably depended of the experience of the users with this type of media. Another substantial weak point was felt to be the poor integration of the control of the learning process. Nevertheless all users could evaluate the test as instructive as all test persons could easily adapt to the user-friendly program structure. Success of sales The sales started in mid The selling is regionally organized by the EUROLIGNA meaning that each partner can sell within the EUROLIGNA - space within its country only. In Switzerland the selling takes place by the recognized federations, which have a technical book selling facility. A first estimation of the success of sales will take place in the beginning of Further developments In mid 2000 a project with the title "Medium-didactical and Internet-based advancement of a learning module in the area of engineered timber construction" was handed in and approved. The target is to develop the sections regarding engineered timber construction from the CD-ROM to a teaching / learning unit suited for self studies and distance learning in a first step. In summer 2001 a learning module should be available for teaching, for the development of knowledge, for the transfer of know-how, as a checklists for the construction and as an administration of the sources of knowledge. CONCLUSIONS From January 1997 to November 1999 a multimedia learning instrument was developed with different topics related to timber construction for the timber and furniture industry. Partners from all over Europe: France, Spain, England, Germany, Finland, Belgium and Switzerland produced 3 CD covering the fields of furniture production, timber housing and engineered timber structures. The Swiss School of Engineering (SH-Holz or swood) was responsible for the preparation of the topic engineered timber structures. The CD which are available today allow the user to gain an overview of the state of the art in the field of usage of timber be this structurally or non structurally. Modern methods of presentation, video sequences and a substantial photographic background lead to an attractive learning / teaching instrument. Links to information sources, Internet addresses and more make it to a valuable source of information for practicing engineers and architects as well. The CD are structured in such a way to be extended, corrected and adapted at any time to finally become an expert system for several levels of professional users. Depending on the goals to be achieved the present version of the CD is not suitable for distance learning or self studies. The main goals and the main topics in view of this issue will be redefined in the near future. Furthermore the contents will be optimized with respect to methodology and didactics in view of dissemination via digital media. The following steps will be undertaken as soon as possible: definition of contents suitable for distant teaching, the adaptation and improvement of existing topics and contents, the formulation of main goals and possible sequences considering methodic and didactic rules, implementation into an interactive learning module, the selection of attractive types of media, the selection of the type of guidance of the students and the integration into media supports as internet, CD or similar.