ENGG1100 ENGINEERING DESIGN DOCUMENT 3 of 3 PROJECT C (Movable Bridge) Project Brief Figure 1 Rolling Bridge in London (Heatherwick, 2017) In this document: All the details of the design task for Project C. In Document 1: The semester schedule, a summary of assessment, and where to go for help In Document 2: Assessment details (rubrics, best practice, project specific information etc.)Project C/17 Semester 1 2017 i Table of Contents 1 Project Brief....................................................................................................................... 1 1.1 Introduction............................................................................................................... 1 1.2 Project Scope............................................................................................................. 2 1.3 Bridge Design Requirements ..................................................................................... 2 1.4 The Model.................................................................................................................. 3 1.4.1 Overview.............................................................................................................. 3 1.4.2 Model Materials .................................................................................................. 5 1.4.3 Demo Day requirement ....................................................................................... 5 1.4.4 Abutment Connection Plate (Manufactured Component).................................. 5 2 Demo Day Protocol............................................................................................................ 7 2.1 Overview.................................................................................................................... 7 2.2 Registration ............................................................................................................... 7 2.3 Assembly.................................................................................................................... 7 2.4 Live load test.............................................................................................................. 7 2.5 Serviceability limit load test ...................................................................................... 8 2.6 Site Reinstatement .................................................................................................... 8 3 Safety Requirements ......................................................................................................... 9 References............................................................................................................................... 10 CAVEAT The design scope and specifications may change during semester as more detailed project information becomes available. Changes to design briefs are more common than not in industry, so this adds to the authenticity of the project and allows you to develop those skills necessary to deal with ambiguity and uncertainty.Project C/17 Semester 1 2017 1 N 1 Project Brief 1.1 Introduction As a part of urban future planning, Brisbane City Council has proposed the Oxley Creek Transformation Project. The aim of the project is to develop and enhance a 15 km long corridor from Brisbane River to Larapinta, as shown in Figure 2, into a world class green corridor and leisure landmark. The project will create a major recreational space that affords an improved lifestyle and leisure opportunities for the community and visitors. The Council has committed $15 million over the next four years to this project, and $100 million in total over the next 20 years (BCC, 2017). Figure 2. Oxley Creek corridor from Larapinta to Brisbane River (Google Maps, 2017). The 20-year vision will result in a master-planned lifestyle precinct with improved recreation opportunities such as:  kayaking and canoeing;  trails and walkways;  public aviaries;  'Eat Street' style markets;  urban farms;  sports facilities; and  economic hubs. As part of the Transformation Project, several crossings of the creek and connecting pathways will be required to form part of a traffic management strategy. The exact locations of these crossings and paths are still to be determined but it is proposed that the bridge crossings will connect key areas of the green corridor to adjacent sections of the creek, enabling full use of the area for activity. The bridges must be suitable for pedestrians, cyclists and horse riders. As the bridges and connecting paths are part of a nature corridor, any bridge needs to have a strong aesthetic component and must blend with the natural creek environment. For this Brisbane River Oxley Creek Larapinta NProject C/17 Semester 1 2017 2 reason, the council has specified timber and/or bamboo as the main materials for the bridge. The bridge must also be structurally sound, and durable. The bridge is required to have a movable span as Oxley Creek Transformation Project also incorporates:  opening the creek to increased recreational activities (e.g. kayaking, and boating);  allowing transportation along the creek for maintenance purposes (e.g. dredging, clearing noxious weeds and fallen trees); and  protecting the bridge from unexpectedly high water levels such as might occur with one in one-hundred-year rainfall events (e.g. the 2011 flood). 1.2 Project Scope You will work in a team of five to six students to design a movable pedestrian bridge for Oxley Creek green corridor. Furthermore, you will construct a model of the bridge which will be assembled and tested on Demo Day. At the end of the semester your team will have:  scoped the problem;  outlined the design features necessary to ensure successful use;  researched and evaluated any possible existing solutions;  produced multiple alternative design concepts for evaluation;  used engineering decision making to select one concept for detailed design;  provided proof of concept through construction and testing of a scale model; and  documented your design in a professional engineering report. The problem must be scoped, designed, and built by members of your team. Project leaders, tutors and university technicians can be consulted for specific information, but they will encourage you to wrestle with the problem as opposed to providing answers. This design struggle is purposefully included in the project expectations because it is how learning happens, and it mimics what you will experience in the real world. 1.3 Bridge Design Requirements Your solution must address all of the following design requirements: 1. The bridge shall span a 20 m wide creek at 1.8 m above the average water level which is the datum level for height measurements [NB Bridges are usually designed for a range of water levels as average water heights vary depending on many factors such as seasons, rainfall, and tides.]; 2. It shall allow for passage of pedestrians, wheel chairs, prams, cyclists, and a person riding a horse single file. Thus, the minimum clearance of the deck (footpath) is 2.0 m in width and 3.0 m in height (US Department of Agriculture, 2017). The gradient of the deck of the bridge shall not exceed 1:20 (1 m rise per 20 m horizontal length). There shall be no steps or sudden change in floor level across the span of the bridge; 3. There will be no mid-span supports; the bridge must be entirely supported from each bank; 4. The bridge shall have a movable span to allow for river traffic to pass and to protect the bridge in event of high water level;Project C/17 Semester 1 2017 3 5. When open, the horizontal clearance shall be 16 m centred at the mid-span with a vertical clearance of 5 m measured from the water datum level (i.e. an object measuring 16 m wide x 5 m high must be able to pass through the opening); 6. The bridge shall utilise a mechanism that automates opening and closing of the bridge. [This mechanism is outside the scope of this project and your scale model will be opened and closed manually. However, you will be required to incorporate the concept of automation into your full-scale design although no mechanical design will be necessary]; 7. The abutments on either side of the creek crossing are at an equal height. [The abutments are outside the scope of this work and will be designed by others]; 8. The bridge must provide safety fencing to the standard required for pedestrian and horse trail bridges; 9. The bridge must make efficient use of materials; 10. The bridge shall comprise at least 90% (by volume) timber and/or bamboo and shall blend with the natural environment of the creek. [NB If you have a compelling case for the use of alternative materials, you will need to prepare a single A4 page petition for consideration/ approval by your project leader before proceeding as there are strict penalties for not complying with this material selection constraint. This petition must be made before Week 7.]; and 11. The bridge will have a pleasing aesthetic (as determined by the client) which will be a part of a bridge evaluation process. 1.4 The Model 1.4.1 Overview As proof of concept your team will build a physical model of your movable bridge and demonstrate it on Demo Day in Week 13. Terminology Clarification The following Cambridge Dictionary definitions apply: model something that represents another thing, either as a physical object that is usually smaller than the real object, or as a simple description that can be used in calculations. prototype the first example of something, such as a machine or other industrial product, from which all later forms are developed. Your team will build a physical model of a movable bridge. However, in the context of Document 2: Assessment (The Details), the term prototype should be understood as a synonym of term model. The model is to be built at 1:10 scale. It will be assessed against the following criteria (see Document 2 for the detailed rubric): 1. Materials are used as specified in the brief; 2. Bridge model has aesthetic, innovative design; 3. Bridge model prior to opening and loading has required clearances and gradient; 4. Bridge model prior to opening and loading is stable and can support 50 N (5 kg) load at any point on the deck; 5. Bridge model has smooth finishes and accurately fitting connections;Project C/17 Semester 1 2017 4 6. Bridge model prior to loading opens and closes smoothly; 7. Bridge model is serviceable under live load of 100 N (10 kg) with dimensional requirements satisfied; 8. Materials are used efficiently; and 9. Bridge model after being subjected to load tests opens and closes smoothly and retains required clearances and gradient. The model will be assembled to span between two abutments as shown in Figure 3. The university will provide the abutments. The abutments will have a 5 mm thick mounting plate with four threaded spacers projecting upwards (Figure 4). Spacers are 25 mm high and have a threaded hole. Figure 3. Side view of abutments used on Demo Day (Dimensions in mm) Figure 4. Top view of abutment showing mounting plate and threaded spacers Threaded spacer Mounting plate AbutmentProject C/17 Semester 1 2017 5 1.4.2 Model Materials The full-scale movable bridge should be constructed from timber and/or bamboo. You may use other materials but they should not exceed 10 vol.% of total volume of materials (as stipulated in Section 1.3, item #10). However, for the scale model you may only use materials with density no greater than 600 kg/m3. You may use metal connections, such as screws and hinges, but their total mass must not exceed 500 g. This does not include the connection plates (see Section 1.4.4). If your team finds it necessary to use other materials you can submit a petition to your project leader. The petition must provide a solid argument for the use of a different material, it should be written in a professional manner and it should not exceed one A4 page. A panel of Project C leaders will decide whether to grant or reject the petition. 1.4.3 Demo Day requirement For the purpose of the load test, your model must have a 10 mm diameter hole in the centre of the deck at mid-span. A circular load plate with a diameter of 120 mm will be placed on the bridge deck, the load test cable will pass through the hole and will be pulled downwards from underneath. If you believe that this will affect your bridge stability or load bearing capacity, please consult with your Project Leader for a solution. 1.4.4 Abutment Connection Plate (Manufactured Component) The bridge is to be attached to the mounting plate (Figure 4) via at least one connection plate. The second mounting plate on the right hand side in Figure 3, is optional, depending on your design (i.e. you might choose to fix both ends to the abutments and this will require two connection plates, or you may choose to have only one end fixed). Each team will manufacture at least one connection plate (see Document 2, Manufactured Component). Note that the supplied aluminium plates are not square and you must therefore cut and file them such that the piece is square and machined to dimensions given in Figure 5.Project C/17 Semester 1 2017 6 Figure 5. Schematic of connection plate - Manufactured ComponentProject C/17 Semester 1 2017 7 2 Demo Day Protocol 2.1 Overview Assembly and testing of models will take place in Week 13. More details will be made available closer to the date. Spectators are welcome provided they stay away from the testing area and do not interfere in any way. Assessment crews will assess all models as per the marking details contained in Document 2: Assessment (The Details), Section 8.5.3. 2.2 Registration Upon arrival, teams will proceed to the registration desk. Your model shall be packed in a way that allows simple handling and weighing. Small parts should be put into bags or taped together. You must provide a list of components stating:  component name,  quantity,  material,  density,  mass, and  volume. Your team must bring all tools required for assembly with you on Demo Day. Use of power tools is not allowed. At the registration desk your model will be inspected for: 1. total mass of the model; 2. density of used materials; and 3. mass of components with density larger than 600 kg/m3, excluding the connection plates [NB If connection plates are attached to the bridge deck, then a weight will be assumed and deducted]. You will receive an assessment sheet and you will be allocated an assembly station. 2.3 Assembly At each assembly station, there will be a pair of abutments with a 2 m void in between as shown in Figure 3. The stations will be accessible for two (2) hours prior to the time that your model is scheduled to be tested. Teams may use all or part of this time to set up their models but models must be completely assembled by the scheduled time for testing. You are however encouraged to make your model quick and easy to construct. 2.4 Live load test As per the design specification, your bridge should support a live load of at least 10 N (10 kg). To test this on Demonstration Day, a vertical load will be applied in the centre of the deck at mid-span. A circular load plate with a diameter of 120 mm will be placed on the bridge deck and pulled down by a cable from underneath the module. The load will be increased gradually up to live load of 10 N (10 kg) at which point, the following requirements will be checked:Project C/17 Semester 1 2017 8  the bridge continues to span the 2 m void;  the lateral clearance on the deck is  200 mm;  the head clearance is above the deck  300 mm;  the gradient across the deck is  1:20, and  the clearance from water datum level (Figure 3)  180 mm. The dimensional requirements apply over the full length of the bridge and will be checked by passing a 200 mm wide  300 mm high test block across the deck. 2.5 Serviceability limit load test After the live load test, the load will be increased to the serviceability limit load which is the maximum load at which dimensional requirements stated in Section 2.4 are still met. Terminology Clarification Serviceability limit refers to the set of conditions under which a structure is still useful. The load at which a structure breaks is known as the ultimate load. 2.6 Site Reinstatement After completion of all tests, each team must disassemble their model and return the site to as near a pristine condition as possible. You need to make sure to collect all parts of the kit, including tools, screws, and instructions. No rubbish or pieces of models are to be left behind and everything brought by each team to the site must be removed.Project C/17 Semester 1 2017 9 3 Safety Requirements You and your team must comply with the following safety requirements. 1. On campus, manufacturing may only be undertaken in the ABB Student Technology Centre (ABB STC). Inductions for the ABB STC must be done online before you can enter the workshop. Full details are available on Blackboard at: Learning Resources > Manufactured Component. 2. Your team must undertake a Build Risk Assessment for building your model as part of the Project Scheduling Package (PSP) due in Week 5. No model making, assembly or testing will be permitted until your tutor has received and signed a hard copy of this risk assessment document as part of your PSP. 3. The following personal protection equipment must be worn at all times during demo day activities:  enclosed shoes,  safety glasses to be carried and used if required, and  work gloves to be carried and used if required.Project C/17 Semester 1 2017 10 References BCC (2017). Oxley Creek Transformation Project, Brisbane City Council. Retrieved 06/02/2017 from https://www.brisbane.qld.gov.au/environment-waste/naturalenvironment/brisbanes-creeks-rivers/protect-our-waterways/oxley-creektransformation-project Google maps (2017). Earth map of Oxley Creek catchment. Retrieved 16/02/2017 from https://www.google.com.au/maps/@-27.5961587,153.0152881,18894m/data=!3m1!1e3 Heatherwick (2017). Rolling Bridge, Heatherwick Studio. Retrieved 06/02/2017 from http://www.heatherwick.com/rolling-bridge/ United States Department of Agriculture (2017). Equestrian Design Guidebook. Retrieved 08/02/2017 from https://www.fs.fed.us/t-d/pubs/htmlpubs/htm07232816/page10.htm