Designing, building and testing a timber bridge model

Make groups of 4 students. Discuss together about the aim of the assignment and what needs to be done in order to successfully complete it. Think ahead to all stages of the project and appoint each student one activity, that they will be responsible for. PS. Each student will not complete their topic alone, instead he/she is responsible for organizing works, so that the topic gets done. The responsibility areas may be all, some or more then the following:

• ensuring the execution of the whole project (project manager);

• design (structural engineer);

• cost estimation (quantity surveyor);

• building process & safety (construction manager);

• the report;

• the presentation.

The bridge model must meet the following parameters:

• span: s = 2550 mm;

• max. width: b = 500 mm;

• max. height: h = 800 mm;

• max. length: L = 2900 mm;

• the model must have a planar bridge deck with a minimum width of 300 mm;

• there must be a free height of 200 mm on the deck in the whole length of the bridge;

• in the center of the bridge there must be a free area of 300 × 300 mm (on top of the bridge deck) to be able to apply the load;

• the model must be in one piece and be movable;

• fixing the model to the supports is not allowed;

• it is not allowed to direct the horizontal support reactions to the supports, and it must be ensured, that any part of the bridge that is lower than the support surface will not touch the support when it deforms - for this, a free gap of 20 mm must be ensured between the support and element.

The bridge model design must be documented on A3 sized drawings. The building process may only be carried out based on drawings on paper (not using a computer) thus, the drawings must be in such detail, that it would be possible to build the bridge model based on them. The building permit will be given when You have presented Your design drawings and they have been approved. It may also be necessary to make improvements to get the approval.

The drawings must include:

• side view;

• end view;

• bottom view;

• top view;

• cross-section;

• longitudinal section;

• drawings of at least three joints;

• specification of all details (number of details, their shape and dimensions);

• if you have created a 3D model, then views of it.

When formatting the drawing the following requirements must be met:

• all parameters/dimensions set in the assignment must be pointed out on the drawings (e.g. span, min/max heights etc);

• the drawings must have enough dimensions added on them, that it would be possible to build the bridge without having to additionally check the digital drawing file;

• dimensions must be formatted with the colour Magenta;

• sections must be formatted so, that elements that are in the section have a bigger lineweight than those that are not “being cut”;

• section positions and joint locations must be marked on the drawings;

• all drawing parts must be named and have their scale given (e.g. M1:10).

• Wear suitable work clothes, protective footwear, headgear and other personal protective equipment when working.

• Before starting work, remove any objects that may be caught between the rotating or moving parts of the machine (ties, watches, chains, rings). Workwear cuffs must be buttoned.

• Before starting the machine or machine tool, check that it is in working order, that it has protective covers and restraints and that it is safe to do so.

• If machining of parts can result in volatile chips or dust and the bench does not have any special fixed protective equipment, goggles or a transparent screen should be used.

• Use headphones to protect against noise.

• Inhalation of fine dust into the airways is protected by a disposable dust mask

• Do not lean on a working machine or machine bench.

• Oil, grease or other fluids which have come into contact with the floor during operation must be removed immediately.

• The machine must be disconnected from the mains before leaving the workplace and in the event of a power failure.

• If the metal parts of the machine tool are energized (electrical current can be felt), the machine must be switched off immediately and the responsible person informed.

• If an emergency occurs, use the Emergency Stop button, if available.

• Work must be carried out in a safe manner. Evaluate the potential risks involved in the work phase and, if necessary, take measures to prevent them.

• After completion of the work, the workplace must be reorganized, the tools and aids put in the designated areas.

• Any defects or malfunctions during working hours must be reported to the laboratory engineer.

During the building phase the following should be done:

• count the actual quantities of materials used and the actual time spent;

• take photos in different phases of the building stage;

• make appropriate notes on what and why was changed in the design during the building process.

When writing a laboratory report, clear, concise, and formal technical language must be used. The report must be written in the third person and past tense, as it describes work that has already been completed. Sentences should be precise and objective, avoiding personal opinions or informal expressions. Each section—such as the introduction, methodology, results, and discussion—should be clearly labelled and logically organized to ensure readability. Figures, tables, and graphs must be properly numbered, titled, and referenced in the text. Units of measurement should follow standard SI conventions, and all data or calculations must be presented neatly and accurately. Finally, the report should maintain a professional tone, demonstrating both technical understanding and attention to detail.

The report must be well thought through, and the reader must be enlightened with information of what was the initial assignment, what was done and achieved. A good report is informative and gives a complete overview of the materials and the process. It should be comprised of the introduction, the main body text, and the conclusion.