Design & Build Project

University of Bristol

Department of Civil Engineering

Design 1C – Design & Build Project

Purpose

To design, draw, build and test a model structure of least weight from given materials, to carry a load of 5kN at the centre of a span of 750mm.

Materials

2No lengths (6m each) of aluminium angle (properties attached), 1 length (6m) of aluminium flat (properties attached), Aluminium sheet 1.6mm thickness, 4mm bolts (4.3mm clearance holes).

Performance requirements

1. Each structure must carry a load of 5kN (0.5 tonne) at the centre of a span of 750mm.

2.         The width of the structure should not exceed 300 mm.

3.         The height of the structure should not exceed 350 mm.

4.         No part of the structure may be below the level of the supports.

5.         Each structure must be such that a steel bar of 19mm diameter may be positioned through the structure at a central span, and at a centre-line height of not more than 40mm above the supports. This is to enable the load to be applied to the structure.

Performance

The winning group will be the one which produces a structure which complies with the above specification and which has the minimum value of the following value function:

Weight of structure in grams + number of bolts used

Discussion

Students will work in laboratory groups. Each group will be expected to discuss and decide the form of their structure, and to analyse it using simple statics.

During two afternoons in the small structures laboratory, each group will be expected to finish off their designs and drawings and to build the completed structure.

The structures will be tested in the Design class of week 18 in the Spring Term – but this date will be confirmed nearer the time.

Assessment

1. Each student must produce a short written report on the design logic, analysis and form of failure of the model (~6-8 pages) including diagrams. The report will be submitted along with a drawing of the bridge at the end of the second term. Make sure you take enough notes during the laboratory class to enable you to write up your ideas later in the year.  Further details will be given during the 1st laboratory session

2. Each group should also record the main dimensions and details of their structure so that they can produce a formal technical drawing of it in a later project.