School/work alternation: METRO C and ROME’s ISTITUTO PER GEOMETRI FEDERICO CAFFÈ. a day in the lab.
The school/work alternation project involved Metro C S.c.p.A.’s engineers, surveyors, and employees in organising meetings, face-to-face lessons, presentations, practical drills, and work site tours. All this was to allow approximately 20 students from Rome’s Istituto per Geometri Federico Caffè to have a unique educational experience that will be of use in their future careers.
Every morning starting at 8:30, from 12 to 16 June, the students visited Metro C’s main office to try their skills in a number of tests, simulations, and drills.
The day we are recounting here is one in which they were presented with a special challenge: learning the analysis techniques for the materials designed within the Laboratorio dei Materiali di Metro C.Here, the youths had the opportunity to test the knowledge acquired in the field by working alongside lab workers for a whole day.
The first test they witnessed was the sieve analysis. The test consists of using a series of sieves to divide the material into numerous particle-size classes of decreasing size.
The mass of the particles collected in the various sieves is brought in relation to the material’s initial mass. The cumulative percentages of what passes through each sieve are recorded in numerical form and, if required, represented in the form of a graph.
The subsequent analysed phase is the curing of cubes of concrete, done for Metro C for every 100 cubic metres of casting. The cubes made after 24 hours are brought to the laboratory and are positioned inside standard tanks, at a controlled temperature and at 100% humidity. The temperature is controlled using temperature probes which, if needed, allow the water to be heated using resistances for this purpose.
The cubes are allowed to cure inside the tanks, and are then delivered before 28 days to the official laboratories, which issue an official certificate with the declaration of the mechanical strength value.
Already before the 28 official days, Metro C checks daily production. In fact, the cubes’ mechanical strength is constantly assessed for the construction of the concrete curing curves.
Another test viewed by the students is the slump test, which uses a slump cone to determine the consistency of the fresh concrete.
Fresh concrete is tamped in a conical frustum. The mould is lifted upwards and the slumping of the sample provides a measurement of the concrete’s consistency.
The final test the youths witnessed was the compression of the concrete cubes in a mechanical press, where a force is pressed upon a cubic specimen until it breaks, thus obtaining the concrete’s relative mechanical resistance to compression. At the end, there was some analysis of the steel arriving at the laboratory, with recognition of the trademark and the first quality controls prior to sending the samples to the official laboratory.
