Prestressed slabs of the Exploitation Centre at Blécherette Municipality of Mont-sur-Lausanne - Switzerland

Abstract

The construction of this Centre at Blécherette that consists of approximately 10,500 m² of slabs on columns, used as a platform by the automobile traffic, has made it possible to achieve a prestressed concrete structure displaying the following characteristics: — density, — support of the loads of the road-bridges, — tolerance of the limited deformations, in spite of a rapid forms dismtanling. If the execution problems deal with the study and the choice of concrete, as well as with the establishment of a detailed working programme, the work of the engineer has been very related to the super-imposed loads, which, in the beginning, excluded the use of the semi-empirical methods. The calculations have been carried out with a certain amount of analogy in comparison to for instance those of a plate-bridge, but with all the bi-directional elements [continuity, prestressed, mobility and distribution of the loads). Thanks to the computer, and after some experimenting, the dimensioning of the prestressed parts and verification of the bending stresses developed in a normal manner. On the other hand, the minute one enters into the control of the punching of the slab and into that of safety against breaking, one enters into a most complex field, where, due to lack of more profound research or tests on models, the traditional methods have to be adapted with intuition and good common sense.