Development, conception and industrialization of innovative products: A set of tools useful to easily cast on-site concrete stairs

Abstract: The profession of staircase builder is a hard job. Technically complex, it requires solid skills and certain know-how to get good quality results and to be able to compete commercially with low-cost precast stair manufacturers. Towards the expansion of that discount market, the trade of traditional construction has evolved a lot over the past few years. For sake of optimizing Cost-Quality-Delivery criterions, Choquet Co., the company I have worked with has practiced continuous improvement for more than a decade, making strategic decisions to find the best concept for stairs construction. The present study returns to all the history of concrete staircase building, the improvements made or to make to ease the realizations of those constructions, to get high finish grade and accelerate the proceedings. In fact, despite the expansion of our technologies and of our control on materials, this trade remains hard to handle and is often realized by unskilled masons and in an archaic way. This can be explain culturally by the fact that the building trade is in France a family tradition, developed on very old uses that people of this world tend to keep alive. The main part of the study is about the conception of innovative mechanisms aiming at the realization of formworks for straight and winder stairs. A particular attention has been dedicated to mechanical issues, choice of materials and technological solutions to face problems which include robustness, fatigue, weight, reliability and fouling matters. Starting the conception procedure by ideas, drafts and inventive drives, we then produced set of specifications to segment and delimit the requirements of our relative products. Afterwards, we could start the design by realizing some easy models from which we could evaluate the future lacks and so the fields in need of more accurate studies. FEM analyses have been performed on the key parts of the mechanism, so that we could refine some geometrical and material parameters. In addition, a presentation will be made individually on all the set of tools thought to be parts of the equipments of the perfect staircase builder. From moulds to the workshop truck, it is a real concept of a profession that is still not recognized in a world that is pretty hard to invest but that could bring a real change in the way to build in the future.