Minimum Cost Design of one-Way TRC/RC composite slabs

Title: Minimum Cost Design of one-Way TRC/RC composite slabs
Author(s): I. Papantoniou, C. Papanicolaou
Paper category : conference
Book title: International RILEM Conference on Material Science
Editor(s): W. Brameshuber
Print-ISBN: 978-2-35158-106-3
e-ISBN: 978-2-35158-107-0
Publisher: RILEM Publications SARL
Publication year: 2010
Pages: 165 - 175
Total Pages: 11
Nb references: 8
Language: English

Abstract: The present study presents the outline and the results of an optimum (minimum cost) design procedure for one-way RC slabs cast on top of prefabricated Textile Reinforced Concrete (TRC) Stay-in-Place (SiP) formwork elements. The SiP element is considered to participate to the load-bearing behaviour of the composite slab. Such slabs may be used as superstructure systems for short and medium-span bridges and industrial or marine buildings (for example, used transversely spanning between longitudinal girders). The procedure is decomposed in two design states: a temporary and a permanent one. During the temporary state the TRC element is designed to undertake construction loads, as well as the self-weight of the fresh cast in-situ concrete. During the permanent state the design addresses the behaviour of TRC/RC composite slab. Design equations conform largely to Eurocode 2. Materials’ cost functions (for textiles, steel, formwork’s micro-concrete and cast in-situ concrete) have been derived and are presented in the paper. The design variables vector includes the geometry of the TRC formwork (different cross-sections are examined), the fibre and steel reinforcement ratios, the fibre material for the textile reinforcement (grids considered are of rovings’ orthogonal configuration) and the flexural strength of the microconcrete in the SiP formwork. The optimum determination of the design variables leads to the minimum production cost of the composite slab, while fulfilling simultaneously: (i) Serviceability Limit State (SLS) and Ultimate Limit State (ULS) design criteria (for both design states); (ii) Geometric constraints based on construction rules and anthropometric data; and (iii) General design rules (e.g. desirable mode of failure). Preliminary results indicate that (the over-conservative) SLS governs the optimum design. Cap-shaped TRC formwork crosssections with micro-concretes of moderate tensile strength seem to be favoured.

Online publication: 2010-10-21
Publication type : full_text
Public price (Euros): 0.00