Concreto projetado como revestimento de túneis na Ferrovia Norte-Sul: análise segundo parâmetros de durabilidade
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Data
2010-09-24
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Universidade Federal de Goiás
Resumo
The present work aims to analyse the durability parameters of the shotcrete,
comparing the dry and wet projection systems, of the concrete resulting from the projection in
plates and from the test specimens extracted from the tunnels structures of the North-South
Railway, tract 01, in Anápolis-GO.
This work considers an experimental research concerning the shotcrete behavior for
dry-mix and wet-mix projection systems, by using testing indicators of the main durability
parameters coming from national and international specifications. So, the experimental
program involves a comparative assessment among the projection systems of current use in
shotcrete, considering the comparative analysis between projected plates (control) and
extracted test specimens from the tunnels on what refers to meeting the requirements related
to durability.
Therefore, the experimental program showed as independent variables: type of
projection system (whether by means of dry-mix or wet-mix shotcrete) and the extraction of
test specimen (from the control plates or from the tunnels structure). For each type of
projection (dry-mix and wet-mix shotcrete), three plates were cast (normally used for concrete
technological control) in conditions similar to the work-site, with the test specimens
extraction been carried out according to pre-established ages. Eight test specimens were
extracted from the just-builts tunnels generating thus samples to the durability associated
tests, such as: capillary water absorption, immersion water absorption, concrete electric
resistivity, water penetration under pressure, penetrability of chloride ions and concrete
compressive strenght. Test specimens extracted from the tunnels and the from the plates were
also submitted to testings of compressive strenght and mix-proportion reconstruction.
The concrete extracted from tunnels showed worse results comparing to the
parameters expected from the projected concrete requirements for road and rail tunnels, and it
also demonstrated results which were inferior to the ones obtained from the plates. From a
general assessment view, we could verify losses of durability properties of the shotcrete
extracted from tunnels in reference to the projected plates.
Descrição
Citação
MENESES, Antônio Davi Barbosa de. Shotcrete tunnel lining as the Railroad
North-South: second analysis parameters
durability. 2010. 166 f. Dissertação (Mestrado em Engenharias) - Universidade Federal de Goiás, Goiânia, 2010.