A Method for Estimating Thickness of Sprayed Concrete Layers from Pumped Volume

It is known from experience that when spraying concrete it spreads on the wall, being the distribution of concrete around the axis depending -at the remaining factors constant- on nozzle designo The shape of these "spreadings" have been analysed by different authors [1][2], who shown that...

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Detalhes bibliográficos
Autores: Rodríguez, Ángel, Nabulsi, Samir, Río, Olga
Formato: otro
Fecha de publicación:2010
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/24557
Acesso em linha:http://hdl.handle.net/10261/24557
Access Level:acceso abierto
Palavra-chave:Sprayed concrete
layer thickness
pumped volume
density function
Descrição
Resumo:It is known from experience that when spraying concrete it spreads on the wall, being the distribution of concrete around the axis depending -at the remaining factors constant- on nozzle designo The shape of these "spreadings" have been analysed by different authors [1][2], who shown that a relation between the cross section of single layer strips of sprayed concrete and the spraying process parameters exist. However, no analytical mode1s of this relationship have been found in the literature [1]. The way concrete spreads on the wall can be modelled using a statistical approach by introducing a spraying density function. This [continuous] density function represents the probability of a differential volume of sprayed concrete landing on a differential area around certain coordinates. In this paper a semi-empirical model of the spraying process, based on a parametric family of such density functions is presented. This model allows the estimation of sprayed concrete thickness from operational data (concrete and compressed air flow, distance to wall, nozzle trajectory and actual thickness of sprayed concrete, etc.) The calibration of the main parameters of the model using experimental data is also presented.