Title:
Analysis of L-Box Test for Tremie Pipe Concrete
Author(s):
Habib Alehossein, Karsten Beckhaus, and Martin Larisch
Publication:
Materials Journal
Volume:
109
Issue:
3
Appears on pages(s):
303-312
Keywords:
flowability; Fourier; partial differential equation; plastic yield; slump; spread; viscosity; workability.
DOI:
10.14359/51683820
Date:
5/1/2012
Abstract:
Tremie pipes are used to control concrete flow rate and minimize bleeding and dilution when placed into deep, submerged excavations. The L-box test is designed to measure workability and flowability of tremie pipe concrete as an indirect index measure of concrete viscosity and plastic yield. This test has been simulated by a mathematical model of the representative partial differential equation (PDE) derived for one-, two-, and three dimensional (1-D, 2-D, and 3-D) applications. The L-box model solves a dimensionless PDE in terms of the flow velocity along the L-box channel length as a function of time and distance, which is analogous to a nonhomogeneous heat conduction equation. An example problem for the 1-D application has been solved both numerically (by the finite difference method) and analytically (using Fourier analysis). The two methods and results are comparable and model the concrete flow behavior as observed in standard laboratory L-box tests.