Keywords: finite element model, homologation procedures, prestressed concrete sleeper, total strain fixed crack model, DIANA.

This paper demonstrates a quasi-static homologation procedure for prestressed concrete sleepers using the DIANA finite element software package. Conventionally, the procedure involves monitoring the crack initiation and propagation on the surface of a concrete sleeper at different loading states using a graduated microscope [1]. The use of a graduated microscope in monitoring cracks on the surface of a concrete sleeper is technically tedious and time consuming. Furthermore, the approach does not give a correct apprehension of the damage mechanisms, which leads to the failure of the structure, as a result of the heterogeneous nature of the concrete.

With this background, a finite element modelling technique focused on a given region of the loaded specimen was adopted with the emphasis on predicting crack initiation and propagation within a reasonable accuracy.

The quasi-static homologation procedure for concrete sleepers at the rail seat [2,3] was simulated with the use of DIANA's total strain-fixed crack model [4]. A full-scale finite element model of prestressed concrete sleeper type M41 was developed using the CHX60 solid elements in which the compressive crushing of concrete and the concrete cracking in the tension zone were taken into account with a non-linear stress-strain relationship. The degradation of compressive strength arising from the tensile damage in the lateral direction was also taken into account using the CEB-FIP model code 1990 [5]. The behaviour of the prestressing steel was considered with a multilinear work hardening constitutive model.

In conclusion, the predicted load-crack evolution of the sleeper were found to be in good agreement with the test results. In addition the capacity of the sleeper was predicted with reasonable accuracy. The experience of working with the total strain-fixed crack model was rather good in regard to the stability of the numerical procedure.

1

EN 13230-2, "Railway applications - Track - Concrete sleepers and bearers - Part 2: Prestressed monoblock sleepers", 2002.

2

E. Heylen, et al., "Techniques in Detailing, Fabrication and Laying of Conrete Monoblock Sleepers", Infrabel NV, 2006.

3

prEN 13230, "Railway applications - Track - Concrete sleepers and bearers - Parts 1 and 2", 2007.

4

J. Manie, W.P. Kikstra, "DIANA User's manual release 9.4.3", TNO DIANA BV, The Netherlands, 2010.

5

CEB-FIP, "CEB-FIP Model Code 1990", Comité Euro- International du Béton, 1991.

purchase the full-text of this paper (price £20)

go to the previous paper
go to the next paper
return to the table of contents
return to the book description
purchase this book (price £110 +P&P)