Roads and Bridges - Drogi i Mosty
14, 1, 2015, 19-29

Influence of loading time on subgrade parameters derived from VSS static plate test

Piotr Mackiewicz Mail
Wrocław University of Technology, Faculty of Civil Engineering
Bartłomiej Krawczyk Mail
Wrocław University of Technology, Faculty of Civil Engineering
Published: 2015-04-22

Abstract

Achieving the required bearing capacity of a road subgrade during VSS static plate measurements is very often problematic in the contemporary road engineering execution. The problems arise during the test due to passing over a viscous-plastic characteristics of material. The fact remains that only elastic properties of material are being analyzed in the commonly applied measurement practice which does not give a full picture of tested subgrade, especially in case of a subgrade with a limited bearing capacity. Therefore the authors examined the impact of loading and unloading times in the VSS test on registered vertical deflections and the estimated bearing capacity of the examined subgrade. Consequently, the appropriate calculations not only have acknowledged the viscous-plastic component of displacements, but also have disclosed some significant differences in results of deflections, and values of primary and secondary moduli, depending on the time of testing. Moreover, the drawn up 3D model using the Finite Element Method (FEM) has been verified in real field testing.

Keywords


deformation modulus, elastic modulus, FEM, loading time, subgrade parameters change, viscous-plastic model, VSS

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References


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Influence of loading time on subgrade parameters derived from VSS static plate test

  
Mackiewicz, Piotr; Krawczyk, Bartłomiej. Influence of loading time on subgrade parameters derived from VSS static plate test. Roads and Bridges - Drogi i Mosty, [S.l.], v. 14, n. 1, p. 19-29, apr. 2015. ISSN 2449-769X. Available at: <>. Date accessed: 29 Oct. 2020. doi:http://dx.doi.org/10.7409/rabdim.015.002.