Efficient meso-scale homogenisation and statistical size effect analysis of concrete modelled by scaled boundary finite element polygons. (1st October 2017)

• Record Type: Journal Article
• Authors: Wang, Z.M.; Huang, Y.J.; Yang, Z.J.; Liu, G.H.; Wang, F.
• Is Part Of: Construction & building materials. Volume 151(2017)
• Page Start: 449
• Page End: 463
• Publication Date: 2017-10-01
• Subjects: Homogenisation -- Scaled boundary finite element method -- Meso-scale modelling -- Concrete -- Size effect -- Monte Carlo simulations; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2017.06.095
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Develop a new homogenisation approach using SBFE polygons for meso-models of concrete. Demonstrate much improved accuracy and considerable reduction in DOFs over the FEM. Propose a Weibull-like size effect law of effective elastic moduli considering porosity. The critical RVE size is 4.5 times the maximum aggregate size. Abstract: This study develops an efficient numerical homogenisation approach for meso-scale concrete samples with randomly generated and packed aggregates and pores. A simple algorithm is devised to discretize samples into meshes consisting of semi-analytical scaled boundary finite element (SBFE) polygons only. As each aggregate is modelled by one SBFE polygon and only polygonal boundaries are discretized into nodes, the degrees of freedom of a model is significantly reduced compared with conventional finite element models. The volumetrically averaged stress inside a SBFE polygon is semi-analytically integrated, leading to high accuracy in the homogenised elastic properties. The effects of model size and porosity are statistically studied by extensive Monte Carlo simulations. A size effect law taking porosity into account is proposed to predict effective elastic moduli in good agreement with experimental data up to 200 mm model size. The meso-models are found statistically homogeneous when the size is about 4.5 times the maximum aggregate size.