Recycled aggregates from construction and demolition wastes as alternative filling materials for highway subgrades in China

Effects of Gravel Content and Shape on Shear Behaviour of Soil-Rock Mixture: Experiment and DEM Modelling

Effects of gravel content and shape on shear behaviour of soil-rock mixture: Experiment and DEM modelling

Characterising the resilient behaviour of pavement subgrade with construction and demolition waste under Freeze–Thaw cycles

Stress-dependent water retention of granite residual soil and its implications for ground settlement

Modeling humidity and stress-dependent subgrade soils in flexible pavements

The cumulative permanent strain of subgrade soils plays an important role in the pavement structure design and long-term pavement performance maintenance. In Southern China, the hot and humid clima...

Prediction of permanent deformation for subgrade soils under traffic loading in Southern China

Construction and demolition (C&D) materials obtained from the demolition of buildings are proven to be qualified and sustainable subgrade fillers. The permanent deformation response of subgrade C&D materials under different moisture contents, degrees of compaction, deviator stresses, and confining pressures was revealed by carrying out dynamic triaxial texts. Then, using a four-factor and three-level orthogonal test and by calculating the Gray correlation degree of each factor, the influence degree of each factor on the permanent deformation was determined. The results indicated that two different response types of the permanent deformation of subgrade C&D materials, plastic shakedown and plastic creep, were identified as reason behind the increase in stress levels. Also, according to the Gray correlation analysis results, the permanent deformation of highway subgrade filled with C&D materials is influenced by the deviator stress most significantly, followed by moisture content, degree of compaction, and confining pressure. Finally, a permanent deformation prediction model about this kind of subgrade filler with a reasonable prediction accuracy was proposed.

Gray Correlation Analysis and Prediction on Permanent Deformation of Subgrade Filled with Construction and Demolition Materials

The Monte Carlo simulation (MCS) has been developed to estimate the strength distributions of heterogeneous materials influenced by different factors. The method presents a statistical correlation between the macroscopic properties and the non-uniform characteristics at meso scale. This study proposes an extensive MCS to investigate the influence of the aggregate morphology on deformation behaviour of unbound granular materials (UGMs) based on a real aggregate library and the discrete element method. Two indexes, elongation index (EI) and flatness index (FI), were used to evaluate the morphological characteristics of 3D aggregates rebuilt by the X-ray CT technique. Furthermore, repeated load triaxial tests of UGMs were simulated by 50 MCS samples. The effects of shapes and sizes of aggregates on deformation behaviours were statistically analysed. The results show that the deformation behaviour is dependent on the size and the EI distribution, but insensitive to the loading frequencies and FI distribution. 

Anshun Zhang

Papers

Effects of Gravel Content and Shape on Shear Behaviour of Soil-Rock Mixture: Experiment and DEM Modelling

Modeling humidity and stress-dependent subgrade soils in flexible pavements

Prediction of permanent deformation for subgrade soils under traffic loading in Southern China

Gray Correlation Analysis and Prediction on Permanent Deformation of Subgrade Filled with Construction and Demolition Materials

Monte Carlo simulations of deformation behaviour of unbound granular materials based on a real aggregate library