Fracture behaviours of sustainable multi-recycled aggregate concrete under combined compression-shear loading
Research output: Contribution to journal › Research article › Contributed › peer-review
Contributors
Abstract
Multi-recycling of concrete waste presents a promising alternative for reutilization of construction and demolition wastes. This study aims to investigate the synthetic effects of normal stress ratio (σ/fc) and number of recycling cycles (n) on mechanical performance and damage evolution of 3 generations of multi-recycled aggregate concrete (Multi-RAC) under combined compression-shear loading. Both the σ/fc and n significantly affect the failure mode, mechanical strength, stress-displacement relation, and damage evolution characteristics of Multi-RAC. The shear strength increases with the increased σ/fc, but decreases with the increased n except for σ/fc= 0. When σ/fc increases from 0 to 0.8, the failure modes shift from typical shear failure mode to complex failure one with combined shear and axial collapse features. The incemental reductions of contact friction strength and aggregate interlock strength are the main contributors to the decrease of shear strength with increased n. However, with increased σ/fc, the contributor fraction of contact friction strength contributing to the degradation of shear strength is decreased, whereas the corresponding contributor fraction of aggregate interlock strength is increased. The proposed aggregate interlock model of multiple recycled coarse aggregate (Multi-RCA) unveils the mechanism for the incremental reduction of aggregate interlock strength with the increasing n. The distinctively reduced volume fraction of natural coarse aggregate (NCA) in Multi-RCA mainly contributes to the reduced aggregate interlock strength. The findings provide an insight into the mechanical behaviors and damage evolution of Multi-RAC and can promote its application as structural concrete.
Details
Original language | English |
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Article number | 106382 |
Journal | Journal of Building Engineering |
Volume | 72 |
Publication status | Published - 1 Aug 2023 |
Peer-reviewed | Yes |
Keywords
ASJC Scopus subject areas
Keywords
- Compression-shear loading, Damage evolution, Mechanical properties, Multi-recycled aggregate concrete, Strength criterion