Assessing creep and creep recovery performance of plastic processed aggregate based concrete

The use of plastic in concrete through various substitution approaches have been targeted in last few decades with the main aim of plummeting the environmental loads of construction industry. Although the major mechanical and durability properties of plastic aggregate concrete have been studied in depth, petite data is available for its creep characteristics. Therefore, the current study was designed to access the creep and creep recovery of plastic processed aggregates concretes. Five concrete mixes consisting of plastic processed aggregate at replacement levels of 0%, 25%, 50%, 75% and 100% were developed at w/c of 0.5. The tests were conducted on all the specimens to determine the mechanical properties and evaluate the creep and creep recovery of the concrete for a period of approx. three years. The augmentation of plastic processed aggregate substitution resulted in the amplification of the instantaneous creep strain, ultimate shrinkage strain and ultimate creep strain of the plastic processed aggregate concrete. An increase of 100, 119 and 69% was noted for instantaneous creep strain, ultimate shrinkage strain and ultimate creep strain at total substitution. The creep recovery increased by 30.1, and 96.8% for a plastic processed aggregate replacement of 25% and 100% respectively. Overall it was noticed that the increase in the plastic processed aggregates have resulted in the decrease of compressive strength and increase of creep strains and creep recovery as compared to the reference mix. The results from this experimental study advocate the use of 100% plastic processed aggregates specifically for non-structural application requiring flexible solution.