The construction industry consumes enormous quantities of concrete, which subsequently produces large amount of material waste during production and demolishing. As a result, the colossal quantity of concrete rubble is disposed in landfills. This paper, therefore, evaluated the feasibility of reusing waste concrete as recycled aggregate (RA) to produce concrete. The replacement levels were 20, 50, and 80% RA of normal coarse aggregate. Micro silica (MS) and fly ash (FA) were used as cementitious replacement material, however, the water-to-binder ratio (w/b) was kept constant at 0.31. A total of 44 specimens were used to evaluate the fresh and hardened properties. Concrete with 80% RA showed good workability and mechanical properties. The compressive strength of the concrete with 80% RA was 60 MPa at 28 days and 77 MPa at 56 days. Rapid chloride penetration test (RCPT) was also conducted, where the concrete with 80% RA had the lowest permeability.

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The mechanical behaviour of metamaterials typically depends on their microstructural configuration and composition, in addition to their relative density. The design of these materials requires extensive experiments or complex finite element models which tend to be numerically demanding. In order to understand, control and optimise the macroscopic mechanical behaviour, in this paper numerical homogenisation is applied to a simple square unit cell with a single inclusion using a combination of elastic and viscoelastic responses on the micro level. Through a systematic analysis of unit cell behaviour with increasingly complex microstructural configurations, it is shown how certain macroscale constitutive laws can be obtained in a controlled and controllable manner.