Lowering paste volume of SCC through aggregate proportioning to reduce carbon footprint

A New Approach for Designing Fluid Concrete with Low Cement Content: Optimization of Packing Density of Aggregates

“…Moreover, as the cementitious powders are the most expensive component among the SCC raw materials, the application of SCC also limited due to its high cost per unit volume [14]. In recent years, many studies have focused on reducing the amount of cementitious materials used in fluid concrete [13,[15][16][17][18][19]. Three methods can be commonly used to reduce the cementitious binder content.…”

“…In recent years, many studies have focused on reducing the amount of cementitious materials used in fluid concrete [ 13 , 15 , 16 , 17 , 18 , 19 ]. Three methods can be commonly used to reduce the cementitious binder content.…”

“…First, the replacement of the cement clinker by grounded stone powders while maintain the same workability and mechanical performances [ 17 , 20 ]. Secondly, the optimization of aggregate packing density to achieve the required workability while using less interstitial paste as the lubricant phase [ 13 , 15 , 18 ]. Thirdly, a high water to powder ratio can be adopted for the structures that require low mechanical strength grade [ 13 , 14 ].…”

Packing and film thickness theories for the mix design of high-performance concrete

“…Nevertheless, the authors have observed that when a concrete mix exhibited sign of segregation, the fine aggregate particles finer than 1.2 mm tended to be staying with the paste. In view of this observation, it has been postulated that the fine aggregate particles <1.2 mm would behave in a different manner from the larger size particles, such that the coherent mixture of paste and fine aggregate particles <1.2 mm would have greater influence on the rheological properties of concrete compared to the mixture of paste and fine aggregate with 5.0 mm maximum size Kwan and Ling, 2015). Herein, the authors suggest to redefine the mortar portion of concrete as the mixture of paste and fine aggregate particles finer than 1.2 mm (it is in fact usual to use mortar mixes containing fine aggregates of maximum size up to 1.2 mm for screeding, rendering and blockwork applications).…”

“…After mixing, fresh concrete was sampled from the batch for undergoing the slump flow test, V-funnel test, sieve segregation test, and U-box test. These tests had been employed to testify the desirable rheology of self-consolidating concrete mixes by the authors' research team (Ng et al, 2006;Kwan and Ng, 2008;Kwan and Ling, 2015;Ling and Kwan, 2015). The tests were conducted within 30 min, during which the changes in rheological properties should be insignificant.…”