Early‐age behavior and mechanical properties of cement‐based materials with various types and fineness of recycled powder

Abstract

Recycled powder (RP) that includes recycled paste powder (RPP), recycled mortar powder (RMP), and recycled concrete powder (RCP) is an eco-friendly alternative binder. This work investigated the influence of RP types and fineness on early-age behavior and mechanical strength of cement-based materials. The results show that substituting RP for cement causes the reduction of new hydration products in cement-based materials. The blended RP decreases the fluidity of paste mixture, and the fluidity of paste including fine RPP is lower than that of paste including fine RMP and RCP; moreover, the fluidity increases following the growth of RP particle size. Incorporating fine RPP

Residual mechanical properties of concrete containing lightweight expanded clay aggregate (LECA) after exposure to elevated temperatures

“…Concrete has become the most widely used material in the construction industry throughout the world, mostly due to its economy, good mechanical properties and durability, especially when appropriately reinforced. [1][2][3][4][5] It is well known, however, that the permanent loads (mainly concrete self-weight) comprise a sizeable share of the loads applied to the structural components in reinforced concrete buildings. As a result, reducing the weight of the structural components (beams, columns, and especially floor slabs) using lightweight concrete (LWC) has been of interest to structural engineers.…”

“…Concrete has become the most widely used material in the construction industry throughout the world, mostly due to its economy, good mechanical properties and durability, especially when appropriately reinforced 1–5 . It is well known, however, that the permanent loads (mainly concrete self‐weight) comprise a sizeable share of the loads applied to the structural components in reinforced concrete buildings.…”