The influence of retained moisture in aggregates from recycling on the properties of new hardened concrete

In this study the influence of retained moisture in recycled aggregates on the mechanical properties and durability of new concrete is determined experimentally and analysed. The effects of three different moisture conditions from the recycled agreggate are compared (dry, saturated and semi-saturated). A slight decrease is to be observed in the compressive strength of the concrete made from dry and saturated recycled aggregates respectively. The decrease is especially noticeable in flexural strength in the concrete with the saturated aggregates. The bad resistance to freeze-thaw of concretes with saturated and dry recycled aggregates and the good results of those made with semi-saturated aggregates can be explained as being due to the different quality of the interfaces formed in each case.