Effect of the amount of river sediment on the basic properties of cement mortars

Abstract

According to current legal regulations, bottom sediment in watercourses containing heavy metals are considered dangerous to the environment and should be properly managed after extraction. Due to the well-known excellent ability of the products of cement hydration to immobilize heavy metals, the possibility of utilizing this type of waste products in cement composites was preliminary tested. For this purpose, basic research was carried out on the technological and mechanical characteristics of binders containing sediment from one of the rivers located in Lesser Poland. Standard mortars made of Portland cement CEM I and river sediment dried at 105°C were used for the tests. This supplement replaced cement in the amount of 10%, 20%, 30% and 40% by weight. The technological properties such as: water demand, setting time, consistency and mechanical properties were verified. Compressive and tensile strength at bending of hardened mortars were tested at different curing periods, i.e. after 14, 28 and 90 days. The obtained test results confirm that the fraction of river sediment in the binder in the amount of 10% generally does not adversely affect the properties of mortars, however, its greater amount is reflected in changes in the technological features and in a clear reduction of mechanical properties of the tested mortars.

Reuse of Lake Sediments in Sustainable Mortar

“…. ), so that sediment-based mortar obtained from these studies is not such a sustainable material [27][28][29][30][31][32][33]. In any case, treatments to which sediments are submitted successfully transform them into secondary raw materials suitable for reuse in the fabrication of a wide range of materials, such as ceramics, supplementary cementitious materials, fill materials, paving blocks, partition blocks, ready-mixed concrete, and foamed concrete [34].…”