Mechanical performances and durability analysis of sand concrete. Nano-silica

      Аннотация: This Book consists of the study of the evolution of the durability of sand concrete containing two mineral additions (crushed dune sand and nano-silica (NS)) in four storage media (free surface, plastic film, tap water and ground water).The potential negative effects of adding these alternative materials can be reduced by adding nanosilica to the cementitious system at very low quantities. This study evaluates the feasibility of using these alternative materials and nano‑silica (NS) in producing lightweight aggregate concretes .The first step of our study is the characterization of the constituents used in the perfection of the sand concrete, then we study the effect of the additions of nano‑silica (NS)with a percentage of 2% and dune sand powder from the region of Ouargla (5%, 10%) and the combination between two additions (2%NS+5%SDP; 2% NS +10%SDP). Thus, tests of flexural and compressive strength at 7, 28, 90 and 120 days are carried out in order to estimate and evaluate the durability. The results obtained in this experimental study allow us to say that sand concrete with 5SDP 2 NS or 10SDP 2 NS has a stable compressive strength after 90 days in tap water and groundwater.

Ключевые слова: concret sand, nano silica