High-performance concrete produced with locally available materials
Vietnam is one of the countries most severely affected by climate change and sea level rise, especially in the south. High-performance concrete appears to be a better choice for strong and durable structures. The primary objective of this research was to use locally available materials to produce HPC reaching compression strength of over 100 MPa and suitable for Vietnamese climatic conditions and environment. The materials locally available in Vietnam used in the study included: sulfate-resisting Portland cement (PCSR40), crushed granite as coarse aggregate (size 9.5÷19 mm), river sand with fineness modulus of 3.0, Sika®Viscocrete®-151 type superplasticizer, mineral materials (class F fly ash and silica fume), and potable water. All concrete mixtures were designed according to TCVN 10306-2014 standard. For compressive strength, concrete samples were tested after 3, 7, 28, 56, and 450 days, while the tests for splitting tensile and flexural strengths, water absorption and permeability were conducted after 28 days. In this experimental research, the greatest compressive strength values obtained at 450 days of age were 95.426 MPa in a mix containing 10 %SF + 20 %FA + 20 %Qp and 101.597 MPa in a mix containing 12.5 %SF + 20 %FA + 20 %Qp. The results showed that the optimum high-performance concrete mixes used for construction in aggressive corrosive environment of Southern Vietnam contain 7.5 %SF + 30 %FA, 10 %SF + 20 %FA, 10 %SF + 30 %FA, 12.5 %SF + 20 %FA, respectively. This study showed that the HPC produced with locally available materials in Vietnam can have compressive strength exceeding 110 MPa as well as other excellent mechanical properties. All of this can be achieved simply by using materials available at the local markets, provided they are carefully selected and properly mixed to optimize grain size distribution.