This paper reports the results of a study conducted to determine influence coarse aggregate type on workability, compressive strength, and flexural strength normal high concretes with target 28-day strengths 30 60 MPa two water/cement ratios 0.44 0.27. The were prepared using four types natural aggregates, namely diabase, calcareous, river gravel, basalt, maximum particle sizes 12.7 19.1 millim...

This paper presents a physical characterization for the recycling into new concretes of three comminuted concretes: C16/20 (“ordinary concrete”), C50/60 (“high strength and C70/85 (“very high concrete”). The top size crushed was 19.1 mm range 4.75 to mm. carried out with coarse aggregate liberation, be prepared concentrated in gravity concentration process. density distribution aggregate, cemen...

This paper presents the results of comprehensive laboratory work conducted for investigating mechanical and radiation attenuation characteristics heavyweight concrete produced with pyrite, chromium, magnetite aggregates normal weight concretes three different water/ cement (w/c) ratios. Various experiments were to determine compressive strengths, ultrasound transmission velocities, experimental...

This study compares the environmental impacts of blast furnace slag-, fly ash-, and metakaolin-based alkali-activated concretes with Portland cement (PC) using life cycle assessment methodology. The variability in production processes mix constituents across Europe uncertainty associated transportation distances are evaluated for both types concrete. recent data on soluble sodium silicates was ...

Abstract The article presents data on the deformation of elastic aftereffect concretes various compositions, at different stress levels prolonged loading, effect loading strength and diagram concrete work. Development relative creep deformations steamed concrete. development aftereffects natural hardening B series under stress. Data studied concretes. e_p(t) including after unloading samples.

cracked and un-cracked brazilian disc specimens subjected to diametral compression were used for conducting fracture toughness and tensile strength experiments on a polymer concrete (pc) material. the value of mode i fracture toughness (kic) was determined from the center- cracked brazilian disc and the indirect tensile strength (σt) was obtained from the un-cracked brazilian disc specimen. the...

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This paper discusses the reconstruction of three-dimensional material structures of pervious concretes using two-dimensional digital images obtained from actual specimens, and computational permeability predictions using these reconstructed three-dimensional material structures. The computer programs developed at the National Institutes of Standards and Technology (NIST) are used to obtain thre...