With careful design, mixed microstructures consisting of fine plates of upper bainitic ferrite separated by thin films of stable retained austenite have exhibited impressive combinations of strength and toughness in highsilicon bainitic steels. The silicon suppresses the precipitation of brittle cementite leading to an improvement in toughness. The essential principles governing the optimisatio...

recent tendencies in concrete technology have been towards to high- performance concrete with a low water-cement ratio. however, high performance concretes have some problems. one of the problems is early-age cracking due to autogenous shrinkage. this study presents the results of an experimental investigation carried out to evaluate the autogenous shrinkage of high-strength concrete. accordin...

with careful design, mixed microstructures consisting of fine plates of upper bainitic ferrite separated by thinfilms of stable retained austenite have exhibited impressive combinations of strength and toughness in highsiliconbainitic steels. the silicon suppresses the precipitation of brittle cementite leading to an improvement intoughness. the essential principles governing the optimisation o...

in this paper, the effect on the strength properties of high strength concrete (hsc) manufactured with silica fume (sf) and ground pumice (gp) is investigated. portland cement was replaced with sf, gp and combination of sf and gp up to 25%. 22 different concrete mixtures with these replacement ratios were produced by using 0.25 water-binder ratio. the ultrasound pulse velocity, compressive, spl...

in this paper, the effect of polypropylene fibers added to concrete on strength and thermal resistance of high strength concrete has been investigated. therefore, five tests have been carried out to reach this goal which it includes; effect of weight percent of polypropylene fibers on mechanical properties of concrete, effect of fiber’s length on the strength of high strength concrete, effect o...

stress-corrosion cracking (scc) tests were conducted in the near-neutral ph standard solution, ns4, and in an actual soil solution, using four-point bending at a high stress ratio and low frequency conditions very similar to those of operational pipelines. pitting incubation appeared first and then pitting initiated and grew in both solutions although there were many more pits on the specimen t...

in this study, in order to investigate the effect of increasing the manganese content on microstructure and mechanical properties of high manganese austenitic steels, three alloys with successive increases in weight percentages of manganese (7.55, 13.1, and 16.5) and carbon (0.8 and 1.2) were cast in the presence of a constant amount of chromium (1.5 wt.%) and silica (0.6 wt.%). the samples exp...

This paper presents a study about the bond of high strength concrete with high strength steel. Fourteen pull out tests were carried out to determine the bond. The concrete strength was about 70 MPa and the steel was a 500 MPa grade. Bar diameters used were 12, 16, 20, 25, 28, 32 and 36 mm. In order to investigate the effect of cover, each test was done twice, once in a 240 mm diameter concrete ...