This research is conducted with a view to investigate performance of concrete containing high volumes of ASTM Class C fly ash. A portland cement concrete, proportioned to have 28-day compressive strength of 6,000 psi (41 N4Pa) is used in this study. Concrete mixes are also proportioned to have various levels of cement replacement by fly ash ranging from 40% to 70% by weight. Concrete performanc...

this paper aims at investigating the influence of partial replacement of portland cement with ultrafine fillers compared to limestone powder on the durability and mechanical characteristics of concrete. for this purpose, ultrafine calcium carbonate materials with different specific surface areas of 9.7 and 15.1 m2/g and limestone powder (0.72 m2/g) were used. the results indicate that the ultra...

Pervious concrete is a green alternative to conventional pavements with minimal fine aggregate and a high void content. Pervious concrete allows water to infiltrate through the pavement, thereby reducing the runoff and the requirement for stormwater management systems. Seashell By-Products (SBP) are produced in an important quantity in France and are considered as waste. This work investigated ...

Aquaculture is among the oldest occupations of human being. Over the past quarter of century, the aquaculture industry has grown rapidly. The effect of water containing sodium sulfate on long term compressive strength of concrete of fishing ponds and channels is investigated in this paper. Aim of this paper was to analyze the strength of concrete channels and of aquaculture which are in direct ...

Aquaculture is among the oldest occupations of human being. Over the past quarter of century, the aquaculture industry has grown rapidly. The effect of water containing sodium sulfate on long term compressive strength of concrete of fishing ponds and channels is investigated in this paper. Aim of this paper was to analyze the strength of concrete channels and of aquaculture which are in direct ...

this paper describes the effects of reinforcement by randomly distributed nylon fibers and addition of nanoclay on some engineering properties of a typical asphalt concrete. the properties of asphalt concrete reinforced by different percentages of 25 mm nylon fibers have been compared with those of the mixtures containing different percentages of nanoclay and those in which both the fibers and ...

the performance of asphaltic pavements during their service life is highly dependent on the mechanical properties of the asphaltic layers. therefore, in order to extend their service life, scientists and engineers are constantly trying to improve the mechanical properties of the asphaltic mixtures. one common method of improving the performance of asphaltic mixtures is using different types of ...

Waters’ variant of the Boneh-Boyen IBE scheme is attractive because of its efficency, applications, and security attributes, but suffers from a relatively complex proof with poor concrete security. This is due in part to the proof’s “artificial abort” step, which has then been inherited by numerous derivative works. It has often been asked whether this step is necessary. We show that it is not,...