Comparison of Slump Cone and V-B Tests as Measures of Workability for Fiber-Reinforced and Plain Concrete

Abstract

In this paper, two popular measures of workability, namely, slump and V-B time, are compared for plain and steel (hooked) fiber-reinforced concrete. The results are based on experiments made on both types of concrete with and without high-range, water-reducing admixture. The fibers were 50 mm (2 in.) long with deformed ends glued together side by side into bundles (collated) with a water-soluble glue. The W-C ratio varied from 0.3 to 0.62. The air content ranged from 2 to 12%. In terms of workability, the whole spectrum ranging from no slump concrete to flowing concrete was covered. Based on the results of this investigation, the following general equation can be written relating V-B time and slump log10(V∙B)=a−b(slump) The addition of high-range water reducer and fibers influences the relationship and hence the constants a and b. The slope of the line, b, is highest for plain concrete without high-range, water-reducing admixture and lowest for fiber-reinforced concrete. In the case of plain concrete, the addition of high-range water reducer seems to result in a more cohesive mixture. As a result, V-B times can be recorded for slumps as high as 163 mm (6.4 in.). Without the addition of the admixture, concrete seems to collapse around a slump of 89 mm (3.5 in.). The addition of fibers increases the cohesiveness of the mixture considerably. For fiber-reinforced concrete made using high-range water reducer, V-B time could be measured for slumps as high as 221 mm (8.7 in.). Generally for a given slump, fiber-reinforced concrete has a higher V-B time than plain concretes.

Evaluating the influence of fly ash and waste glass on the characteristics of coconut fibers reinforced concrete

“…The workability of different concrete blends was determined following ASTM C143. 75 To evaluate the mechanical performance of concrete, samples were prepared and cast that had a length of 12 inches and a diameter of 6 inches, as shown in Figure 4a. The concrete was filled in three layers, and every layer was compacted 25 times using a steel rod.…”

Review on characteristics of concrete reinforced with nylon fiber

“…38 Due to the relatively large surface area of fibers, water use has increased. [39][40][41][42][43] Concrete requires more energy to flow by its weight because the aggregate and fibers in the blends have higher friction with one another. 44 The results showed that the slump value declined as the quantity of waste rope fiber in the blend raised.…”