Category: Concrete Workability

Since the early 20th century, the concrete industry has recognized the need to monitor concrete workability to ensure that concrete can be properly placed and can achieve adequate hardened strength. A myriad of test procedures for determining workability have been developed for research, mix proportioning, and field use. The vast majority of these test methods have never found any use beyond one or two initial studies. With the exception of the widely used slump test, the few methods that have been studied extensively have generally failed to gain widespread acceptance. Even with the increase in knowledge of concrete rheology, the slump test remains the predominately used test method for measuring concrete workability.

Category: Concrete Workability ViscoCorder

The ViscoCorder is a single-point device used in Germany to measure the consistency of fresh mortar. Banfill (1990) modified the test to measure both the yield stress and plastic viscosity of mortar. The device consists of a metal cylinder mounted on a rotating turntable. A paddle inserted in the cylinder is connected to a calibrated spring that measures the torque

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Category: Concrete Workability Vicat Needle Test

The setting time of concrete, mortar, or paste can be measured as an indication of workability (Ferraris 1999). One of the most common tests is the Vicat needle test for testing cement paste (ASTM C191). The Vicat needle test is also used in ASTM C953 for grout for pre-placed aggregate concrete. The Vicat needle apparatus consists of a 300 g

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Category: Concrete Workability Mini-Flow Test

The mini-flow test (Zhor and Bremner 1998) is a variation of the mini-slump test described in the above subsection. The plexiglass sheet used in the modified version of the mini-slump test is mounted to a standard flow table, as described in ASTM C230. After the mini-slump cone is lifted from the sample of cement paste, the table is dropped 15

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Category: Concrete Workability Mini-Slump Test

The mini-slump test, which was originally developed by Kantro (1980) and later modified by Zhor and Bremner (1998), measures the consistency of cement paste. The mini-slump cone is simply a small version of the slump cone. The mini-slump cone has a bottom diameter of 38 mm, a top diameter of 19 mm, and a height of 57 mm. The cone

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Category: Concrete Workability Turning Tube Viscometer

The turning tube viscometer (Hopkins and Cabrera 1985; Ferraris 1999) is based on the same principle as the moving sphere viscometer—namely, Stoke’s Law—but is only considered appropriate for testing mortar. An 800 mm long, 60 mm diameter tube is attached to a rotating arm, which allows the tube to be rotated in the vertical plane. A metal ball is allowed

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Category: Concrete Workability Wuerpel Device

The Wuerpel device (Maultzsch 1990) measures the consistency of mortars by applying a shear force to a mortar specimen and measuring deformation energy. The apparatus consists of a quadratic mold with side lengths of 100 mm and a height of 50 mm. The corners of the mold are hinged to allow the mold, which is filled with compacted mortar, to

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Category: Concrete Workability Flow Cone Test

Several versions of a funnel test are used to measure the workability of pastes and grouts. These devices differ in dimensions and intended uses; however, they all work on the principle of measuring the time for fresh paste or grout to flow through the opening of a funnel. The flow cone test (Scanlon 1994) is intended for use in measuring

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Category: Concrete Workability Penetration Test for Segregation

The penetration test for segregation (Bartos, Sonebi, and Tamimi 2002; Bui, Akkaya, and Shah 2002) measures the penetration resistance of highly fluid and self-compacting concretes. The test apparatus consists of a hollow cylindrical penetration head that is allowed to sink under its own weight into a sample of concrete. The penetration head has an inside diameter of 75 mm, a

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Category: Concrete Workability Wet Sieving Stability Test (GTM Screen Stability Test)

The wet sieving stability test (EFNARC 2002; Bartos, Sonebi, and Tamimi 2002) was developed by a French contractor to measure the segregation resistance of self-compacting concrete. To perform the test, a 10 liter sample of concrete is placed inside a bucket and allowed to sit for 15 minutes to allow any internal segregation to occur. The container is sealed to

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Category: Concrete Workability Fill Box Test (Simulated Filling Test, Filling Capacity Box, Kajima Test)

The fill box test (EFNARC 2002; Bartos, Sonebi, and Tamimi 2002) measures the passing ability and segregation resistance of self-compacting concrete. The apparatus consists of a clear plastic box with 35 plastic 20 mm diameter bars, as shown in Figure 28. An early version of the test featured a wedge shaped box instead of a rectangular box and did not include

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