Vee-Bee Test to Determine Workability of Concrete utilizing Consistometer

Target and Theory of Vee-Bee Test on Concrete:


The fundamental goal of Vee-Bee test is to decide the workability of the crisply blended cement. The Vee-Bee test gives a sign about the portability and the compactibility part of the naturally blended cement.

Vee-bee test does the relative exertion estimation to change the mass of the solid from a clear shape to the next. That is, according to the test, from the funnel shaped shape to the tube shaped shape by experiencing vibration process.

The estimation of the exertion is finished by time estimation in seconds. The measure of work estimated in seconds is called as the remolding exertion. The time required for the entire remolding is a measure of the workability and is communicated in the Vee-Bee seconds.

The trial is named after the designer V Bahrmer of Sweden. The technique can be additionally connected for dry cement. For solid that have slump value more than 50mm, the remolding action will be fast to the point that the estimation of time isn't conceivable.


Mechanical assembly for Vee-Bee test


The Vee-Bee test mechanical assembly comprise of a Vee-Bee consistometer according to Seems to be: 119 – 1959.The mechanical assembly comprises of a vibrating table

which is upheld and mounted on flexible backings. It additionally comprises of a sheet metal droop cone, a measuring balance, tube shaped compartment, a standard iron packing bar and trowels.

The vibrating table as appeared in figure-1 has a measurement of 380mm length and a width of 260mm. At a stature of 305mm, it is upheld on an elastic stun safeguard over the level of floor.

A vibrator is given under the table. This vibrator is worked electrically. The entire said get together is mounted on a base as appeared above which is in turn laying on elastic backings three in number.

The sheet metal droop cone shape has opening at the two closures and is put in a round and hollow compartment as appeared in figure-1. The barrel holder is mounted over the vibration table with the assistance of wing nuts.

The cone utilized as a part of the plan have stature equivalent to 300mm, the best and the base measurements as 200 and 100mm individually. Base comprise of a swivel arm holder. There is another swivel arm that is settled into it that comprise of a pipe and a guide sleeve.

The separation from the vibrating table is feasible for the swivel arm. A graduated bar is settled to the swivel arm through the guide sleeve. The graduated bar has the arrangement for screwing the straightforward plate.

The slump of the solid cone is estimated through the divisions on the scale set apart on the pole. A 20mm breadth standard iron packing bar is utilized that have a length of 500mm.

Technique of Vee-Bee Test on Concrete 

The technique for leading the Vee-Bee test are as per the following:

Stage 1:

At first the sheet metal droop cone is set inside the barrel holder that is put in the consistometer. The cone is loaded with four layers of cement.

Each solid layer is one fourth the stature of the cone. Each layer subsequent to pouring is subjected to twenty-five packing with the standard packing bar. The packing is finished with the adjusted end of the bar.

The strokes are conveyed in uniform way. This must be done in such a way theta the strokes led for the second and the consequent layers of concrete must enter the base layers.

Once the last layer has been set and compacted, the solid is struck off to make it in level with the assistance of a trowel. This makes the cone to be precisely filled.

Stage 2:

After the arrangement of the solid cone, the glass plate appended to the swivel arm is moved and is put on the highest point of the droop cone put inside the barrel shaped holder. The glass circle must be set with the end goal that it touches the highest point of the solid level and the perusing is estimated from the graduated pole.

Stage 3:

Presently the barrel shaped cone is evacuated quickly by bringing the cone gradually up in the vertical bearing. The straightforward circle on the highest point of the solid is set down to the new position and the perusing is resolved.

Stage 4:

The distinction in the qualities estimated from stage 3 and stage 4 will give the droop.

Stage 5:

Presently the electrical vibrator is exchanged on and in the meantime we need to begin the stop watch. The solid is permitted to spread out in the tube shaped compartment.

Until the point when the solid is remolded the vibration is proceeded. This stage is the point at which the surface of the solid ends up plainly flat and the solid surface totally clings consistently to the straightforward circle.

Stage 6:

The time required for finish remolding in seconds is recorded. This time in seconds gives us the measure of workability of the crisp cement. This time is communicated in Vee-Bee seconds.

Perception and Calculations in Vee-Bee Test 

Beginning perusing from the graduated bar, before unmolding (an) in mm

The last perusing on the graduated pole subsequent to evacuating the form (b) in mm

Slump = a – b in mm

The time required for finish remolding in seconds

Henceforth the consistency of the solid is estimated in — - vee-bee seconds.

Safety measures Necessary in Vee-Bee Test 

The form ought to be cleaned and free from dampness inside before including the solid blend.

While the strokes are connected over the layers, mind must be taken to apply it consistently all through the layers. This aides in having the effect of the strokes in full profundity.

The expulsion of the droop cone ought to be lifted upward such that the solid cone isn't aggravated in any methods.

The vee-honey bee tests must be led at a separation far from some other wellspring of vibration than the vibration system gave in the test.

At the point when a state achieves at which the straightforward circle rider totally covers the solid and every one of the voids and holes displays in the solid surface get vanished, the remolding of cement is accomplished totally.

Vee-Bee Test Compared with Other Workability Tests 

The test system of Vee-Bee test does the comparative methodology that a newly blended cement is subjected to in its genuine state. This is an additional favorable position of Vee honey bee test when contrasted and different tests, the slump test and the compaction factor test.

The remolding fruition is outwardly learned that can cause trouble in estimating the end-point and henceforth have the odds to have mistakes. This possibility of mistake is more articulated in the solid blends that have higher workability. This blend hence has a lower an incentive for Vee-Bee time.

In the instances of cement blends that have droop esteem more noteworthy than 125mm, the wonder of remolding is observed to be fast and the time can't be estimated. This implies the Vee honey bee test isn't reasonable for estimating the portability of cement of higher workability. This higher workability comes in the scope of droop esteem more prominent than 75mm.

In a few circumstances, this issue is overwhelmed by making utilization of a programmed working gadget that records the development time. By and large, the Vee-honey bee test is ideal suited for concrete blends that have low or low estimation of workability.

Among the three-workability test suggested by IS: 119 - 1959 i.e. the droop test, the compaction factor test, and the Vee-honey bee test, the droop test strategy is most mainstream test to quantify solid workability.

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