write a conclusion for Test Methods for Time of Setting of H

write a conclusion for Test Methods for Time of Setting of Hydraulic Cement by Vicat Needle experiment describing results of this experiment and the expected ideal result of this experiment. Then compare them with recommendation and conclusion.

Solution

Standard consistency of a cement paste is defined as that consistency which will permit a vicat plunger having 10 mm dia and 50 mm length to penetrate to a depth of 33-35 mm from top of the mould.

This test method is used to determine the time of setting of the hydraulic cement by VICAT needle apparatus.

We always prefer a larger initial setting time so that we can mix, transport and place the concrete easily. According to ASTM specifications, the initial setting time shall not be less than 45 min but in the field we prefer an initial setting time not less than 90 min.

A smaller value of the final setting time is always preferred in order to avoid large expenditures on the formwork. According to most of the specifications, the final setting time shall not be greater than 10hrs and shall not be less than ( 90 + 1.2 x (initial setting time) ) min.

i.e. ( 90 + 1.2 x (initial setting time) ) min < final setting time < 10hrs.

COMPARISION

NAME OF TEST AMOUNT OF WATER REQUIRED

Soundness (Le-chatelier method) 0.78 P (P=Consistency of standard cement paste)

Setting time 0.85 P (P=Consistency of standard cement paste)

Compressive strength cement consistency 2of combined mass of cement and sand.