Test To Check Initial And Final Setting Time Of Cement
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INITIAL AND FINAL SETTING TIME
We need to calculate the initial and final setting time as per IS: 4031 (Part 5) – 1988. To do so we need Vicat apparatus conforming to IS: 5513 – 1976, Balance, whose permissible variation at a load of 1000g should be +1.0g, Gauging trowel conforming to IS: 10086 – 1982.
Procedure to determine initial and final setting time of cement
i) Prepare a cement paste by gauging the cement with 0.85 times the water required to give a paste of standard consistency.
ii) Start a stop-watch, the moment water is added to the cement.
iii) Fill the Vicat mould completely with the cement paste gauged as above, the mould resting on a non-porous plate and smooth off the surface of the paste making it level with the top of the mould. The cement block thus prepared in the mould is the test block.
A) INITIAL SETTING TIME
Place the test block under the rod bearing the needle. Lower the needle gently in order to make contact with the surface of the cement paste and release quickly, allowing it to penetrate the test block. Repeat the procedure till the needle fails to pierce the test block to a point 5.0 ± 0.5mm measured from the bottom of the mould.The time period elapsing between the time, water is added to the cement and the time, the needle fails to pierce the test block by 5.0 ± 0.5mm measured from the bottom of the mould, is the initial setting time.
B) FINAL SETTING TIME
Replace the above needle by the one with an annular attachment. The cement should be considered as finally set when, upon applying the needle gently to the surface of the test block, the needle makes an impression therein, while the attachment fails to do so. The period elapsing between the time, water is added to the cement and the time, the needle makes an impression on the surface of the test block, while the attachment fails to do so, is the final setting time.
sir
i m student of structure. this material is too much helpfull to me specially in the course of concrete technology,
plz explain for me that what is air set in cement and what are their disadvantages
i want to know that what is the effect on setting of cement if we add fly ass in concrete
A INITIAL SETTING TIME OF 2 HR IS IT OK. AND FINAL SETTING TIME OF 3HRS.
dear Bolaji;
This depend on the properties of the cement under subject. OPC of 45 min as minimum and max of 10 hours of final could be acceptable.
initial setting time should not more than 30-40 min for ordinary portland cement,and final setting time is aprox 600 min
i would really like to know in details the importance of carrying out the tests for consistency of cement,initial and final setting time of ordinary portland cement(o.d.c.) before using the cement.if the cement does not meet up with standard by a small margin,can the cement be used for any other purpose,specify if so.
Daer Sir;
I think you need to confirm IS requirements with EN 196-3 as the initial setting penetration is somewhat little different from what you published.
Thanks
Dear Sir,
What is the relation between setting time and grade of cement?. How the setting time varies with different grade of cement?
Thanks in advance.