Bissoy.com
Doctors Medicines MCQs Q&A

Consider the following statements regarding the 'strength of cement': 1. Strength test on cement is made on cubes of the cement-sand mix. 2. Water to be used for the paste is 0.2P, where P is the water needed for normal consistency. 3. The normal consistency is determined on Le Chatelier's apparatus. 4. Cubes are cast in three layers in leak-proof moulds further compacted in each layer by vibration on a machine. Which of the above statements are correct?

Consider the following statements regarding the 'strength of cement': 1. Strength test on cement is made on cubes of the cement-sand mix. 2. Water to be used for the paste is 0.2P, where P is the water needed for normal consistency. 3. The normal consistency is determined on Le Chatelier's apparatus. 4. Cubes are cast in three layers in leak-proof moulds further compacted in each layer by vibration on a machine. Which of the above statements are correct? Correct Answer 1 and 4

Concept:

Compressive strength: this test is carried out to determine the compressive strength of cement. Following procedure is adopted:

The mortar of cement and sand is prepared. The proportion is 1 : 3 which means that x gm of cement is mixed with 3 x gm of sand.

The water is added to the mortar. The water cement ratio is kept as 0.4 which means that x gm of water is added to dry mortar.

Water to be used for the paste is (P/4) +3%, where P is the water needed for normal consistency.

The mortar is placed in moulds in three layers. The test specimens are in the form of cubes with side as 70.6 mm or 76 mm. the moulds are of metal and they are constructed in such way that the specimens can be easily taken out without being damaged for 70.6 mm and 76 mm cubes, the cement required is 185 gm and 235 gm respectively.

The mortar, after being placed in the moulds, is compacted in vibrating machine for 2 minutes.

The moulds are placed in a damp cabin for 24 hours.

The specimens are removed from the moulds and they are submerged in clean water for curing.

The cubes are then tested in compression testing machine at the end of 3 days and 7 days. The testing of cubes is carried out on their three sides without packing. Thus three cubes are tested each time of find out the compressive strength at the end of days and 7 days. The average value is then worked out. During the test the load is to be applied uniformly at the rate of 350 kg/cm2 or 35 N/mm2.

The compressive strength at the end of 3 days should not be less than 115 kg/cm2 or 11.50 N/mm2 and that at the end of 7 days should not be less than 175 kg/cm2 or 17.50 N/mm2.

Le Chatelier's apparatus is used to determine the unsoundness due to lime.

Here statement 1&4 are correct.

Other Important Points:

Autoclave test is used to determine unsoundness due to magnesia.

Vicat apparatus is used to determine the consistency of cement.

Le Chatelier's flask is used to determine the specific gravity of cement.

Sieve test and Blainis air permeability apparatus is used to determine the fineness of the cement.

Related Questions

Some small cubes of same height 7 cm but variable length and width are put inside a large cuboid of height 21 cm. Length and width of cuboid is 32 cm and 24 cm, respectively. Small cubes are put such that cubes at the bottom most layer is of similar base area; second layer contains all the cubes of similar base area and third layer have all the cubes of similar base area. Which of the following statement(s) given below is / are TRUE? A: If side of each small cubes at bottom most layer is 8 cm, then maximum number of small cubes that can be put at bottom most layer is 12. B: If maximum of 48 cubes can be put at second layer, then side of each cube at second layer is 6 cm. C: If side of each small cubes at third layer is 1.6 cm, then maximum number of small cubes that can be put at third layer is 300.
In conducting a standard consistency test of Ordinary Portland cement using Vicat apparatus as per IS 4031-1988, what is the penetration depth of the needle from the top of Vicat mould, for the paste to have normal consistency?
Which of the following are the basic differences between vibration signature and noise signature? 1. Vibration signature is essentially in the frequency range zero to 100 cps whereas noise signature is in the range 20 cps to 3000 cps. 2. Vibration signature has well-defined peaks whereas the noise signal is smeared. 3. The intensities of noise signatures arc much less than that of vibration signatures. 4. Detection of vibration signature calls for a microphone whereas that of noise can do with a pickup. Select the correct answer using the code given below.
Consider the following statements : (1) Tests on cement paste to determine initial and final setting times are done at 0.85 times normal consistency conditions. (2) Low heat cement has a high percentage of tri-calcium aluminate. (3) High early strength Portland cement contains a large percentage of tricalcium silicate and lower percentage of dicalcium silicate. Which of these statements are correct ?
The following are the conditions for selecting list of a suitable candidates to be called for interview after the written test for the recruitment is conducted/organized for management - level persons for a multi - national company. For providing accounting services and sales the candidate must (a) be holding a graduation in basic science with 65% or above or B.E. degree with 55% and above marks (b) have passed the written test with 70% or above marks (c) the age must be in the group 25 to 30 years as on 1/4/18 (d) have experience in an accounting firms for three years and diploma in accounting with 60% or above marks (e)  be presently drawing CTC of 6 Lakhs per annum and above In case the applicant who satisfies all other terms above except 1) at (a) above, then be referred as Junior Accountant 2) at (d) & (e) above then be referred as Trainee - Accountant Satisfying all the above with experience of 5 years then the referred as senior-Accountant Satisfying all the above criteria (a - e) with CA/ICWA/MBA (Finance) then be referred as manager (Accounts) Read all the above information and answer the following question Praveen has done his Masters in physics. He has no experience in accounting neither diploma. He is ready to be on training for accounting after joining. For which position he may be referred
The following are the conditions for selecting a list of suitable candidates to be called for interview after the written test for the recruitment is conducted/ organized for management-level persons for a multi-national company. For providing accounting services and sales the candidate must (a) beholding graduation in basic science with 65% or above or B.E. degree with 55% and above marks (b) have passed the written test with 70% or above marks (c) the age must be in the group 25 to 30 years as on 1/4/18 (d) have experience in an accounting firm for three years and a diploma in accounting with 60% or above marks e) be presently drawing CTC 6 lakhs per annum and above In case the applicant who satisfies all other terms above except 1) at (a) above, then be referred to as Junior Accountant 2) at (d) & (e) above then be referred to as Trainee-Accountant Satisfying all the above with experience of 5 years then be referred to as senior-Accountant Satisfying all the above criteria (a-e) with CA/ICWA/MBA (Finance) then be referred to as manager (Accounts) Read all the above information and answer the following question   Praveen has done his Masters in physics. He has no experience in accounting neither diploma. He is ready to be on training for accounting after joining. For which position he may be referred.
The following are the conditions for selecting list of a suitable candidates to be called for interview after the written test for the recruitment is conducted/ organized for management-level persons of a multi-national company. For providing accounting services and sales the candidates must (a) be holding a graduation in basic science with 65% or above or B. E degree with 55% and above marks (b) have passed the written test with 70% or above marks (c) the age must be in the group 25 to 30 years as on 1/4/18 (d) have experience in an accounting firms for three years and diploma in accounting with 60% or above marks (e) be presently drawing CTC of 6 Lakhs per annum and above In case the applicant who satisfies all other terms above except 1) at (a) above, then be referred as Junior Accountant 2) at (d) & (e) above then be referred as Trainee-Accountant Satisfying all the above with experience of 5 years then be referred as senior-Accountant Satisfying all the above criteria (a-e) with CA/ ICWA / MBA (Finance) then be refereed as manager (Accounts) Read all the above information and answer the following question Shravani has passed H. SC with 72% of marks. She has done diploma in accountancy with 62% of marks. She was working with an organization in the field of accounting in the field of accounting from 4 years and was drawing CTC of 6.5 Lakhs presently. She is 28yrs as on July 2018. She may referred for the position of:
The following are the conditions for selecting list of a suitable candidates to be called for interview after the written test for the recruitment is conducted/ organized for management-level persons of a multi-national company. For providing accounting services and sales the candidate must (a) be holding a graduation in basic science with 65% or above or B.E degree with 55% and above marks (b) have passed the written test with 70% or above marks (c) the age must be in the group 25 to 30 yrs as on 1/4/18 (d) have experience in an accounting firms for three yrs and diploma in accounting with 60% or above marks (e) be presently drawing CTC of 6 Lakhs per annum and above In case the applicant who satisfies all other terms above except 1) at (a) above, then be referred as Junior Accountant 2) at (d) & (e) above then be referred as Trainee-Accountant Satisfying all the above with experience of 5 yrs then be referred as senior-Accountant Satisfying all the above criteria (a-e) with CA/ ICWA/ MBA (Finance) then be refereed as manager (Accounts) Read all the above information and answer the following question: Radha Mohan has done her graduation in physics with 58% of marks. She has passed the written examination with 76% of marks. She is 27 yrs as on June 2018. She has the experience in the accounting company for four years with salary of 7 Lakhs per annum. She also has passed diploma in accounting with 61% of marks. She may be referred for the position of:
Which of the following statements are correct with reference to ensuring minimum shrinkage of prestressed concrete? 1. The water-cement ratio and proportion of cement paste should be kept minimum to reduce shrinkage. 2. Aggregates of larger size, well graded for minimum void, need a smaller amount of cement paste, and attendant shrinkage will be smaller. 3. Harder and denser aggregates of low water absorptions and high modulus of elasticity will exhibit small shrinkage.
Consider the following forms of water in a hydrated cement paste: 1. Capillary water 2. Chemically combined water 3. Interlayer water 4. Adsorbed water Which of the above forms of water will on its/their removal, cause shrinkage of the paste?