Which of the following are the disadvantages of no fine concrete?
The principal advantages claimed for no-fines concrete are economy in materials, somewhat higher thermal insulating values, lower shrinkage, and lower unit weight. The major disadvantages are its low compressive, flexural, and bond strength, and higher permeability.
Can you prepare concrete without using fine aggregates?
Back in India, a study carried out by the Central Road Research Institute (CRRI) has also shown that copper slag can be used as a partial replacement for sand as fine aggregate in concrete up to 40 per cent in pavement grade concrete without any loss of cohesiveness and the compressive and flexural strength of such …
What is no fines concrete and its intended purpose?
Nowadays, special concrete is widely adopted in construction industry. No-fines concrete is a one of the special concrete which eliminate the use of fine aggregates in concrete mixing. The application of no-fines concrete has been introduced to construction industry especially pavement construction.
Which of the following are the advantages of no fines concrete?
ADVANTAGES OF NO-FINES CONCRETE:
- The density of no fines concrete is very low.
- No fines concrete does not segregate and the capillary movement of water is almost nil.
- It has better thermal insulating characters due to the presence of large voids.
- This concrete can be used by dropping from a permissible height.
When should concrete be laid under water?
quick setting cement
When concrete is to be laid under water ___________ is to used. Explanation: When concrete is to be laid under water, quick setting cement is to used.
What is the permissible limits of suspended matter in water for construction?
Explanation: 2000mg/l is the standard value for the permissible limits for construction of suspended matter in water.
Can I mix cement with water only?
Cement mixed with water alone creates a grout which can be used for repairing any damage on concrete structures. This cement-based grout mix is also used in situations where normal concrete won’t work, such as underwater concreting. Concrete is used all over the world because it is durable, economical and versatile.
Does all concrete have rocks in it?
Concrete Basics In its simplest form, concrete is a mixture of paste and aggregates (sand & rock). The paste, composed of cement and water, coats the surface of the fine (sand) and coarse aggregates (rocks) and binds them together into a rock-like mass known as concrete.
Which of the workability test tests should be used for no fines concrete?
The workability results also are not satisfactory. No standard method is recommended, like slump test or compacting factor test for measuring the consistency of No-Fines concrete. Perhaps slump test is used along with the visual observation.
Which one of the following is a no fines concrete?
Concrete Technology Questions and Answers – No Fines Concrete, High Density Concrete. This set of Concrete Technology test focuses on “No Fines Concrete, High Density Concrete”. Explanation: No fines concrete is one type of light weight concrete.
What does adding water to concrete do?
Adding more water to the concrete increases workability but more water also increases the potential for segregation (settling of coarse aggregate particles), increased bleeding, drying shrinkage and cracking in addition to decreasing the strength and durability.
How you will conclude the consistency of cement?
Consistency Test of Cement Procedure
- The standard consistency of any cement is achieved when cement permits the Vicat plunger to penetrate to a point 33 to 35 mm from the bottom of the Vicat mould.
- First of all, take about 300 gm of cement into a tray and is mixed with a known percentage of water by weight of cement.
What is no-fines concrete?
What is No-Fines Concrete? No-Fines Concrete is a lightweight concrete made up of only coarse aggregate, cement and water by omitting fines (sand or fine aggregates) from normal concrete. Advantages, limitations and mix proportions of no-fines concrete is discussed.
Why is there no capillary movement in no fines concrete?
In no-fines concrete no capillary movement of water can take place because of the large size of continuous pores and rough, open-textured structure. Due to the same reason this concrete has high water permeability. No-fines concrete exhibits little cohesion and shows no segregation.
What happens if you mix concrete with too little water?
Too little water may leave loose aggregate inside the concrete and too much of water may cause the cement paste to flow and segregate. It is better to wet the aggregate before adding cement and water. The concrete should then be mixed thoroughly till all the particles are coated.
What is the compressive strength of no fines concrete?
The compressive strength of no-fines concrete varies between 1.4 MPa to about 14 MPa. Table 12.5 shows the compressive strength of no-fines concrete. The bond strength of no-fines concrete is very low and, therefore, reinforcement is not used in conjunction with no-fines concrete.