STUPIDSID
Answer any one question from Q1 and Q2
1 (a)
What are the minor compounds in Portland cement? What is their role.
6 M
1 (b)
Explain the physical properties of aggregates affecting workability of concrete.
6 M
2 (a)
What are the functions of types of admixtures?
6 M
2 (b)
Define creep of the concrete. What are the factors affecting creep of concrete.
6 M
Answer any one question from Q3 and Q4
3 (a)
State the various types of non-destructive tests carried on hardened concrete. Explain 'Impact echo test' for determination of concrete properties.
6 M
3 (b)
Describe the types of vibrators used for compaction of concrete.
6 M
Write short notes on:
4 (a) (i)
Cellular light weight concrete.
3 M
4 (a) (ii)
Self-compacting concrete.
3 M
4 (b)
Define Ferro cement. Explain the basic concepts in forming ferro-cement composites used in the construction industry.
6 M
Answer any one question from Q5 and Q6
5
Using Indian Standard recommended guidelines, design a concrete mix for a reinforced concrete structure to be subjected to the mild exposure conditions for the following requirements:
A) Stipulations for proportioning:- a) Grade designation: M30, b) Standard deviation, s=5, c) Type of cement: OPC 43 grade conforming to IS8112, d) Workability: 75 mm (slump), e) Degree of supervision: Good, f) Type of aggregate: Angular coarse aggregate, g) Maximum cement content: 450 kg/m3.
B) Test data for Materials:
a) Specific gravity of cement: 3.15, b) Specific gravity of:
i) Coarse aggregate-2.74
ii) Fine aggregate-2.74
c) Water absorption:-
i) Coarse aggregates - 0.5%
ii) Fine aggregates - 1.00%.
d) Free surface moisture:
i) Coarse aggregates - Nil (absorbed moisture also nil)
ii) Fine aggregates ?Nil
e) Sieve analysis:
i) Coarse aggregate:
A) Stipulations for proportioning:- a) Grade designation: M30, b) Standard deviation, s=5, c) Type of cement: OPC 43 grade conforming to IS8112, d) Workability: 75 mm (slump), e) Degree of supervision: Good, f) Type of aggregate: Angular coarse aggregate, g) Maximum cement content: 450 kg/m3.
B) Test data for Materials:
a) Specific gravity of cement: 3.15, b) Specific gravity of:
i) Coarse aggregate-2.74
ii) Fine aggregate-2.74
c) Water absorption:-
i) Coarse aggregates - 0.5%
ii) Fine aggregates - 1.00%.
d) Free surface moisture:
i) Coarse aggregates - Nil (absorbed moisture also nil)
ii) Fine aggregates ?Nil
e) Sieve analysis:
i) Coarse aggregate:
| IS Sieve Sizes (mm) | Analysis of Coarse Aggregate Fraction | Percentage of different Fraction | Remarks | |||
| I | II | I (60%) | II (40%) | Combined (100%) |
Confirming of Table 2 of IS 383 |
|
|
20 10 4.75 2.36 |
100 0
|
100 71.2 9.40 0 |
60 0
|
40 28.5 3.7
|
100 28.5 3.7
|
|
ii) Fine aggregate: Conforming to grading zone I
C) Design considerations:
Table 1: From IS 10262; Maximum water content per cubic meter of concrete:
| Sr. No. | Nominal Maximum Size of Aggregate | Maximum Water Content (kg) |
|
(i) (ii) (iii) |
10 20 40 |
208 186 165 |
Table 2: From IS 10262; Volume of Coarse Aggregate per Unit Volume of Total Aggregate:
|
Sr. No. (1) |
Nominal Maximum Size of Aggregate (mm) (2) |
Volume of Coarse Aggregate per Unit Volume of Total Aggregate for Different Zones of Fine Aggregate | |||
| Zone IV | Zone III | Zone II | Zone I | ||
|
(i) (ii) (iii) |
10 20 40 |
0.50 0.66 0.75 |
0.48 0.64 0.73 |
0.46 0.62 0.71 |
0.44 0.60 0.69 |
Table 3: From IS 456; Different exposure conditions for reinforced concrete:
| Sr. No. | Exposure | Minimum cement content (kg/cubic m) | Maximum free water cement radio | Minimum grade of concrete |
|
(i) (ii) (iii) (iv) (v) |
Mild Moderate Severe Very Severe Extreme |
300 300 320 340 360 |
0.55 0.50 0.45 0.45 0.40 |
M20 M25 M30 M35 M40 |
13 M
6 (a)
Write major factors affecting mix design. Explain water cement ratio.
4 M
6 (b)
Write a short note on statistical quality control of concrete.
4 M
6 (c)
Explain DOE method of mix design in brief.
5 M
Answer any one question from Q7 and Q8
7 (a)
State and explain factors affecting permeability of concrete. What measures should be taken to reduce permeability of concrete?
8 M
7 (b)
Explain in detail corrosion monitoring techniques of reinforcement and its preventive measures.
5 M
Write short notes on:
8 (a) (i)
Sulphate attack on concrete.
4 M
8 (a) (ii)
Carbonation of concrete and its determination.
4 M
8 (b)
What are the symptoms of distress of concrete?
5 M
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