MCQOPTIONS
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MCQOPTIONS
This section includes 143 Mcqs, each offering curated multiple-choice questions to sharpen your Concrete Technology knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Concentration of water-soluble sulphates in water ___________ ppm for severe exposure. |
| A. | <150 |
| B. | 150-1500 |
| C. | 150-10000 |
| D. | >10000 |
| Answer» D. >10000 | |
| 2. |
Concentration of water-soluble sulphates in water ___________ ppm for mild exposure. |
| A. | <150 |
| B. | 150-1500 |
| C. | 150-10000 |
| D. | >10000 |
| Answer» B. 150-1500 | |
| 3. |
The quality of concrete, specifically a ____________ cement content, is the best protection against sulphate attack. |
| A. | High |
| B. | Medium |
| C. | Low |
| D. | Very low |
| Answer» B. Medium | |
| 4. |
For concrete exposed to a very aggressive environment the w/c should be lower than __________ |
| A. | 1 |
| B. | .5 |
| C. | .4 |
| D. | .8 |
| Answer» D. .8 | |
| 5. |
The addition of a pozzolanic admixture such as fly ash reduces the ____________ |
| A. | C3S |
| B. | C3A |
| C. | C2S |
| D. | C4AF |
| Answer» C. C2S | |
| 6. |
Consider a two-dimensional flow through isotropic soil along x direction and z direction. If h is the hydraulic head, the Laplace’s equation of continuity is expressed as |
| A. | \(\frac{{\delta h}}{{\delta x}} + \frac{{\delta h}}{{\delta z}} = 0\) |
| B. | \(\frac{{{\delta ^2}h}}{{\delta {x^2}}} + \frac{{{\delta ^2}h}}{{\delta x\delta z}} + \frac{{{\delta ^2}h}}{{\delta {z^2}}} = 0\) |
| C. | \(\frac{{{\delta ^2}h}}{{\delta {x^2}}} + \frac{{{\delta ^2}h}}{{\delta {z^2}}} = 0\) |
| D. | \(\frac{{\delta h}}{{\delta x}} + \frac{{\delta h}}{{\delta x}}\frac{{\delta h}}{{\delta x}}\frac{{\delta h}}{{\delta z}} + \frac{{\delta h}}{{\delta z}} = 0\) |
| Answer» D. \(\frac{{\delta h}}{{\delta x}} + \frac{{\delta h}}{{\delta x}}\frac{{\delta h}}{{\delta x}}\frac{{\delta h}}{{\delta z}} + \frac{{\delta h}}{{\delta z}} = 0\) | |
| 7. |
A stratum of soil consists of three layers of equal thickness. The permeability of both the top and the bottom layers is 10-4 cm/s and that od middle layer is 10-3 cm/s ; then the value of the horizontal coefficient of permeability for the entire composite of the soil layers is |
| A. | 2 × 10-4 cm/s |
| B. | 3 × 10-4 cm/s |
| C. | 4 × 10-4 cm/s |
| D. | 5 × 10-4cm/s |
| Answer» D. 5 × 10-4cm/s | |
| 8. |
Approximate ratio of the permeability of two clay soils, having D10 values of 0.8 mm and 0.4 mm respectively, is |
| A. | 2 |
| B. | 4 |
| C. | 8 |
| D. | 16 |
| Answer» C. 8 | |
| 9. |
Determine the value of critical hydraulic gradient for a loose deposit of sand having a void ratio of 0.67 and specific gravity of 2.67. |
| A. | 5 |
| B. | 1 |
| C. | 10 |
| D. | 2 |
| E. | 12 |
| Answer» C. 10 | |
| 10. |
Falling head permeability test is carried out on a soil specimen having cross-sectional area of 60 sq.cm. and height of 15 cm. The water level in the stand pipe of diametre of 0.5 cm drops from 100 cm to 40 cm in half an hour. What is the coefficient of permeability (cm/s)? |
| A. | 2.49 × 10-5 |
| B. | 2.50 × 10-3 |
| C. | 3.38 × 10-4 |
| D. | 5.09 × 10-5 |
| Answer» B. 2.50 × 10-3 | |
| 11. |
In a three-layered soil system the thicknesses of the top and bottom layers each has half the thickness of the middle layer. The coefficients of permeability of top and bottom layers each are double the coefficient of permeability k of the middle layer. When horizontal flow occurs, the equivalent coefficient of permeability of the system will be |
| A. | 1.5 k |
| B. | 3.0 k |
| C. | 4.5 k |
| D. | 6.0 k |
| Answer» B. 3.0 k | |
| 12. |
Consider the following statements:1. In a sedimentary soil deposit, permeability in the horizontal direction is greater than that in the vertical direction.2. Permeability of two sand specimens having equal void ratio will be always same.Which of the above statements is / are correct? |
| A. | 2 only |
| B. | 1 only |
| C. | Neither 1 nor 2 |
| D. | Both 1 and 2 |
| Answer» C. Neither 1 nor 2 | |
| 13. |
An anisotropic soil deposit has coefficient of permeability in vertical and horizontal directions as kz and kx, respectively. For constructing a flow net, the horizontal dimension of the problem’s geometry is transformed by a multiplying factor of |
| A. | \(\frac{{{k_z}}}{{{k_x}}}\) |
| B. | \(\frac{{{k_x}}}{{{k_z}}}\) |
| C. | \(\sqrt {\frac{{{k_z}}}{{{k_x}}}} \) |
| D. | \(\sqrt {\frac{{{k_x}}}{{{k_z}}}}\) |
| Answer» D. \(\sqrt {\frac{{{k_x}}}{{{k_z}}}}\) | |
| 14. |
Permeability tests were carried out on the samples collected from two different layers as shown in the figure (not drawn to the scale). The Relevant horizontal (kh) and vertical (kv) coefficients of permeability are indicated for each layer.The ratio of the equivalent horizontal to vertical coefficients of permeability is |
| A. | 37.29 |
| B. | 80.2 |
| C. | 68.25 |
| D. | 0.03 |
| Answer» B. 80.2 | |
| 15. |
If coefficient of permeability of a soil is 10-7 cm/sec. then the soil is:- |
| A. | Gravel |
| B. | Sand |
| C. | Silt |
| D. | Clay |
| Answer» E. | |
| 16. |
Consider the following statements1. The static cone penetration test is unsuitable for layered deposits of sands, silts and clays.2. The results of groundwater investigation are recorded as water-table contours over the site.3. Closed Piezometer is used to measure pore water pressure in soils having low permeability.Which of the above statements are correct? |
| A. | 1, 2 and 3 |
| B. | 1 and 2 only |
| C. | 2 and 3 only |
| D. | 1 and 3 only |
| Answer» E. | |
| 17. |
A tracer takes 100 days to travel from Well-1 to Well-2 which are 100 m apart. The elevation of water surface in Well-2 is 3 m below that in Well-1. Assuming porosity equal to 15%, the coefficient of permeability (expressed in m/day) is |
| A. | 0.3 |
| B. | 0.45 |
| C. | 1 |
| D. | 5 |
| Answer» E. | |
| 18. |
Consider the following statements regarding flow net:1. It helps determine the quantity of seepage.2. It helps determine the upward lift below a hydraulic structure.3. It is applicable to rotational flow only.Which of the above statements are correct? |
| A. | 1 and 2 only |
| B. | 1 and 3 only |
| C. | 2 and 3 only |
| D. | 1, 2 and 3 |
| Answer» B. 1 and 3 only | |
| 19. |
Consider the following statements:1. Soil with high void ratio has always more coefficient of permeability than the soil with lower void ratio.2. Constant head permeability test is used for fine grained soil.3. As temperature increases, the coefficient of permeability of soil also increases.4. As the specific surface area of soil particle increases, the coefficient of permeability decreasesWhich of these statements are correct? |
| A. | 1 and 2 |
| B. | 2 and 3 |
| C. | 1, 3 and 4 |
| D. | 4 and 1 |
| Answer» D. 4 and 1 | |
| 20. |
According to Darcy's law, the formula for the amount of water to be discharged from the soil is- (while Q = water content, K = permeability coefficient, i - fluid gradient and A = longitudinal area). |
| A. | Q = Ki / A |
| B. | Q = KA i |
| C. | Q = Ai / K |
| D. | Q = KA / i |
| Answer» C. Q = Ai / K | |
| 21. |
A sample of clay and a sample of sand have the same specific gravity and void ratio. Their permeabilities would differ because |
| A. | Their porosities would be different |
| B. | Their degrees of saturation would be different |
| C. | Their densities would be different |
| D. | The size ranges of their voids would be different |
| Answer» E. | |
| 22. |
An extended layer of soil with homogeneous rounded grains has 0.07 mm. The constant to be adopted to determine its permeability has been recommended as 750. What is its permeability? |
| A. | 2.583 m/day |
| B. | 2.857 m/day |
| C. | 3.244 m/day |
| D. | 3.675 m/day |
| Answer» E. | |
| 23. |
For the constant head permeability test set-up shown in the following figure, the following observations were made. L = 30 cm, Area of the specimen = 175 sq. cm, Constant head difference = h = 50 cm and water collected in a period of 5 min is 350 cu. cm. the hydraulic conductivity cm/s is |
| A. | 0.004 |
| B. | 0 |
| C. | 0.04 |
| D. | 0.24 |
| E. | 0.024 |
| Answer» B. 0 | |
| 24. |
Falling head permeability test is used for |
| A. | sandy soil |
| B. | clayey soil |
| C. | silty sand |
| D. | sandy gravel |
| Answer» C. silty sand | |
| 25. |
A soil has discharge velocity of 5 × 10–7 m/s and a void ratio of 0.5. Its seepage velocity will be |
| A. | 15 × 10–7 m/s |
| B. | 10 × 10–7 m/s |
| C. | 20 × 10–7 m/s |
| D. | 30 × 10–7 m/s |
| Answer» B. 10 × 10–7 m/s | |
| 26. |
if the permeability of a soil is 0.8 mm/sec, the type of soil is: |
| A. | gravel |
| B. | sand |
| C. | silt |
| D. | clay |
| Answer» C. silt | |
| 27. |
Estimate the value of k of a soil with an effective diameter of 0.2 mm: |
| A. | 0.5 cm/sec |
| B. | 0.04 cm/sec |
| C. | 0.05 mm/sec |
| D. | 0.57 mm/sec |
| Answer» C. 0.05 mm/sec | |
| 28. |
Consider the following statements regarding permeability of soils:1. Permeability of coarse grained soil is inversely proportional to the specific surface at a given porosity.2. Direct measurement of permeability of a soil specimen at any stage of loading in odometer test can be made only in fixed-ring type odometer.3. The permeability of an aquifer increases with decrease in temperature of water moving through it.Which of the above statements are correct? |
| A. | 1 and 2 only |
| B. | 1 and 3 only |
| C. | 2 and 3 only |
| D. | 1, 2 and 3 |
| Answer» B. 1 and 3 only | |
| 29. |
Grain size, viscosity, temperature and void ratio are the important factors influencing which of the following property of soil? |
| A. | Infiltration |
| B. | Seepage |
| C. | Permeability |
| D. | Porosity |
| Answer» D. Porosity | |
| 30. |
If the hydraulic gradient is unity, then what is the ratio of flow across unit area of soil called? |
| A. | Coefficient of discharge |
| B. | Coefficient of viscosity |
| C. | Coefficient of seepage |
| D. | Coefficient of permeability |
| Answer» E. | |
| 31. |
If the capillary rise in soil A with an effective size of 0.02 mm was 60 cm, then what would be the capillary rise in the similar soil B with an effective size of 0.04 mm? |
| A. | 30 cm |
| B. | 20 cm |
| C. | 40 cm |
| D. | 35 cm |
| Answer» B. 20 cm | |
| 32. |
In the falling head permeability test, in the duration of 3 hours the initial head of 1000 mm is dropped to 350 mm. The diameter of the stand pipe is 0.5 cm. The length and diameter of the soil specimen are 20 cm and 10 cm respectively. What is the coefficient of permeability (mm/s) of the soil? |
| A. | 4.86 × 10-8 |
| B. | 4.86 × 10-5 |
| C. | 4.86 × 10-3 |
| D. | 5.23 × 10-5 |
| Answer» C. 4.86 × 10-3 | |
| 33. |
According to Darcy’s law for flow through porous media, the velocity is proportional to |
| A. | Effective stress |
| B. | Hydraulic gradient |
| C. | Cohesion |
| D. | Stability number |
| Answer» C. Cohesion | |
| 34. |
Consider the following statements:(i) Organic matter increases the permeability of a soil(ii) Entrapped air decreases the permeability of a soilWhich of these statements is / are correct? |
| A. | Only (i) |
| B. | Only (ii) |
| C. | Both (i) and (ii) |
| D. | Neither (i) or (ii) |
| Answer» C. Both (i) and (ii) | |
| 35. |
Consider the following assumptions as regards the field permeability test:1. The flow is laminar and Darcy’s law is valid.2. The flow is horizontal and uniform at all points in the vertical section.3. The velocity of flow is proportional to the ‘tangent magnitude’ of the hydraulic gradient.Which of the above assumptions are correct? |
| A. | 1 and 2 only |
| B. | 1 and 3 only |
| C. | 2 and 3 only |
| D. | 1, 2 and 3 |
| Answer» E. | |
| 36. |
The capillarity-permeability test may be also called as ___________ |
| A. | Vertical capillarity test |
| B. | Horizontal capillarity test |
| C. | Capillary test |
| D. | Coefficient of permeability test |
| Answer» C. Capillary test | |
| 37. |
Terzhagi’s formula can be applied for_________ |
| A. | Uniform sand |
| B. | Clay soil |
| C. | Coarse-grained soil |
| D. | Fine-grained soil |
| Answer» B. Clay soil | |
| 38. |
Coefficient of permeability of soil can be determined by which of the following method? |
| A. | Laboratory methods |
| B. | Field methods |
| C. | Indirect methods |
| D. | All of the mentioned |
| Answer» E. | |
| 39. |
The hydraulic gradient (i), used in capillary-permeability test is ____________ |
| A. | h0+hc/x |
| B. | h0/x |
| C. | h0+hc |
| D. | hc/x |
| Answer» B. h0/x | |
| 40. |
The saturation in capillary-permeability is assumed to be ___________ percentage. |
| A. | 0 |
| B. | 50 |
| C. | 75 |
| D. | 100 |
| Answer» E. | |
| 41. |
The structural arrangement of soil Particle vary depending upon ______________ |
| A. | Method of deposition and Compacting the soil mass |
| B. | Degree of saturation |
| C. | None of the mentioned |
| D. | All of the mentioned |
| Answer» B. Degree of saturation | |
| 42. |
What will be its average permeability perpendicular to the bedding plane if a soil deposit has three layers of soil? The permeability of the second layer is twice that of the first layer and the permeability of the third layer is thrice that of the first layer. The thickness of each layer is 5m. |
| A. | 11k |
| B. | 18k |
| C. | \(\frac{11}{18}k\) |
| D. | \(\frac{18}{11}k\) |
| Answer» E. | |
| 43. |
A soil deposit has three layers of soil. The permeability of the second layer is twice that of the first layer and the permeability of the third layer is thrice that of the first layer. The thickness of each layer is 5m. What will be its average permeability parallel to the bedding plane? |
| A. | k |
| B. | 2k |
| C. | 3k |
| D. | 4k |
| Answer» C. 3k | |
| 44. |
Each layer of stratified soil deposit has its own coefficient of permeability. |
| A. | True |
| B. | False |
| C. | May be True or False |
| D. | Can't say |
| Answer» B. False | |
| 45. |
How do degree of saturation effect permeability of soil? |
| A. | By reducing the pore size |
| B. | By entrapping air in the voids |
| C. | Not allowing soil particles to move freely |
| D. | By changing the void ratio |
| Answer» C. Not allowing soil particles to move freely | |
| 46. |
Each layer of soil layer has its own value of ___________ |
| A. | Degree of saturation |
| B. | Coefficient of permeability |
| C. | Capillary head |
| D. | All of the mentioned |
| Answer» C. Capillary head | |
| 47. |
The laboratory observation falling head test consist of measurements of ____________ |
| A. | h1 at an interval of t1 and h2 at an interval of t2 |
| B. | Only t1 and t2 |
| C. | None of the mentioned |
| D. | All of the mentioned |
| Answer» B. Only t1 and t2 | |
| 48. |
The possible directions of flow of the soil deposit with respect to the bedding planes are ___________ |
| A. | Parallel and Perpendicular |
| B. | Inclined |
| C. | None of the mentioned |
| D. | All of the mentioned |
| Answer» B. Inclined | |
| 49. |
The unit of coefficient of absolute permeability(K) is ____________ |
| A. | Kg/cm |
| B. | m/s² |
| C. | m² |
| D. | All of the mentioned |
| Answer» D. All of the mentioned | |
| 50. |
The Jodhpur permeameter, was designed by ___________ |
| A. | Louden |
| B. | Kozney |
| C. | Alam Singh |
| D. | Poiseullie’s |
| Answer» D. Poiseullie’s | |