Bissoy.com
Doctors Medicines MCQs Q&A

Which of the following statements are correct regarding Westergard’s concept for temperature stresses? 1. During the day, the top of the pavement slab gets heated under the sunlight when the bottom of the slab becomes hot 2. During summer season as the mean temperature of the slab increases, the concrete pavement expands towards the expansion joints 3. Due to frictional force at the interface, compressive stress is developed at the bottom of the slab as it tends to expand.

Which of the following statements are correct regarding Westergard’s concept for temperature stresses? 1. During the day, the top of the pavement slab gets heated under the sunlight when the bottom of the slab becomes hot 2. During summer season as the mean temperature of the slab increases, the concrete pavement expands towards the expansion joints 3. Due to frictional force at the interface, compressive stress is developed at the bottom of the slab as it tends to expand. Correct Answer 2 and 3 only

Temperature stresses are developed in rigid pavements due to variations in temperature. This is caused by the following two factors:

1. Seasonal variation in temperature and

2. Daily Variation in temperature

Statement I – False

Daily variation in temperature:

It causes warping stress due to the temperature gradient across the slab thickness.

During the day, the top surface will try to expand but the weight of the slab will resist and hence, compression will be developed on the top surface and tension will develop at the bottom surface.

During the night, the bottom surface will be at a higher temperature and hence, has a tendency to expand, but the weight of the slab will resist it, generating compression at the bottom surface and tension at the top surface.

During Day Time:

During Night Time: 

∴ During the day the top of the pavement slab gets heated under the sunlight when the bottom of slab still remains relatively colder.

Statement-II & III True

Seasonal Variation in temperature

It causes frictional stresses due to the overall change in the temperature of the slab.  During summer season as the mean temperature of the slab increases, the concrete pavement expands towards the expansion joints and in winter season opposite phenomena occurred as shown in the figure:

Frictional Stresses:

[ alt="F2 A.M 18.6.20 Pallavi D 7" src="//storage.googleapis.com/tb-img/production/20/06/F2_A.M_18.6.20_Pallavi_D%207.png" style="width: 386px; height: 155px;">

 

[ alt="F2 A.M 18.6.20 Pallavi D 8" src="//storage.googleapis.com/tb-img/production/20/06/F2_A.M_18.6.20_Pallavi_D%208.png" style="width: 363px; height: 151px;">

Related Questions

The diagram shows the survey on a sample of 197 persons with reference to their preferences for three seasons that is winter, summer, and spring. 120 persons like spring season, 100 like Winter Season, and 90 like summer season. 50 persons like both spring and winter season only, 25 like both summer and winter season only, and 18 like both spring and summer season only. 10 persons like all three seasons. How many persons like only the winter season?
A group of 463 people were asked to vote for their favourite season among four seasons(rainy, summer, spring and winter) Rainy season got 130 votes. whereas summer season got 100 votes. winter season got 53 more votes than summer season. Spring season got 80 votes. Which season is liked by most people?
A cc slab of thickness 20 cm is constructed over a base of granular material with a modulus of reaction 10 kg/cm3. The maximum temperature differential between the top and bottom of the slab is found to be 19°C during summer day and night. The spacing between transverse joints is 8 m and the spacing between longitudinal joints is 4 m. The design wheel load is 5100 kg, radius of contact area is 15 cm, Poisson’s ratio is 0.15, modulus of elasticity is 3×105 kg/cm2, the thermal coefficient is 10 ×10-6 /°C and the coefficient of friction is 1.5. Using the above information, find the worst combination of stresses at the edge of the pavement.
Which of the following statements are true with regard to tropical monsoon climate?
I. Temperatures range from 32° C in the hot season to about 15° C in the cool season
II. Annual rainfall varies greatly
III. The climate is best developed in the southern continents
IV. It consists of three main seasons i. e. cool, dry season; hot, dry season; hot, wet season
Engines are rated at specified conditions. Then which of the following statements are correct? 1. Power developed increases as local temperature increases. 2. Power developed increases as local temperature decreases 3. Power developed is not dependent on local temperature. 4. Power developed increases as local atmospheric pressure increases. 5. Power developed increases as local atmospheric pressure decreases.
Match List-I with List-II and select the correct answer using the code given below the Lists: List I (Low-Latitude Climate) List I (Characteristic) A. Wet Equatorial 1. Uniform temperatures, mean near 27°C  B. Monsoon and trade wind coastal 2. Marked temperature cycle with very high temperature before the rainy season C. Wet-dry tropical  3. Temperatures show an annual cycle with a high temperature in the high-Sun season Strong temperature cycle. with intense temperature during the high-Sun season  D. Dry tropical 4. Strong temperature cycle, with intense temperature during the high-Sun season
Consider the following statements regarding pavements: (i) Rigid pavements have good night visibility than flexible pavements. (ii) It is possible to make cross-cutting of the rigid pavement. (iii) In a flexible pavement, any deformation in the top layers is transferred to the under-laid layers; but, in rigid pavements, there is slab or beam action due to which any deformation is only in the top layer of the concrete slab. Which of the above statements are correct?
Consider the following statements regarding pavements: 1. Rigid pavements are more suitable than flexible pavements for stage construction. 2. Rigid pavements are more affected by temperature variations than flexible pavements. 3. In a flexible pavement, any deformation in the top layers is transferred to under- laid layers; but, in rigid pavements, there is slab or beam action due to which any deformation is only in the top layer of the concrete slab. Which of the above statements are correct?
What will be the critical combination of stresses at the edge during winter if the following stresses have been calculated for the pavement? Load stress = 35.67 kg/cm2 Warping stress = 30.31 kg/cm2 Frictional stress = 0.89 kg/cm2
What will be the critical combination of stresses at the corner if the following stresses have been calculated for the pavement? Load stress = 30.50 kg/cm2 Warping stress = 8.56 kg/cm2 Frictional stress = 0.77 kg/cm2