IV B.Tech I Semester Regular/Supplementary Examinations, Nov/Dec- 2014

Transcription

1 Set No. 1 1 a) What is dewatering? What are the objectives of dewatering? b) Explain in detail about the Electro-osmosis theory with neat sketch. 2 a) What are different types of grouts available and what are its properties? b) What is the role of grouting in ground improvement? Distinguish between suspension grout and solution grout. 3 a) Describe the densification methods of cohesion less soils. b) Explain the impact at the ground surface method of densification and also list out its advantages and disadvantages. 4 a) In what site conditions stone columns are preferred? If the soil is very soft clay would you recommend the stone column method? b) Explain in detail the preloading method of ground improvement and methods of accelerating the effectiveness with the help of neat sketches. 5 a) Explain the methods and proportioning techniques for mechanical soil b) Discuss the suitability and application of lime 6 a) Explain the design considerations involved in reinforced earth retaining walls. b) What is reinforced earth? How does it differ in action from reinforced earth retaining walls? 7 a) Explain how geotextiles are used in slope stabilization and in embankment construction in soft soils b) Describe the different forms of geogrids and state their functions in the 8 a) Enumerate different design consideration of foundations on expansive soils. b) What are the measures taken to prevent the swelling of expansive soils?

2 Set No. 2 1 a) Describe with neat sketches about the dewatering by Educator system. What are the advantages and disadvantages? b) Explain different drains with neat sketch. 2 a) What is hydraulic fracturing? What is it uses? Where it can be used? b) Differentiate between the compaction grouting and displacement grouting. 3 a) Describe the method of densification by blasting. b) Explain the methods of vibriflotation stage wise as applied to granular soils for compaction at depth with neat sketches. 4 a) Explain the construction procedure of stone columns? b) Explain how soil-lime is designed. 5 a) Describe soil-cement What are the factors affecting strength of soil-cement mixes? b) Discuss the use of bitumen as stabilizer for cohesive and non cohesive soils. Bring out the differences between two. 6 a) Explain various modes of failure of a reinforced earth walls and the methods of calculating the factor of safety against them. b) Write short notes on in situ ground reinforcement. 7 a) List out the applications of geotextiles based on separation and reinforcement functions. b) Describe the different forms of geomembranes and state their functions in the stabilization of soils. 8 a) What are the various problems encountered for foundations constructed on expansive soils? b) What is swelling pressure? How can we estimate swelling pressure in laboratory?

3 Set No. 3 1 a) Describe with neat sketches about the dewatering by sumps and ditches? b) Explain vacuum dewatering system. 2 a) What aspects would you consider in deciding on the spacing and depth of injection holes for grout curtain below a dam? b) List out physical characteristics of grouting liquid relevant to engineering applications 3 a) Explain the objectives of densification in cohesion less soils. b) Describe the soil properties and their limits which govern the ground improvement in granular soils. 4 a) Explain the ground modification by thermal method b) Explain the principle behind the ground modification with lime columns? 5 a) What is the principle behind the stabilization with sodium silicate? b) Describe any method of chemical 6 a) What are the components of reinforced earth? Illustrate with neat sketches the various practical applications where reinforced earth is used. b) How can the horizontal spacing of reinforcing strips are derived for material in a retaining wall. 7 a) Distinguish between drainage and filtration function of geotextiles. Mention the applications based on each function. b) Write note on common nomenclature of geosynthetics. 8 a) What is Cohesive-Non Swelling layer? When do you use it and what are its limitations. b) What are the factors influencing the swelling behavior of soil?

4 Set No. 4 1 a) Explain the criteria for selection of fill material around drains b) Describe single, multi stage well points dewatering systems with neat sketches 2 a) Write a note on different types of grouting techniques b) Mention the applications of grouting. 3 a) Explain in detail, how the heavy tamping technique can be used to improve the ground. In what type of soil and ground conditions you recommend this technique. b) What are different in situ densification methods available for granular soils? 4 a) Write a note on preloading technique by mentioning the advantages and disadvantages. b) Explain the merits and demerits of stone columns and sand drains. 5 a) Explain different applications of mechanical b) Explain how the engineering properties of soil are modified by bituminous 6 a) Explain the basic mechanism of reinforced earth b) How is soil selected in reinforced earth application? What are popular reinforcing materials? Explain. 7 a) Explain the advantages and disadvantages of woven and non woven geotextiles. b) Explain various tests conducted on geotextiles to assess their properties. 8 a) Explain briefly various methods that are to be used to improve expansive soils for foundations. b) Discuss the principle and functioning of under-reamed piles.

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