Prestressed Concrete Structures Multiple Choice Questions on “Introduction and General Aspects”.
1. The logical steps to be found before beginning the construction of any prestressed concrete structures are ____________
a) Planning analysis and design
b) Stress analysis
c) Strain analysis
d) Prestressed analysis
Clarification: Planning, analysis and design are the logical steps to be followed before beginning the construction of any prestressed concrete structures from ancient times; construction of a structure has always been one of the most fascinating challenges to man ingenuity.
2. The architectural capabilities constitutes the essence of the ____________
a) Conceptual aspects of structures
b) Chemical aspects of structures
c) Structural aspects of structures
d) Time aspects of structures
Clarification: Architectural capabilities constitutes the essence of the conceptual and aesthetic aspects of structures and the domain of construction activity involves several known and unknown features such as management of materials and labour, mobilization of suitable cost effective techniques, treacherous foundations problems adverse water conditions, planning and scheduling of the construction process to a time based frame, constant interaction with the design engineer, architect, site engineer, construction workers and ability to take sound and daring decisions at times of crisis.
3. Which type of engineers should be more conceptual and visual?
a) Construction engineers
b) Site engineers
c) Practical engineers
Clarification: Practical engineers must be more conceptual than mere perceptual, more creative than mere analytical and more visual than mere mathematical and construction engineers should have wide experience involving several types of structures rather than isolated narrow specialization and expertise and original skill are attained from relentless understanding and practice rather than mere theoretical knowledge and good and sound judgment are attained from wide practical experience and often experience comes from bad judgment.
4. The sub structure in every structure is known as ____________
Clarification: Every structure has a foundation(sub structure) which may either be shallow type, like isolated and combined footings, or a monolithic raft where the loads to be transferred on solids of low bearing capacity and large, as in the case of multistoried buildings.
5. Deep foundation depends upon the type of ____________
a) Super structure
Clarification: Deep foundations are generally piles, caissons and walls depending upon the type of super structure and the soil conditions and the most common types of piles used are: Timber, Steel, Reinforced concrete and prestressed concrete.
6. The precast piles of reinforced concrete are widely used types for ____________
a) Plastic solids
b) Wet soils
c) Clayey soils
d) Hard soils
Clarification: Precast piles of reinforced or prestressed concrete are the most widely used types for clayey soils of low bearing capacity and well foundation also referred to as open caissons are the most common types generally adopted for major bridges in India, where the soil strata comprises sand or stiff clay.
7. The pneumatic caisson foundations consisting of ____________
a) Concrete cutting
b) Steel cutting
c) Aluminium cutting
d) Block cutting
Clarification: Pneumatic caisson foundations consisting of steel cutting base and concrete pier are adopted for deep foundations in watery situation and the reader may refer to the monograph design of bridges by the author for detailed descriptions and structural design of piles, wells and caissons.
8. One of the following elements of super structure is?
a) Aircraft hanger
b) Water vessels
c) Hydrogen container
d) Liquid container
Clarification: A super structure comprises a floor or roof of a building, bridge deck, large capacity liquid retaining structure, aircraft hanger, nuclear reactor containment vessel, offshore oil drilling platform and a host type of structures and there is no single form of design which would always be more economical.
9. There is no single form of design which would always be most?
a) Long lasting
Clarification: There is no single form of design which would always be most economical and it is only by computing a few tentative with a knowledge of the site conditions, availability of skilled labour, materials and machinery, time frame fixed for completion of the project and purpose of the intended structure that one can reasonably arrive at an economical solution.
10. The specifications for batching and mixing of concrete are measured to an accuracy of ____________
Clarification: Concrete of uniform quality can be produced only when the ingredients are accurately measured for each batch and good specification requires that batching is done by weight rather than by volume weight batching ensures greater accuracy, simplicity and flexibility and specifications require that the materials – cement, aggregates and water measured to an accuracy of + or – 0.5%.