Practical Interview Question for civil Engineers | civil Engineering
What is “preset” during installation of bridge bearings?
“Preset” is a method to reduce the size of upper plates of sliding bearings in order to save the material cost. The normal length of a upper bearing plate should be composed of the following components: length of bearing + 2 x irreversible movement + 2 x reversible movement. Initially the bearing is placed at the mid-point of the upper bearing plate without considering the directional effect of irreversible movement.
However, as irreversible movement normally takes place at one direction only, the bearing is displaced/presetted a distance of (irreversible movement/2) from the mid-point of bearing in which the length of upper plate length is equal to the length of bearing + irreversible movement + 2 x reversible movement. In this arrangement, the size of upper plate is minimized in which irreversible movement takes place in one direction only and there is no need to include the component of two irreversible movements in the upper plate.
What is the function of shear keys in the design of retaining walls?
In determining the external stability of retaining walls, failure modes like bearing failure, sliding and overturning are normally considered in design. In considering the criterion of sliding, the sliding resistance of retaining walls is derived from the base friction between the wall base and the foundation soils. To increase the sliding resistance of retaining walls, other than providing a large self-weight or a large retained soil mass, shear keys are to be installed at the wall base. The principle of shear keys is as follows:
The main purpose of installation of shear keys is to increase the extra passive resistance developed by the height of shear keys. However, active pressure developed by shear keys also increases simultaneously. The success of shear keys lies in the fact that the increase of passive pressure exceeds the increase in active pressure, resulting in a net improvement of sliding resistance.
On the other hand, friction between the wall base and the foundation soils is normally about a fraction of the angle of internal resistance (i.e. about 0.8φ ) where φ is the angle of internal friction of foundation soil. When a shear key is installed at the base of the retaining wall, the failure surface is changed from the wall base/soil horizontal plane to a plane within foundation soil. Therefore, the friction angle mobilized in this case is φ instead of m0.8φ in the previous case and the sliding resistance can be enhanced.
What Is Steel And Properties Of Steel ?
Steel Before Acquiring The Harden State, Go Through Various Types Of Treatment And Refining Processes.
These processes include the selection of suitable scrap and or material and its treatment i.e crushing, melting, refining, blending, and fabrication.
What Is Leveling And Types Of Leveling?
(Civil Engineer Interview Question For Site Engineering Jobs)
The objects leveling:-
- To find the elevations of given points with respect to a given or assumed datum, and
- To establish points at a given or assumed datum.
- The first operation required to enable works to design while the second operation required in the setting out Of all kinds of engineering works.
- Leveling deals with measurements in a vertical plane.
Types Of Leveling:-
- Spirit Levelling (Direct Levelling)
- Trigonometric Levelling (Indirect Levelling)
- Barometric levelling
What Is Meant By DPC In Construction?
All Types Of Structures Exposed To The External Climatic Condition Are Prone To Water Ingress At Some Time In The Failure, If The Seepage Of Water Inside The Building Through Walls And Foundations Is Not Prevented Or Left Un-Treated,
Then It May Lead To Severe Damage To The Building Structure And Can Endanger Its Stability, Such Seepage Of Water From The Substructure Of The Building And Walls Should Be Completely Prevented By Constructing An Effective Damp-Proof Course. (DPC)
DPC In Building Within The Walls And Substructures And Capable Of Blocking All Types Of Water And Moisture Passages.
What Are The Type Of Load In Design Of Building
Load Acting On Building Dead Loads (DL), Live Loads (LL), Wind Load (WL), Snow Load (SL), And Earthquake Load.
What Is Meant By Safe Bearing Capacity Of Soil
(Interview Questions For Civil Engineer In Estimate Costing)
Bearing capacity is the capacity of soil to support the loads applied to the ground.
The bearing capacity of soil is the maximum average contact pressure between the foundation and the soil which should not produce shear failure in the soil
What Are The Reasons And Prevention Of Honeycombs In Concrete
Honeycombs Are Hollow Spaces And Cavities Left In Concrete Mass On Surface.
Also Inside The Concrete Mass Where Concrete Could Not Reach.
These Look Like Honey Bees Nest.
What Is Light Weight Concrete And It’s Uses
- Light weight concrete is a concrete which has density much lower than that of ordinary concrete. (300-1850)
- Maximum slump for light weight concrete limited to 100 mm
- Natural light weight aggregate used in concrete prepared by crushing and sizing natural rocks.
What Is Shrinkage Of Concrete
- Shrinkage Is the decrease in volume of concrete in the absence of load with time.
- In the plastic stage, concrete shrinks in volume due to absorption of water or loss of water.
- Due to bleeding, the surface water evaporate rapidly causing shrinkage and this uneven shrinkage causes shrinkage cracks.
- Shrinkage depends upon the efficiency of curing method as well as water cement ratio and water added.
- Shrinkage can reduce by using low water cement ratio, pre-saturated aggregate, water tight and non-absorbents.
What Is Meant By Pre-Stressed Concrete
(Interview Questions For Civil Structural Engineer)
Concrete is very strong in compression but very weak in tension, therefore concrete is reinforced with steel bars in such direction where tensile resistance has to be offered called reinforced concrete members.
A pre-stressed concrete member of concrete in which internal stresses introduced in a planned manner so that stresses resulting form the superimposed load are resist up to desired limits.
List Out Types Of Survey And Methods Of Surveying
Geodetic Surveying, Plane Surveying.
Methods Of Surveying Control Survey, Boundary Survey, Topographic Survey, Hydrographic Survey, Construction Survey Etc
Why We Provide Plinth Beam And Where?
Plinth Beam Is A Reinforced Concrete Beam Constructed Between The Wall And Its Foundation, Plinth Beam Is Provided To Prevent The Extension Or Propagation Of Crack From The Foundation Into The Wall Above When The Foundation Suffers From Settlement, And Plinth Beam Distributes The Load Of The Wall Over The Foundation Evenly.
Elements And Principle Of Building Design
(Interview Questions For Civil Structural Engineer)
- Foundation
- Plinth
- Walls And Columns
- Sills, Lintels And Chajjas
- Doors And Windows
- Floors
- Roofs
- Steps, Stairs And Lifts
- Finishing Work
- Building Services.
Definition Of Cement And Types
•Cement, grey powder which mixed with aggregate and water in order to make concrete.
•Cement is type of glue made for sticking particular substance together (it is Binder).
- 33 Grade Ordinary Portland Cement
- 43 Grade Ordinary Portland Cement
- 54 Grade Ordinary Portland Cement
- Rapid Hardening Portland Cement
- Portland Slag Cement
- Portland Pozzolana Cement (dry based)
- Hydrophobic Cement Low Heat Portland Cement
- Portland Pozzolana Cement (fly ash based)
- Low Heat Portland Cement
- Sulphate Resisting Portland Cement
How to Increase and Decrease Setting Time Of Cement
Generally Initial setting, is the time elapsed between the moment water is added to the cement to the time at which paste starts losing its plasticity.
Final setting time of cement is the time elapsed between the moment the water is added to the cement to the time at which paste has completely lost its plasticity and attained sufficient firmness to resist certain definite pressure.
It is composite material consist of cement, water, fine aggregates and discontinuous discrete fibers is known as fiber reinforced concrete.
When fibers added to the concrete, it increases various mechanical properties such as toughness, ductility, flexural resistance, tensile strength and shear resistance.