structural engineering Flashcards
The four factors that determine bending in supported beam?
material used, the cross sectional characteristics of the beam , the span of the beam and the load that the beam is subjected too.
What directions are two opposing forces of tension force shown for a stationary suspended object on a string?
They point towards each other to denote equilibrium for tension on the string.
What direction arrow would denote equilibrium in compression force in a column.
Arrows would be pointing away from each other in a column
What is reaction in structural engineering?
It is force that responds to the presence of an opposing force.
what is stress?
It is presence of internal pressure at a given point within a material.
What is moment?
Force resulting in a turning effect, such as turning of nut on its thread.
How can one calculate the amount of bending taken place on a structural beam material.
One can use deflection to calculate vertical distance through which a given point on beam has moved from its original position.
Explain the process of shearing in beam in construction?
Shearing is the failure identified either as cutting or slicing which results from the pulling apart in opposite directions of beam structure that may be horizontally overlapping materials or breaking of a joist connected to column due to applied force being too strong for the connecting part.
What is dead loads?
Forces that arise through the mass of the structure itself. Also known as static load.
What is live load?
Forces which are external that move or change , also known as dynamic loads.
Lateral loads?
Resistance to loads occurring vertically particularly when it shifts. It should remain rigid.
How are structures made to resist lateral loads
structure is designed using equalizing of vertical and horizontal forces via diagonals or through use of triangulation
Explain bracing
Bracing is a method of preventing shear by adding diagonal support across corner of both ends. The support acts as compressive element and it is in tension.
Torsion
Use of bracing to prevent twisting. Stop opposing forces acting in rotational fashion.
Give two examples of beam deformations caused by bending moments.
Hogging and Sagging. Hogging is upward deformation, Sagging is downward.
Describe columns and the column types?
Columns also known as pillars or posts are vertical and support axial loads, thus experience compression. The concrete or masonry column cross -section can be square rectangle, circular or cruciform. Steel columns maybe H or Hollow section.
List foundation types
Strip foundation, Pad foundation, Raft foundation, piled foundation.
What is strip foundation properties?
it provides continuous support to load-bearing external walls.
What is raft foundation?
It is used in scenarios where the alternative would be large number of strip and or pad foundations in small area. Raft foundation takes up the whole plan area under a building.
What are piled foundations
Used for areas where ground has low strength and building is very heavy(skyscraper) They use columns pilled into the ground which help transmit the building loads safely to stronger stratum. The piles are topped by large concrete block called pile cap.
Padded foundation
provides a loading-spreading support for a column
What are types of beams in construction?
Cantilevered, Continuous and simply supported beams. Continuous beam has two or more spans in one unbroken unit. Cantilever is supported at one end only, to avoid collapse beam must be continuous over , or rigidly fixed at this support. Simply supported beam rests on supports usually located at each end of the beam.
Types of slab
Ribbed slab, Waffle slab, Two way spanning slab , one way spanning slab.
What is one way spanning slab?
This means they are supported by walls on opposite sides of the slab.
What is two way spanning slab
Slabs supported by all four walls
Weight?
Weight is force calculated by Mass multiplied by acceleration due to gravity. It is measured in Newtons.
Density
Mass over volume
Mass
Amount of matter measured in grams or kilograms
What is point load?
Load concentrated at a single point. Also known as concentrated load. example would contact area where column is supported by beam.
What is a pin and how is it signified ?
Is support allowing rotational movement without transmitting effects or moment on attached structure. It is analogous to hinge and is symbolized as unfilled cycle.
What are main form of supports?
Pined, roller and fixed
What is Roller support?
part of structure analogous to roller skates, allowing free horizontal movement. Roller symbol normally consists of two or more cycles with triangle on top .
What is fixed support?
It is support which doesn’t support movement rotation. examples are balcony. Analogy is two fingers holding a ruler at one end. or ruler supported by two fists.
