STRUCTURAL ENGINEERING Flashcards
E means
Modulus of Elasticity = Stress / Strain
Metals
▪ Cast Iron
▪ Steel
▪ Aluminum
WHAT DOES A STRUCTURAL ENGINEER DO? 1
Design of Buildings and Infrastructures
Depends on the type of material and type of force (tension or compression)
STRENGTH
moving loads (e.g. occupants, vehicles)
Live Loads (transient):
FORCES IN STRUCTURAL ELEMENTS
Tension, Compression, Bending, Torsion,
Stress
= Force/Area
DESIGN PROCESS IN STRUCTURAL ENGINEERING
- Select material for construction
- Determine the appropriate structural system for a particular case
- Determine forces acting on a structure
- Calculate the size of members and connections to avoid failure (collapse) or excessive
deformation
process of determining location, material, and size of structural elements to resist
forces acting in a structure
design
▪ Property related to deformation
STIFFNESS (RIGIDITY)
carry bending in two directions. A concrete flat slab is an example
plates
▪ Testing and evaluation of solution
▪ Experimental testing (prototype) or field tests
▪ Peer evaluation
PROVIDING STABILITY FOR LATERAL LOADS
Racking Failure of Pinned Frame, Braced Frame, Infilled Frame, Rigid Joints
▪ Net force at a point in a structure = zero (summation of forces = zero)
▪ Statement of equilibrium
Strain
= DL / Lo
Axial Stiffness
= T/DL
Percentage: Gravel or Crushed Stones
41
▪ Stiffer structural elements deform less under the same applied load
STIFFNESS (RIGIDITY)
▪ Net force at a point is determined using a force polygon to account for magnitude
and direction
EQUILIBRIUM OF FORCES (STATICS)
ENGINEERING DESIGN PROCESS
▪ Identify the problem
▪ Explore alternative solutions
▪ Analyze and design one or more viable solutions
▪ Testing and evaluation of solution
▪ Build solution using available resources (materials, equipment, labor)
MATERIALS USED IN CIVIL ENGINEERING
▪ Stone and Masonry
▪ Metals
▪ Concrete
▪ Wood
▪ Fiber-Reinforced Plastics
Explore alternative solutions
▪ Research past experience
▪ Brainstorm
▪ Preliminary design of most promising solutions
Percentage: Sand
26
▪ Statement of equilibrium
EQUILIBRIUM OF FORCES (STATICS)
self-weight of structure and attachments
Dead Loads (permanent)
Moment of Force
= Force x Distance
element in which one dimension is much
greater than the other two and the applied loads are usually normal to the main
axis of the element.
beams
Percentage: Cement
11
Percentage: Air
6
BENDING STIFFNESS
= Force / Displacement
TYPES OF STRESS – STRAIN BEHAVIOR
Linear, Non-linear, Elastic-plastic, Non-linear plastic
TYPICAL STRUCTURAL SYSTEMS
Arch, Truss, Frame
A Structural Engineer designs the [] and [] in buildings, bridges, stadiums, tunnels, and other civil engineering works (bones)
structural systems, structural elements
WHAT DOES A STRUCTURAL ENGINEER DO? 3
Shoring & Excavation
WHAT DOES A STRUCTURAL ENGINEER DO? 2
Retrofit of Old and Historic Buildings
▪ Stiffness depends on [], [], and []
type of material (E), structural shape, structural configuration
STIFFNESS (RIGIDITY)
▪ Two main types of stiffness
▪ Axial stiffness
▪ Bending stiffness
STIFFNESS (RIGIDITY)
derive their strength from their
form and carry forces in compression in two directions
shells
elements that carry only axial force (compression) or both axial
force and bending
columns
WHAT DOES A STRUCTURAL ENGINEER DO?4
Repair and Inspection of Damaged Buildings
Global stability
Sliding, Overturning
Forces are a type of quantity called vectors - Defined by magnitude and direction
EQUILIBRIUM OF FORCES (STATICS)
A [] simply supported beams, bending under an evenly distributed load
statistically determinate
carry forces in compression in one direction only, which is why it is
appropriate to build [] out of masonry. They are designed by ensuring
that the line of thrust of the force remains within the depth of the []
arch
FORCES ACTING IN STRUCTURES
▪ Forces induced by gravity
▪ Forces induced by wind
▪ Forces induced by earthquakes
▪ Forces induced by rain/snow
▪ Fluid pressures
▪ Others
Ability to withstand given stress without failure
STRENGTH
Percentage: Water
16
structure comprising members and connection points or nodes.
trusses
CONCRETE COMPONENTS
▪ Sand (Fine Aggregate)
▪ Gravel (Coarse Aggregate)
▪ Cement (Binder)
▪ Water
▪ Air