Structural Form and Load Paths Flashcards
Lateral load resisting system (LLRS)
Is the structure which resists loads that have a horizontal component, and transfers these horizontal loads to the ground.
Flooring types
- precast concrete double tees
- profiled metal decking
- rib and infill
- insitu concrete
- hollowcore
Why are connections of a structure so important?
The connections are the critical components of any structure, they are required to transfer load safely between different structural elements, and dictate the boundary conditions of the beams and columns controlling how the members resist the loads (i.e. pinned end, fixed end). The connections are often where all the detailing is, and can often be the weakest link in the structure.
shallow/deep foundations
- strip footing
- raft foundation
-piles
-caisson e.g for bridges - pile raft… limits settlement and tilting
- underpinning
Advantages of eccentric bracing over concentric bracing
Eccentrically braced frames may exhibit a more ductile characteristic and greater energy dissipation capabilities for the same material.
Rigid diaphram
A “diaphragm is rigid when the maximum lateral deformation of the diaphragm itself is equal to or less than twice the average inter-storey deflection of the vertical lateral-force-resisting elements of the associated storey at the limit state under investigation”
Flexible diaphram
A diaphragm in which the maximum lateral deformation of the diaphragm itself is more than twice the average inter-storey deflection of the lateral-force-resisting elements of the associated storey at the limit state under consideration.
When may you come across a flexible diaphram?
- cross braced light weight roof structures
- unreinforced masonry buildings
NOTE: equivalent static loading does not apply
why are bridges seismic responses complicated?
difficult to resist seismic load in the longitudinal direction
