LESSON 3 Flashcards
It consists of the weight of all materials of construction incorporated into the building or other structure, including but not limited to walls, floors, roofs, ceilings, stairways, built-in partitions, finishes, cladding, and other similarly incorporated architectural and structural items, as well as fixed service equipment, including the weight of cranes.
Dead Loads
They are those that are permanent, including the weight of the structure itself, which is sometimes called the self-weight
Dead Loads
They are loads of constant magnitude that remain in one position. They consist of the structural frameβs own weight and other loads that are permanently attached to the frame
Dead Loads
It shall be the maximum loads expected by the intended use or occupancy but in no case shall be less than the loads required by this section.
Live Loads
They are those loads produced by the use and occupancy of the building or other structure and do not include dead load, construction load, or environmental load.
Live Loads
__________, which can also be gravity loads, are those that are not as permanent as dead loads. They may or may not be acting on the structure at any given time
Live Loads
____________ are loads that may change in position and magnitude. They are caused when a structure is occupied, used, and maintained. ______________ that move under their own power,
Live Loads
Example of Live Loads
- Floor Loads
- Traffic Loads
- Impact Loads
- Longitudinal Loads
- Other live loads (Soil pressure, Hydrostatic pressure, Blast loads, thermal forces, centrifugal forces)
It is an arrangement of live loads that produces maximum possible stresses at a point in a structure or member such as a continuous beam.
Pattern or Partial Loading
It is the type of load where rain, flood, earthquake, and wind loads are categorized.
Environmental Loads
It entails the selection of a cross section that will safely and economically resist the applied loads. Economy usually means minimum weight or the minimum amount of steel.
The design of structural member
What is the fundamental requirement of structural design?
π πππ’ππππ π π‘πππππ‘β β€ π΄π£πππππππ π π‘πππππ‘β
In ____________________, a member is selected that has cross-sectional properties such as area and moment of inertia that are large enough to prevent the maximum applied axial force, shear, or bending moment from exceeding an allowable, permissible, value
Allowable Strength Design (ASD)
Formula for ASD
π΄ππππ€ππππ ππ‘πππππ‘β
= πππππππ π π‘πππππ‘β / π ππππ‘π¦ ππππ‘ππ
The ________________ will be in the elastic range of the material. This approach to design is also called elastic design or working stress design.
It is utilized when stress are used instead of load or moment.
Allowable Stress Design
_________________ are also
known as service loads.
Working loads
It is based on a consideration of failure conditions rather than working load conditions. A member is selected by using the criterion that the structure will fail at a load substantially higher than the working load
Plastic design
It is similar to plastic design in that strength, or the failure condition, is considered. Load factors are applied to the service loads, and a member is selected that will have enough strength to resist the factored loads. In addition, the theoretical strength of the member is reduced by the application of a resistance factor
Load and resistance factor design (LRFD)
Formula for LRFD
β(πππππ Γ ππππ ππππ‘πππ ) β€ πππ ππ π‘ππππ Γ πππ ππ π‘ππππ ππππ‘ππ
It is used to describe a condition at which a structure or part of a structure ceases to perform its intended function.
Limit State
What are the meaning of this symbols?
π·
πΈ
πΉ
π»
πΏ
πΏπ
π
π
π
π
π· β dead load
πΈ β earthquake load
πΉ β load due to fluids with well-defined pressures and maximum heights
π» β load due to lateral pressure of soil and water in soil
πΏ β live load, except roof live load, including any permitted live load reduction
πΏπ β roof live load, including any permitted live load reduction
π β ponding load
π
β rain load on the undeflected roof
π β Temperature load
π β load due to wind pressure
LRFD (Load and Resistance Factor Design)
Basic Load Combinations
1.4(π· + πΉ)
1.2(π· + πΉ + π) +1.6(πΏ + π») + 0.5(πΏπ ππ π
)
1.2π· + 1.6(πΏπ ππ π
) + (π1πΏ ππ 0.5π)
1.2π· + 1.0π + π1πΏ + 0.5(πΏπ ππ π
)
1.2π· + 1.0πΈ + π1πΏ
0.9π· + 1.0π + 1.6π»
0.9π· + 1.0πΈ + 1.6π»
ASD (Allowable Strength Design) Basic Load Combinations
π· + πΉ
π· + π» + πΉ + (πΏπ ππ π
)
π· + π» + πΉ + 0.75[(πΏ + π + (πΏπ ππ π
)]
π· + π» + πΉ + (0.6π ππ πΈ/1.4)
TRUE OR FALSE
A structural member must not be investigated for various positions of a live load so that a potential failure condition is not overlooked.
False, must be
TRUE OR FALSE
Where structural members are arranged to create continuity, members shall be designed using the loading conditions which would cause maximum shear and bending moments.
True
If a live load is applied quickly and is not removed and reapplied an excessive number of times, the structure can be analyzed as if the load were static. If the load is applied suddenly β¦ the effects of impact must be accounted for.
False, slowly
