Help i hav no idea how to work out the design load

In summary, to determine the design load for a reinforced concrete office building, you need to use an appropriate load combination, which in this case is 1.2G+1.5Q. The dead load (G) includes the weight of the building, floor finishes, and partitions, while the live load (Q) includes temporary loads such as people and furniture. By plugging in the values for G and Q into the load combination equation, you can calculate the design load, which in this case is 33.4 kNm.
  • #1
beezz
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help i hav no idea how to work out the design load!

Homework Statement


A typical floor layout of a reinforced concrete office building is shown in Figure 5. The
reinforced concrete floor supports a permanent dead load G (ceiling services, floor finish and
partitions, but not self-weight) of I.OkPa and superimposed live load Q of 3.0kPa. The slab
thickness is I60mm and beams are 450mm deep and 300mm wide as shown in Section A-A
in Figure 5. The concrete characteristic compressive strength (f"c) is 32MPa and steel yield
strength (fsy) is 500 MPa. For the beams, the cover to the ligatures is 30mm.

Homework Equations


(a) Determine the design load in kN/m based on the given loads and using an appropriate
load combination;
(b) Find the maximum design negative and positive moments along the beam using the
simplified method;
(c) Find the maximum shear forces along the beam;
(d) Design the flexural reinforcement required to satisfy the maximum negative and positive
design moments as calculated in part (b). Use N20 bars for the flexural reinforcement
(curtailment details of reinforcement is not required);
(e) Design the shear reinforcement to resist the maximum design shear force. Use NI2 for
shear ligatures.

The Attempt at a Solution


i atempted it and hav looked at the solution but can't seem to work out my dead loads
heres the solution for part A

w*= 1.2G+1.5Q = 1.2(11.5 _2.1+3) + 1.5 *9 = 33.4 kNm
 

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  • #2


To determine the design load, you need to first understand the concept of load combinations. In structural design, loads are typically classified into two categories: dead loads and live loads. Dead loads are the permanent loads that are always present on a structure, such as the weight of the building itself, the floor finishes, and partitions. Live loads, on the other hand, are the temporary loads that can vary in magnitude, such as people, furniture, and equipment.

In order to determine the design load, you need to use an appropriate load combination, which is a combination of different loads that considers their different effects on the structure. In this case, you are given the values for the dead load and live load, and you need to use the load combination 1.2G+1.5Q, where G represents the dead load and Q represents the live load.

To find the design load, you need to plug in the values for G and Q into the load combination equation:

w*= 1.2G+1.5Q

= 1.2(11.5 _2.1+3) + 1.5 *9

= 1.2(9.4) + 13.5

= 33.4 kNm

Therefore, the design load for this structure is 33.4 kNm.
 
  • #3


To work out the design load, you need to use the load combination equation provided in part (a). The equation is:
w* = 1.2G + 1.5Q
Where:
w* = design load
G = permanent dead load
Q = superimposed live load

In this case, G is given as 1.0 kPa and Q is given as 3.0 kPa. Plugging these values into the equation, we get:
w* = 1.2(1.0) + 1.5(3.0)
w* = 1.2 + 4.5
w* = 5.7 kPa

This is the design load in kN/m for the given floor layout.
 

1. What is a design load?

A design load refers to the maximum amount of weight or force that a structure or object is expected to support or withstand. It is an important factor in the design and construction of buildings, bridges, and other structures to ensure their safety and stability.

2. How do you calculate the design load?

The design load is typically calculated by considering factors such as the weight of the structure or object, the expected use and occupancy, and the environmental conditions it will be exposed to. This calculation is usually done by engineers or architects using mathematical equations and building codes.

3. What are the different types of design loads?

There are several types of design loads, including dead loads, live loads, wind loads, snow loads, and seismic loads. Dead loads refer to the weight of the structure itself, while live loads refer to the weight of people, furniture, and other movable objects. Wind loads, snow loads, and seismic loads are specific to the environmental conditions and geographic location of the structure.

4. How do design loads affect the structural integrity of a building?

Design loads are crucial in determining the strength and stability of a building. If the design load is too low, the structure may not be able to support the weight and forces it is subjected to, which can lead to collapse or failure. On the other hand, if the design load is too high, it can result in overbuilding and unnecessary construction costs.

5. What happens if the design load is exceeded?

If the design load is exceeded, it can cause structural damage or failure, potentially putting the safety of the building's occupants at risk. It is important for engineers and architects to accurately calculate and account for all potential design loads to ensure the structural integrity of a building.

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