Week 3 Challenge
Answer of Question No. 1
1.1 State the primary load cases to be considered for design.
Answer:
The Primary Load Cases that are to be considered for design are listed below
- Dead Load - This Load We leran from IS 875:Part-1
- Live Load - This Load We leran from IS 875:Part-2
- Wind Load - This Load We leran from IS 875:Part-3
- Snow Load - This Load We leran from IS 875:Part-4
- Seismic Load - This Load We leran from IS 1893:2016
2. What is One – Way slab?
Answer:
One Way Slab:
One way slab is a in which the ratio of the longer span to its shorter span is more than or equale to 2.
One Way slab load distribution takes place along its shorter span. Hence bending also happens at the shorter of the slab.
One Way slab is a plane surface of uniformly loaded which deforms into a cylindrical shape and hence the bending moment develops only in one direction , These type of slab is called one way slab.
3. What is the value of unit weight of structural steel and soil?
Answer:
The unit Weight of structural Steel and Soil is 7859kg/cu.m and 1500kg/cu.m respectively
4. Name few sections that can be defined using Properties tab in STAAD Pro.
Answer:
Some Sections that can be defined using properties tab in STAAD Pro are listed...
- Circular sections
- Rectangular sections
- I-Sections
- T-section
- Tappered-I-section
- Trapezoidal sections.
- Custom Geometric Sections.
5. Define Primary Beams.
Answer:
- The prmary beams are the beams that are directly connected with the column on both the ends.
- The function of the primary beams are to transfer the load of the slab directly to the column that they are resting on.
Answer of Question No. 2
2. Mention the load transfer process of a Reinforced Concrete Building
Answer:
The Load transfer procedure of a reinforced concrete building has been illustrated below in the form of the flow chart.
Answer of Question No. 3
3.1. Differentiate One-Way and Two way slabs. Elaborate each slab types
Answer:
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3.2. Explain the concept of secondary beams with proper sketch.
Answer:
The secondary beams are provided for better distribution of slab loads along the primary beams which rests on the slab
So mainly the secondary beams are the beams that are not directly connected to the column the secondary beams rest on the other beams that are directly rest on the
3. Mention the Primary load cases.
a. State the Indian Standards for each load case
b. Detail the parameters of each load case
c. Brief each load case
Answer:
a. State the Indian Standards for each load case
- Dead Load - This Load We leran from IS 875:Part-1
- Live Load - This Load We leran from IS 875:Part-2
- Wind Load - This Load We leran from IS 875:Part-3
- Snow Load - This Load We leran from IS 875:Part-4
- Seismic Load - This Load We leran from IS 1893:2016
b. Detail the parameters of each load case
- Member Loads
- Concentration Loads
- Floor loads.
- Plate Loads.
The dead load is definned as the continuous load in a structure i.e the load of machine etc and this load caused by the weight of he members that are permanently attached to the particular structure.
The dead load of the structure comprised of the load column, load of the column, load of the beam, loads of the floor slab roof walls the load of the of the window or may be the load of the electrical fixture. All the loads which is permanent on the structure is called as the dead load of the strucutre.
Some of the Dead load (Unit Weight) of the following materials:
- Cement: 1440 kg/cu.m
- Steel : 7850kg/cu.m
- sand :2400kg/cu.m
- Concrete :2400kg/cu.m
- RCC: 2500Kg/Cu.m
- Soil: 1800kg/cu.m
Live Load: Live load are the loads that are fully or partially vary from time to time on the structure.
- Live loads are not constant loads throught of the life span of a structure.
- live load may vary tme to time according to its usage or the occupancy
- For residencial buildinguse 3KN/sqm
- All rooms and kichen2 kn.sqm
- Bathroom and toilet 2kn/sqm
- Balcony 3 kn/cum
- Staircase/ Corridor 3:kn/cum
Wind Load: Wind load is a forc on a surface that is arising from the impact of the wind. wind load is an important load case for the structure . we considered this tpe of load where the structure are situated or located in the hilly areas of rthe mountain areas where we can expect high speed of the winds that can affect the structure.
Earthquake load
Earthquake load are seismic loads are also an important load case that needs to be considered while designing and analysis of the high rise structure of the building
Mainly we considered this type of loads where there are high chance ofEarthquake or we can say we have to consider this load in the earthquake prone areas. where there is a high and low
4. Detail the steps involved in assigning Properties and Support to a model using STAAD Pro sequentially.
Answer:
Steps that are involved in assigning the properties and support to a model using the STAAD Pro software have been discussed below.
The first step in order to assigning the properties to amodel in a model using STAAD Pro software, go to the Properties tab and then there will be a dialog box and in that dialogue box there is an option called Define menu just click on that option.
After choosing the section properties specify the dimensions in that dialouge box.
And now assign the property to the model or strucutre and to assign the perorty selects the section that we have just created from the create section and click on the option assign to the selected view and then click on the assign option and then assign the property and done.
Assigning Suppport:
In order to Assign the support to the model using STAAd Pro Software, go to the section tab and then there will be another dialogue box and in that dialogue box there will be an option called create New just click on that option
After clicking on that option there will be another dialogue box and in that dialogue
And Now Assign the support to the model or structure and to assign hte support select the support that we have just created from the created section and click on the option Assign to the selected view and click on the assign option and then assign the property and done.
5. Brief the steps to be followed to create and assign secondary beams in STAAD Pro
Answer:
- First create New model by using the node in STAAD Pro \
- Click on the create beam option and crete a beam in the direction of X and Z axix
- Right click on the primary beam in the section
- Right click and add node at the mid beam section a node will be Added
- Click on the create beam todraw beam along mid of the bay.
Procedure:
Given:
Building dimensions L 20*30*20
BUoilding usage : Hospital
Location of the building: Darjeeling
Step-1
Calculation of Design Wind Speed:-
We know the formula to calcuate the design
Vz=Vb⋅k1⋅k2⋅k3⋅k4
now
We can find the value of risk co-efficient,
We can find the value of topography factor from IS cide 875:Part 3 2015 clause no 6.3.3.
Given Data form the IS code:
CALCULATION:
STEP 2: Calculation of Wind pressure:
2. Calculate the Dead load and Live load for the above building with reference to IS standards ( assume suitable sections)
Dead Load due to Slabs:
- Assuming the slab thickness of 150mm.
- Dead Load due to the Slabs = Length * Breadth * Height * Slab Thickness.
- Dead Load due to the Slabs
= 20 ⋅ 30 ⋅ 25 ⋅ 0.15 - Dead Load due to the Slabs
= 225 K N - In this project we have total of five floor slabs,therefore:
- Total dead load due to all the slabs = 5 * Dead Load due to the Slabs.
- Total dead load due to all the slabs
= 5 ⋅ 225
Total dead load due to all the slabs = 1125 KN.
Dead Load due to the beams:
- Assume the beams of cross-section 350*450mm.
- Dead load due to the beams = Size of the beam * Height.
- Dead load due to the beams
= 0.35 ⋅ 0.45 ⋅ 25 - Dead load due to the beams
= 3.94 K N m
Dead load due to the beams
Superimposed Loads due to the Partition walls:
- Assuming 150mm thickness of brickwork.
- Height of brickwork = Floor height - depth of the beam.
- Height of the brickwork
= 3.75 - 0.45 - Height of brickwork
= 3.3 m - Therefore,the dead load due to the brick masonary partition
= 3.3 ⋅ 0.15 ⋅ 18
The Dead Load due to the brick masonary partition = 8.91 KN/m.
Live Load:
- We can calculate the live load of a given structure by using the IS 875:Part 2,which states different live loads values for different rooms.
- As our building is the Hospital building,the all the proposed live load values for hospital building according to the IS 875:Part 3 has been listed below:
| OCCUPANCY |
LIVE LOAD |
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For ward rooms,dressing rooms,dormitories and lounges |
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