Week 3 Challenge

1. 1. State the primary load cases to be considered for design.

• Dead load
• Live load
• Wind load
• Snow load
• Seismic load

2. What is One – Way slab?

One way slab ia=s a slab in which the ratio of longer span to its shorter span is more than or equal to 2 then it is stated as one way slab.

3. What is the value of unit weight of structural steel and soil?

Unit weight of structural steel and soil : 7850kg/cu.m
4. Name few sections that can be defined using Properties tab in STAAD Pro.

• Circular sections
• Rectangular sections
• I-Sections
• T-Sections
• Trapezoidal sections
• Custom Geometric sections

5. Define Primary Beams.

The beams that are directly connected to the columnon the both ends is defined as Primary beams.

2. 1. State the factors and parameters that influence the design pressure intensity of a high-rise building.

2. Mention the load transfer process of a Reinforced Concrete Building.

SLABS

SECONDARY BEAMS

PRIMARY BEAMS

COLUMNS

FOUNDATION

3. 1. Differentiate One-Way and Two way slabs. Elaborate each slab type.

ONE WAY SLAB

• Is supported by beam on two opposite sides only
• Load is carried in one direction perpendicular to the supported beam
• L/B ratio is greater than 2
• Deflected shape is cylindrical
• The quantity of steel is less

TWO WAY SLAB

• Is supported by beam on all sides
• load is carried in all directions
• L/B ratuo is lesser than 2
• deflected shape is saucer like shape
• Quantity of steel is more

2. Explain the concept of secondary beams with proper sketch.

• The secondary beams are provided for the better distribution of slab loads along with the pprimary loads which rests on the thead slabs
• The secondary beams are the beams that are not directly connected to the columns
• secondary beams carry total load and distribute the loads on the respetive manner
• It is important to release the end moments at the supports ,because of this all the secondary beams are provided with the pinned connection.

3. Mention the Primary load cases.
a. State the Indian Standards for each load case

• Dead load (IS 875: Part 1)
• Live load(IS 875: Part 2)
• Wind load(IS 875 : Part 3)
• Snow load(IS 875 : Part 4)
• Earth quake load (IS 1893:2016)
  b. Detail the parameters of each load case
• Member loads
• Concentration loads
• Floor loads
• Plate loads
  c. Brief each load case
• Dead Load

The continuous load in a structure is defined as the load caused by the weight of the members that are permanently attached to the particular structure The dead load is comprised of the load of the column,beam,loads of floor slab,roofing,walls,etc.

• Live load

Loads that are fully or partially vary from time to time on structure

Constant loads throughout the life span of the structure

• Wind load

Is a force on the structure that is arising from the impact of the wind

It is an important load on the structure

• Earthquake load

4. Detail the steps involved in assigning Properties and Support to a model using STAAD Pro sequentially.

ASSIGNING PROPERTIES

• Go to the properties
• Click the define option
• Choose the rectangular or circular properties

ASSIGNING SUPPORT

• Go to the section tab
• Then dialogue box pinned,fixed etc will get appeared
• click on the desired conditions
• Then click OK

5. Brief the steps to be followed to create and assign secondary beams in STAAD Pro

• Create a simple model using STAAD Pro
• Click on create beam option and create a beam in the direction of X znd Z
• Right click on the primary beam
• then add node at the mid on the beam section a node will be added
• Click on the create beamto drew beam along a mid bay

Practical
1. Calculate the wind pressure for the given building
a. Building Dimension : 20m x 30m x 20m height RCC
b. Building usage : Hospital block in city centre
c. Location : Darjeeling

Given

Building Dimension : 20m x 30m x 20m height RCC
Building usage : Hospital block in city centre
Location : Darjeeling

CALCULATE DESIGN WIND SPEEED

vz = Vb . k1 . k2 . k3 . k4

GIVEN DATA FRON IS CODE

Vb = 47 m/s

k1 = 1.07

k2 = 0.8

k3 = 1

k4 = 1

BY CALCULATING

Vb = 40.23 m/s

CALCULATION OF WIND PRESSURE

Pz = 0.9711KN
2. Calculate the Dead load and Live load for the above building with reference to IS standards ( assume suitable sections )

DEAD LOADS DUE TO SLABS

Assuming thickness of 150mm

Dead load due to slabs = 20 . 30 . 25 . 0.15

= 225 KN

Total dead load due to slabs = 5*dead load due to slab

= 5.225