Week 3 Challenge

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

 

DEAD LOAD [IS 875 -PART 1]

LIVE LOAD    [IS 875 -PART 2]

WIND LOAD  [IS 875 -PART 3]

SNOW LOAD  [IS 875 -PART 4]

SEISMIC LOAD [IS 1893 -2016]

    2. What is One – Way slab?

One way slab is a slab which 

longer span ration to shorter 

span ration is grater than  2 .

-One way slab is a plane surface 

of  uniformly loaded which 

deforms into into a cylindrical 

shape ,

hense bending moments devlops in 

one direction . 

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

the value of unit weight of structural steel = 7850 kg/m^3

and soil = 20 

    4. Name few sections that can be defined

using Properties tab in STAAD Pro.

rectangular section 

circular ,   I -section ,  T -section 

tapered -I ,     TRAPEZOIDAL ,

AND custom geometric section .

 

    5. Define Primary Beams.

 

primary beams are beams directly  

connected to column on both ends .

-fuction on this beam is directly transfer 

load to column to foundation .

 

 

2. 1. State the factors and parameters

that influence the design pressure intensity

of a high-rise building.

ANS-

 

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

 

 

 

3. 1. Differentiate One-Way and

Two way slabs. Elaborate each slab type.

 

ONE WAY SLAB -                   TWO WAY SLAB

-THIS beam supported          -supported by beam 

                                              all 4 sides 

by beam on 2 opposite 

sides .

 

-load is carried 1             -   load is carried 

direction perpendicular     both direction .

to support beam .

 

  

-LENGTH /WIDTH       -   length to width 

 greater than equl to       less than 2

2

 

-deflected shape is       -deflected shape is 

is cylindrical.                  saucer like shape .

 

 

    2. Explain the concept of secondary

beams with proper sketch.

ans-

secondary beam primary connected to 

primary beams .

this is a simply supported beams .

-this beams trasfer load to 

primary beams than primary beam 

trasfer load to column to foundation .

-primary beams are rests on  column 

but secondary beams rest or between 

in primary beams .

-secondary beam provided at the 

ends in pinned connection .

 

 

 

 

 

 

 

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

ans-

DEAD LOAD [IS 875 -PART 1]

LIVE LOAD    [IS 875 -PART 2]

WIND LOAD  [IS 875 -PART 3]

SNOW LOAD  [IS 875 -PART 4]

SEISMIC/earthquake LOAD [IS 1893 -2016]

              b. Detail the parameters of each load case

some permament parameters of load cases are given below

-self weight -specify load case where self weight of structure can be defined.

-Standard -Specifies the load case where any load can be defined.

-Creep-Defines a special load case for specific calculation.

Prestress-This type is used for calculations of prestressed structures.

 

              c. Brief each load case

 

1.dead load  -

it is a self weight of 

whole structure .

almost dead load cover 50 to 60% 

of total load .

 

 

2.live load  -

Live load is the second major load on building

 From its name we can easily understand that

the live load is a load of live things,

such as humans loads, animals load and etc.

Live load should be taken from IS : 875 part 2

in which live load is changed as per

type of building and its uses.

 

3. Wind load

Tall buildings is mostly affected by wind load.

Wind load is a type of horizontal load that is

acting on a various faces of building.

Wind load is depends on a wind

intensity which is keep changing as per location.

IS:875 part 3 is provide the various codal provision of wind load.

4. Snow load

Snow load is also become a more

important in some cool places such as

jammu & kashmir, himalay, uttrakhand and other locations.

Is 875 part 4 includes the all calculation

provision of snow load on building.

5.earthquake  load

A horizontal load is acting on a building during time of earthquake.

Earthquake load is like a sudden Impact load

on building due to movement or vibration of surrounding earth.

Earthquakes load become most dangerous

for building due to its sudden Impact with

high Intensity at leas time. But nowadays,

building is designed to resist earthquake load.

Building is designed accordingly IS 1893-2016

which includes the all details of seismic

calculation and consideration on building.

 

 4. Detail the steps involved in assigning Properties

and Support to a model using STAAD Pro sequentially.

 

ans-steps involved in assigning Properties

 

-open staad pro 

-goto properties 

-open a dialouge box 

click  define option .

-next dialouge box will be 

open ,

-there diffrent types section 

are avilable like  circle , reactangle ,  trapezoidal  and t section .

-chosse any one section give dimesion and add on it 

and assign to view  than okay .

 

 ASSIGNING Support -

-Go to support 

-open a dialouge box > go to creat > diffrent 

types of support open like fixed , fixed but ,pinned  etc.

-click on desired support > click on add 

-than go to assign on view . ok

    5. Brief the steps to be followed to create

and assign secondary beams in STAAD Pro

 

ans-

-creat new analytical  model on metric unit 

-geometry tab  creat diffrent nodes in 

diffrent  x , y , z direction .

-add the beams .

-next goto properties provide reactangle section 

-next creat material 

-next support and assign in view 

-next creat secondary beam in here 

we select a beam than go to right click on 

mouse and goto  insert node in beam than next click on

add mid point > ok 

 

-add beam > perpendicular intersection 

in this way we able to creat a secondary beam

 

 

 

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

 

steps -

1.calculate design wind speed -

 

Vz =Vb . K1 .K2 .K3 .K4

 

K1= RISK COFFICIENT TAKE values  is 875  part 3  

2015 -table 1 

 

k2 =terrain  roughness and height factor 

k3= topography factor  is code 875 :  part 3 2015 clause 6.3.3 

k4 =importance factor .

 

 

acc. to IS CODE -

 

Vb =47m/s

 

k1= 1.07

k2=.8

k3=1

k4=1

 

 

calculation put values in above formula 

 

Vz =Vb .K 1.K2  K3. K4

 

Vz=47 x1.07 x0.8 x1x1

 

  =40.23 m/s

 

wind pressure -

 

Pz = 0.6 Vz ^2

 

  =0.6 x [40.23]^2

 

  =971.07 N

  =.97107 KN 

 

SIMILARLY calculate diffrent height 

 

 

2. Calculate the Dead load and Live load for

the above building with reference to IS

standards ( assume suitable sections )

 

ans-

 

D.L . DUE TO SLAB -

 

assuming slab thickness = 150 mm

 

dead  load due to slab =  L X B XH X SLAB THICKNESS 

 

                                     =20 X30 X25 0.15 

  

                                       =225 KN .

 

 

 

IN This project total  5 floor slab 

 

so total  dead  load due to slab

 

             = 5 x225 = 1125 KN .

 

 

DEAD LOAD DUE TO BEAMS -

 

Assume beam cross section 

350 x450 mm 

 

-dead L. due to beams = size of beam  x height 

                                       =350 x450 mm  x0.25

 

                                       =3.94  KN /M  Take it  4 kn /m 

 

 

super imposed load due to partition wall -

 assume 150 mm thickness brickwork 

 

height of brick work = floor ht.- depth of beam 

 

                                  3.75 -.45  =3.3 m 

 

total dead load =3.3  x.15 x .18  = 8.91 KN/M .

 

 

 

--LIVE LOAD 

USE CODE  IS 875 -PART 2 

GIVE LIVE LOADS VALUES FOR 

DIFFRENT ROOMS  

 in here hospital building  so 

acc . to code 

 

OCCUPANCY                         LIVE LOAD [KN/M^2]

 

-For ward room

dressing rooms                        2

dormitries and lounges .

                                          

-kitchen and lab                      3

 

-dining rooms ,cafeteria         3

 

-toilets and bathrooms          2

 

-x -ray  and operating 

rooms                                   3

 

-office and opd rooms         2.5

 

-corridoor and passage        4