8/21/2019 Soil Conditions

http://slidepdf.com/reader/full/soil-conditions 1/13

CLOSE

• BUILDINGS

o BUILDING MATERIALS

o BUILDING TIPS

o FORMWORK/SHUTTERING

o GREEN BUILDINGS

• CONCRETE

o CONCRETE TYPES

GREEN CONCRETE

HIGH STRENGTH CONCRETE

PRECAST CONCRETE

PRESTRESSED CONCRETE

PRESTRESSED CONCRETE DESIGN

LIGHT WEIGHT CONCRETE

HARDENED CONCRETE

READY MIX CONCRETE

FRESH CONCRETE

o CONCRETE ADMIXTURES

o CONCRETE CRACKS

o CONCRETE DURABILITY

o CONCRETE PROPERTIES

8/21/2019 Soil Conditions

http://slidepdf.com/reader/full/soil-conditions 2/13

o FERRO CEMENT

• CONSTRUCTION

o CONSTRUCTION QUALITY

o CONSTRUCTION EQUIPMENTS

o CONSTRUCTION MANAGEMENT

o CONSTRUCTION JOINTS

o CONSTRUCTION PROJECTS

o CONSTRUCTION FACILITIES

o CONSTRUCTION WASTE

o CONSTRUCTION SAFETY

o CONSTRUCTION TIPS

• HOW TO GUIDE

o  ADMIXTURES GUIDE

o MATERIAL TESTING

NON-DESTRUCTIVE TESTS

o DESIGN GUIDE

o MIX DESIGN GUIDE

o HYDRAULICS LAB GUIDE

o QUALITY CONTROL GUIDE

o MATERIAL ESTIMATION

o REINFORCEMENT GUIDE

8/21/2019 Soil Conditions

http://slidepdf.com/reader/full/soil-conditions 3/13

o REPAIR/PROTECTION GUIDE

CRACK REPAIR

o SAFETY GUIDE

• GEOTECHNICAL

o FOUNDATION ENGINEERING

o GE LAB TESTS

o GROUND IMPROVEMENT

o FOUNDATION DESIGN

o GEOTECHNICAL BASICS

• STRUCTURAL

o STEEL DESIGN

o STRUCTURES

o STEEL STRUCTURES

o STRUCTURAL ANALYSIS

o STRUCTURAL DESIGN

• Home

• About Us

• Contact Us

• Privacy Policy

8/21/2019 Soil Conditions

http://slidepdf.com/reader/full/soil-conditions 4/13

• BUILDINGS»

• CONCR!»

• CONS!RUC!ION»

• HO" !O GUID»

• GO!CHNICAL»

• S!RUC!URAL»Home  Geoe!"#$!%& E#'$#ee($#' Fo)#*%$o# E#'$#ee($#'

CO#BIND $OO!ING DSIGN "I!H

%A#PL

The function of a footing or a foundation is to transmit the load form the

structure to the underlying soil. The choice of suitable type of footing depends

on the depth at which the bearing strata lies, the soil condition and the type of

superstructure.

Combined footing

Whenever two or more columns in a straight line are carried on a single spread

footing, it is called a combined footing. Isolated footings for each column are

generally the economical.

Combined footings are provided only when it is absolutely necessary, as

1. When two columns are close together, causing overlap of adjacent

isolated footings

2. Where soil bearing capacity is low, causing overlap of adjacent isolated

footings

. !ro"imity of building line or e"isting building or sewer, adjacent to a

building column.

8/21/2019 Soil Conditions

http://slidepdf.com/reader/full/soil-conditions 5/13

Types of Combined Footing

 

8/21/2019 Soil Conditions

http://slidepdf.com/reader/full/soil-conditions 6/13

• The combined footing may be rectangular, trape#oidal or Tee$shaped in

plan.

• The geometric proportions and shape are so fi"ed that the centeroid of

the footing area coincides with the resultant of the column loads. This results

in uniform pressure below the entire area of footing.

• Trape#oidal footing is provided when one column load is much more than

the other. %s a result, the both projections of footing beyond the faces of the

columns will be restricted.

• &ectangular footing is provided when one of the projections of the footing

is restricted or the width of the footing is restricted.

Rectangular combined footing

• 'ongitudinally, the footing acts as an upward loaded beam spanning

between columns and cantilevering beyond. (sing statics, the shear force

and bending moment diagrams in the longitudinal direction are drawn.)oment is chec*ed at the faces of the column. +hear force is critical at

distance d- from the faces of columns or at the point of contra fle"ure. Two$

way shear is chec*ed under the heavier column.

• The footing is also subjected to transverse bending and this bending is

spread over a transverse strip near the column.

8/21/2019 Soil Conditions

http://slidepdf.com/reader/full/soil-conditions 7/13

 

Design Steps

• 'ocate the point of application of the column loads on the footing.

• !roportion the footing such that the resultant of loads passes through the

center of footing.

8/21/2019 Soil Conditions

http://slidepdf.com/reader/full/soil-conditions 8/13

• Compute the area of footing such that the allowable soil pressure is not

e"ceeded.

• Calculate the shear forces and bending moments at the salient points and

hence draw +/ and 0)/.

• i" the depth of footing from the ma"imum bending moment.

• Calculate the transverse bending moment and design the transverse

section for depth and reinforcement. Chec* for anchorage and shear.

• Chec* the footing for longitudinal shear and hence design the longitudinal

steel

• /esign the reinforcement for the longitudinal moment and place them in

the appropriate positions.

• Chec* the development length for longitudinal steel

• Curtail the longitudinal bars for economy

• /raw and detail the reinforcement

• !repare the bar bending schedule

Detailing

/etailing of steel both longitudinal and transverse in a combined footing is

similar to that of conventional beam$+!$3. /etailing re4uirements of beams

and slabs should be followed as appropriate$+!$3

SEE THE COMPLETE DES!" #TH $" E%$MPLE

•   TAGS

•   FOUNDATION

•   GEOTECHNICAL ENGINEERING

8/21/2019 Soil Conditions

http://slidepdf.com/reader/full/soil-conditions 9/13

Twitter 

 

Facebook 

 

Google +

 

•

•

•

PREVIOUS ARTICLE

PROJECT MANAGER + PROJECT MANAGEMENT NEXT ARTICLE

TYPICAL DAMAGE AND COLLAPSE OF RC BUILDINGS

SI#ILAR AR!ICLS

Se%(!"

8/21/2019 Soil Conditions

http://slidepdf.com/reader/full/soil-conditions 10/13

$AC!ORS A$$C!ING SLC!ION O$ $OUNDA!ION $OR

BUILDINGS

I#PRO&ING BARING CAPACI!' O$ SOIL

PIL $OUNDA!ION SLC!ION BASD ON SOIL CONDI!IONS

8/21/2019 Soil Conditions

http://slidepdf.com/reader/full/soil-conditions 11/13

CAPACI!' O$ PIL GROUP AND $$ICINC'

SUBSCRIB !O UPDA!S

Name:

Email:

SOCIAL

,.,.0F%#1L$2e

345S)61!($6e(17,

430Fo&&o8e(1Fo&&o8

RCO##NDD

LA!S! AR!ICLS

CONCR! RPAIR (UALI!' CON!ROL

8/21/2019 Soil Conditions

http://slidepdf.com/reader/full/soil-conditions 12/13

RPAIR O$ S#ALL AND LARG CRAC)S IN CONCR!

CONS!RUC!ION #A!RIALS #ANAG#N!

$AC!ORS A$$C!ING CONCR! #I% DSIGN S!RNG!H

PLAS!IC SHRIN)AG CRAC)S * I!S PR&N!ION IN CONCR!

LOAD MORE

DO"NLOAD OUR APP

" AR ON $ACBOO)

POPULAR CA!GORIS

Be%m De1$'# 6($*'e e#'$#ee($#' B($*'e1 B)$&*$#' M%e($%&1 B)$&*$#'1 B)$&*$#'Te!"#o&o'9 B)$&*$#' T$:1 Co#!(ee Co#!(ee A*m$;)(e1 Co#!(ee C(%!21 Co#!(ee

D)(%6$&$9 Co#!(ee P(o:e($e1 Co#!(ee Te!"#o&o'9 Co#!(ee

T9:e1 Co#1()!$o# Co#1()!$o# M%#%'eme# Co#1()!$o# P(o<e! C(%!2

Re:%$(  E%("=)%2e E#'$#ee($#' Fo)#*%$o# E#'$#ee($#' GE L%6

Te11 Geoe!"#$!%& E#'$#ee($#' G(ee# B)$&*$#'1 Ho8 ToG)$*e H9*(%)&$!1 L%6 G)$*e M%e($%& Te1$#' G)$*e M$; De1$'# G)$*e No#-De1()!$>e

Te11 P$&e Fo)#*%$o# P(e!%1 Co#!(ee Re$#?o(!eme# G)$*e Re:%$(/P(oe!$o#

8/21/2019 Soil Conditions

http://slidepdf.com/reader/full/soil-conditions 13/13

G)$*e So$& S:e!$%& Co#!(ee See& De1$'# See& S()!)(e1 S()!)(%& A#%&91$1 S()!)(%&

De1$'# S()!)(%& E#'$#ee($#' S()!)(e1 S)(>e9$#' T$:1 T(%#1:o(%$o# W%e(

Re1o)(!e1 Wo(2 P(o!e*)(e1

@ Co:9($'" .,3 - T"e Co#1()!o( 

• Home

•  A6o) U1

• Co#%! U1

• P($>%!9 Po&$!9