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CFVR1313 - Bending + Axial force design according to ACI 318

Design a reinforced concrete beam subjected to Bending + Axial force according to ACI 318

A fixed beam which has a circular reinforced concrete section is subjected to an axial compression force of 236 kips and a bending moment of 179 ft-kips.
The aim of the example is to obtain the necessary steel amount according to ACI 318.

Element types used in the model: BEAM4

Needed CivilFEM Modules:
Geotechnical Module
Bridges and Civil Non Linearities Module
Advanced Prestressed Concrete Module

The example can be launched on an educational license.
KEYWORDS
Beam
Cross Section
Code Checking/Design
Reinforced Concrete
ACI 318

Model Statistics
Number of elements 4
Number of nodes 5
Number of civil materials 2
Number of cross sections 1
Number of shell vertices 0

Log file: CFVR1313.DAT


   FINISH
  ~CFCLEAR,,1
   NomFile='CFVR1313'
 /TITLE,%NomFile%, BENDING + AXIAL FORCE DESIGN ACCORDING TO ACI 318

! -------------------------------------------------------------------------------------
! Initial data
! -------------------------------------------------------------------------------------
! CivilFEM SETUP
 ~UNITS,BIN    !in,sg,Pound force
 ~CODESEL,,ACI

 ! Parameters
  Ec_ACI=4566000				! psi
  
! Preprocessor
  /PREP7

! Material Definition
 ~CFMP,1,LIB,CONCRETE,ACI,fc_5000
~CFMP,1,USER
~CFMP,1,DatGen  ,Gxy     ,,1902000  
~CFMP,1,DatGen  ,RHO     ,,2.33931e-004 
~CFMP,1,ACI_C   ,Ec      ,,Ec_ACI,7,0,0

 ~CFMP,2,LIB,REINF,ACI,fy_60000

! Element Type Definition
  ET,1,Beam4                            ! Element Type 1: 3D Beam

! Cross-section definition
 ~CSECDMS,1,CIRC,1,20
! Reinforcement definition
 ~RNFDEF,1,1,2,1,0,2,1       ! Total Reinf.area=1 in^2
							! Geometric cover=2 in

							! Beam & Shell property
 ~BMSHPRO,1,BEAM,1,1,,,4,1,0,,Beam property

! Model Construction
  N,1                                   ! Nodes input
  N,5,200
  FILL,1,5

  E,1,2                                 ! Elements input
  EGEN,4,1,1,1

  D,1,ALL                     ! Constraint conditions

/SOLU
  M=3312000           ! 276 ft-kips vertical lumped force
  H=-214000           ! 214 kips axial force
  F,5,FX,H
  F,5,MZ,M
  SOLVE               ! Calculation

/POST1

! Postprocessor
  ~CFSET,,1,1       ! Read first load step

! Bending + Axial design for T sections according to ACI
  ~DIMCON,2DB,,,5,10

!--------------------------------------------------------------------------------------
! DATA CHECK
!--------------------------------------------------------------------------------------
! Data comparison number
  NComp = 2
  NComp_ch = 0

! Matrix dim.
  *DIM,LABEL,CHAR,Ncomp,1
  *DIM,LABEL_CH,CHAR,Ncomp_ch,1
  *DIM,VALUE,,Ncomp,3
  *DIM,VALUE_CH,CHAR,Ncomp_ch,3
  *DIM,TOLER,,Ncomp,2

! Labels
  LABEL(1,1) = 'CRTC2D_I'
  LABEL(2,1) = 'CRTC2D_J'

! Correct values
  VALUE(1,1)=1.00
  VALUE(2,1)=7.394

! Comparison
 ~PLLSCON,CRT_TOT
 *GET,VALUE(1,2),ELEM,4,ETAB,CFETAB_I
 ~PLLSCON,REINFACT
 *GET,VALUE(2,2),ELEM,4,ETAB,CFETAB_J

! Warning and error tolerances
  TOLER( 1, 1)= 3E-02 $ TOLER( 1, 2)= 5E-02
  TOLER( 2, 1)= 4E-01 $ TOLER( 2, 2)= 4E-01

!--------------------------------------------------------------------------------------
! Results comparison
!--------------------------------------------------------------------------------------
  COMPARA.MAC

Results

LabelTargetCivilFEMRatioTolerance
CRTC2D_I 1 0.999971.000 0.05
CRTC2D_J 7.394 7.75880.951 0.4


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