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BASE PLATE DESIGN          

Result Summary                  
Overall         ratio = 0.74 OK  

Design Code Reference                  
Base plate design based on                 Code Abbreviation
AISC Design Guide 1: Base Plate and Anchor Rod Design 2nd Edition AISC Design Guide 1
ACI 318-11 Building Code Requirements for Structural Concrete and Commentary ACI 318-11
                Code Reference
Base Plate Data                    
Column section type   =        
Column section size   =          
Column section properties d = 12.100 [in] tf = 0.605 [in]    
  bf = 12.000 [in] tw = 0.390 [in]    
Base plate anchor bolt pattern   =          
Base plate anchor bolt pattern   =      
               
 
                     
                   
Base plate width B = [in] 20.00 in          
Base plate depth N = [in] 20.00 in          
Base plate thickness tp = [in] 1.75 in          
Anchor bolt spacing C C = [in] 16.00 in          
Anchor bolt spacing D D = [in] 16.00 in          
Concrete pedestal width bc = [in]          
Concrete pedestal depth dc = [in]          
                     
Anchor bolt material   =          
Anchor tensile strength futa = 58.0 [ksi]          
Anchor bolt diameter da  = [in] max dia=1.50 in          
Anchor effective cross section area Ase = 0.969 [in2]        
Anchor bolt 1/8" (3mm) corrosion allowance =            
Total no of anchor bolt in base plate n =              
No of bolt along outermost bolt line nt =              
                     
Concrete strength fc' = [ksi]            
Base plate yield strength Fy = [ksi]            
                     
Factored column load                    
  Load Cases Pu or Tu   [kips] Mu   [kip-ft]
  LC1 Axial Compression Pu =  
  LC2 Axial Compression +
Moment
Pu = Mu =
  LC3 Axial Compression +
Moment
Pu = Mu =
  LC4 Axial Tensile Tu =  
   
                     
Suggested plate thickness for rigidity:
tp = max. of m/4  and  n/4
=              
                     
   
                     
                   
Strength reduction factors                 ACI 318-11
Bearing on concrete fc = 0.65           9.3.2.4
Base plate bending fb = 0.90            

CONCLUSION
                 
Overall ratio = 0.74 OK  
LC1: Axial Compression          
Suggested Min Plate Thickness for Rigidity ratio = 0.74 OK  
Pedestal Concrete Base Bearing Strength ratio = 0.06 OK  
Base Plate Required Min Plan Size B x N ratio = 0.00 OK  
Base Plate Required Min Thickness ratio = 0.37 OK  
LC2: Axial Compression + Moment          
Base Plate B x N or Anchor Bolt C x D Dimension Check ratio = 0.00 OK  
Base Plate Required Min Thickness ratio = 0.70 OK  
LC3: Axial Compression + Moment          
Base Plate B x N or Anchor Bolt C x D Dimension Check ratio = 0.00 OK  
Base Plate Required Min Thickness ratio = 0.43 OK  
LC4: Axial Tension          
Anchor Rod Tensile Resistance ratio = 0.15 OK  
Base Plate B x N or Anchor Bolt C x D Dimension Check ratio = 0.00 OK  
Base Plate Required Min Thickness - Bending to Flange/Web ratio = 0.35 OK  

CACULATION                 AISC Design Guide 1
W Shape m = ( N - 0.95 d ) / 2 = 4.253 [in] 3.1.2 on Page 15
  n = ( B - 0.8 bf ) / 2 = 5.200 [in]  
                   
Suggested min. plate thickness for rigidity: tp = max. of m/4 and n/4 = 1.300 [in]  
  ratio = 0.74 < tp OK  
                   
LC1: Axial Compression                
Concrete Base Bearing Strength                
Factored compression force Pu =       = 100.00 [kips]  
Base plate area A1 = B x N   = 400.00 [in2]  
Pedestal area A2 = bc x dc   = 900.00 [in2]  
                  ACI 318-11
  k = min [ sqrt(A2/A1), 2 ] = 1.500   10.14.1
  fc Pn = fc 0.85 fc' A1 k = 1723.80 [kips] 10.14.1
  ratio = 0.06 > Pu OK  
               
Base Plate Required Thickness             AISC Design Guide 1
  X = = 0.058   3.1.2 on Page 16
  l = = 0.244    
  l n' = l sqrt( d x bf ) / 4 = 0.736 [in]  
  L = max (m, n, l n' ) = 5.200 [in] 3.1.2 on Page 15
Base plate required thickness tmin = = 0.646 [in]  
Base plate plan size B x N is adequate. ratio = 0.37 < tp OK  
               
LC2: Axial Compression + Moment        
  Pu = 75.00 [kips] Mu = 50.00 [kip-ft]  
  e = Mu / Pu = 8.00 [in]  
  fp(max) = fc 0.85 fc' k = 4.31 [ksi]  
  qmax = fp(max) x B = 86.19 [kips/in]  
  ecrit = N/2 - Pu / (2qmax) = 9.56 [in]  
e < ecrit small moment case applied
               
Small Moment Case              
Bearing length Y = N - 2e = 4.000 [in]  
Verify linear bearing pressure q = Pu / Y = 18.75 [kips/in]  
        < qmax OK  
  fp = Pu / BY = 0.94 [ksi]  
  m = max(m , n) = 5.200 [in]  
              AISC Design Guide 1
Y < m tmin = = 1.218 [in] Eq. 3.3.15a-1
Base plate plan size B x N is adequate. ratio = 0.70 < tp OK  
               
               
LC3: Axial Compression + Moment        
  Pu = 45.00 [kips] Mu = 25.00 [kip-ft]  
  e = Mu / Pu = 6.67 [in]  
  fp(max) = fc 0.85 fc' k = 4.31 [ksi]  
  qmax = fp(max) x B = 86.19 [kips/in]  
  ecrit = N/2 - Pu / (2qmax) = 9.74 [in]  
e < ecrit small moment case applied
               
Small Moment Case              
Bearing length Y = N - 2e = 6.667 [in]  
Verify linear bearing pressure q = Pu / Y = 6.75 [kips/in]  
        < qmax OK  
  fp = Pu / BY = 0.34 [ksi]  
  m = max(m , n) = 5.200 [in]  
              AISC Design Guide 1
Y >= m tmin = 1.49 m sqrt( fp / Fy) = 0.750 [in] Eq. 3.3.14a-1
Base plate plan size B x N is adequate. ratio = 0.43 < tp OK  
               
               
LC4: Axial Tension                
Factored tensile force Tu =       = 25.00 [kips]  
                   
Anchor Rod Tensile Resistance                 ACI 318-11
Anchor rod tensile resistance Tr = f t,s n Ase futa = 168.61 [kips] D.5.1.2 (D-2)
  f t,s = 0.75 for ductile steel element       D.4.3 (a)
  ratio = 0.15 > Tu OK  
                   
Bolt pattern Bolt Both Outside and Inside Flange      
Total No of anchor bolt n =       = 4.0    
Bolt to column center distance f =       = 8.00 [in]    
Bolt to column web center distance f1 =       = 8.00 [in]    
Factored tensile force in single bolt Tb = Tu / n = 6.25 [kips]  
                   
 
                   
Bending to Column Flange                 AISC Design Guide 1
Moment lever arm a = f - 0.5 d + 0.5 tf = 2.25 [in] Eq 3.4.6  on Page 26
Moment to column flange Mu = Tb x a = 1.17 [kip-ft]  
Effective plate width beff = 2 x a = 4.51 [in] Sect 3.2 3 on Page 18
                   
Base plate required thickness tp1 = = 0.621 [in] Eq 3.3.13a  on Page 25
                   
Bending to Column Web                 AISC Design Guide 1
Moment lever arm a = f1 - 0.5 tw = 7.81 [in] Example 4.5 on Page 34
Moment to column web Mu = Tb x a = 4.07 [kip-ft]  
Effective plate width beff = 2 x a = 15.61 [in] Example 4.5 on Page 35
                   
Base plate required thickness tp2 = = 0.621 [in] Example 4.5 on Page 35
  tmin = max ( tp1, tp2 ) = 0.621 [in]  
Base plate plan size B x N is adequate. ratio = 0.35 < tp OK  
                   

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