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Result Summary                  
Anchor Rod Embedment, Spacing and Edge Distance       Warn  
Overall         ratio = Infinity NG  
Seismic Design         Tension =   NA  
          Shear =   NA  

Design Code Reference                  
Anchor bolt design based on                 Code Abbreviation
ACI 318-14 Building Code Requirements for Structural Concrete and Commentary ACI 318-14
PIP STE03350 Vertical Vessel Foundation Design Guide-2008 PIP STE03350
PIP STE05121 Anchor Bolt Design Guide-2006 PIP STE05121
ASCE Anchorage Design for Petrochemical Facilities-2013 ASCE Anchorage
                Code Reference
Design Option          
Select anchor bolt design code          
Select design using or not using anchor reinforcement      
Concrete Mat or Pedestal Input          
Dp=159.36 Sp=66.01 Dbc=144.00 c1=7.68 c2=19.29 c4=19.29 ANC
Select concrete mat shape   =        
Octagon mat face-to-face distance Dp = [in]          
No of anchor bolt Nab =        
Anchor bolt bolt circle diameter Dbc = [in]          
Anchor Bolt Forces Input                    
Anchor bolt loads input by   =
Factored moment at base of vessel Mu = [kip-ft]            
Factored shear at base of vessel Vu = [kips]            
Empty vessel weight De = [kips]          
Anchor Bolt Data Input              
Concrete strength f'c = [ksi]    
Anchor bolt material   =          
Anchor tensile strength futa = 58.0 [ksi]         ACI 318-14
      Anchor is ductile steel element       2.3 & 17.3.3 (a)
Anchor bolt diameter da  = [in]            
Anchor bolt has sleeve   =            
Anchor bolt head type   =        
Anchor effective cross section area Ase = 0.000 [in2]        
Anchor bolt head bearing area Abrg = [in2] Error:
For anchor bolt da >1.5 inch, many head types are not
commercially available.
User can select Heavy Hex or Custom Head head type.
Anchor bolt 1/8" (3mm) corrosion allowance =            
                PIP STE05121
Anchor bolt embedment depth hef = [in] 18.00   Warn   Page A -1 Table 1
Pedestal height ha = [in] 17.50   OK    
Supplementary reinforcement                 ACI 318-14
        For tension   = Condition B       17.3.3 (c)
        For shear Yc,v = Condition A
Concrete cracking   =,,
Provide built-up grout pad ?   = 
Seismic Input                 ACI 318-14
Seismic design category SDC >= C   = 

Design Basis and Assumptions  
The design of circular pattern anchor bolt group uses the Method 2 Sawcut with hef’ and Neutral Axis at Center as stated in the following references
1. ASCE Anchorage Design for Petrochemical Facilities - 2013    Example 2 Step 5(c) on Page 145
2. ASCE 2010 Structural Congress - Concrete Breakout Strength in Tension for Vertical Vessel Anchorage in Octagon Pedestals
The design of circular pattern anchor bolt group is simplified as design of a single anchor bolt with 3 side free edges sawcut at midway between adjacent anchors. The simplified design method uses the following assumptions
1. The moment is resisted only by the anchor bolt group and it does not take into account the contribution of concrete compression
    force against base plate in the moment equilibrium
2. The neutral axis is not shifted and is located at center of vessel
3. It does not consider strain compatibility between the concrete and steel elements which comprise the anchorage.
4. In the assumed 3 side free edges sawcut model, when anchor is located less than 1.5hef from three or more edges, the reduced
    hef' is used to calculate concrete projected failure area ANC
The utilization ratio of simplified method used in this calculation is conservative compared to the accurate but more complex approach. The detail comparison and analysis of this simplified method is addressed in reference 2 above.

CONCLUSION                 View Detail Calc
Anchor Rod Embedment, Spacing and Edge Distance       Warn  
Overall ratio = Infinity NG  
Anchor Rod Tensile Resistance ratio = Infinity NG  
Concrete Tensile Breakout Resistance ratio = 0.73 OK  
Anchor Pullout Resistance ratio = 2.00 NG  
Side Blowout Resistance ratio = 2.00 NG  
Anchor Rod Shear Resistance ratio = NaN NG  
Concrete Shear Breakout Resistance - Perpendicular To Edge ratio = 0.00 OK  
Concrete Shear Breakout Resistance - Parallel To Edge ratio = 0.00 OK  
Concrete Pryout Shear Resistance ratio = 0.00 OK  
Tension Shear Interaction          
Tension Shear Interaction ratio = 2.00 NG  
Seismic Design         ACI 318-14
Tension Not Applicable       NA
Seismic SDC< C or E<=0.2U , additional seismic requirements in is NOT required, as per &    
Shear Not Applicable       NA
Seismic SDC< C or E<=0.2U , additional seismic requirements in is NOT required, as per &    


Single Anchor Bolt Tensile and Shear Load       PIP STE03350
Factored compression at top of concrete pedestal Pu  = Mu /0.667 Dbc + 0.9 De /2 = 210.10 [kips] Section 4.6.2 Eq 5
Factored frictional resistance f Vf =  f m Pu = 0.75 x 0.55 x Pu    = 86.67 [kips] Section 4.6.2 Eq 6
    >  Vu  shear load taken by the friction Section 4.6.2 Eq 7
Factored single bolt tensile load  Nua = 4 Mu / (Nab x Dbc) - 0.9 De / Nab = 29.54 [kips] Section 4.6.1 Eq 4
Factored single bolt shear load  Vua = shear load taken by the friction = 0.00 [kips]    
Single Anchor Bolt Edge Distances and Projected Failure Area        
Anchor bolt edge distance c1 = (Dp - Dbc) / 2 = 7.68 [in]  
  c3 = Dp - c1 = 151.68 [in]  
  c2 = = 19.29 [in]  
  c4 = c2     = 19.29 [in] ACI 318-14
Effective embedment depth hef' =   = 12.86 [in]
Octagon side edge length Sp = Dp / (1+√2) = 66.01 [in]  
Octagon shape conc mat area Ap =   = 21038 [in2]  
Projected conc failure area ANC = = 1026 [in2]