BS 1377 Part 8 1990          
Triaxial Saturation
Location Job Ref:
BH No.
Soil Description Sample No.
Depth
Test method  BS1377: Part 8:  1990 Clauses 5.3/5.4* Date
  
   
Consolidated-undrained/consolidated-drained*triaxial compression test        
With/without*side drains     Date started     Completed    
Pressure system no.       Cell no.              
Required effective pressure s3 kPa     Initial diameter Do mm    
Cell pressure   s3 kPa     Initial length Lo mm    
Back pressure   ub kPa     Initial area Ao mm2    
Pore pressure after build-up ui kPa     Initial volume Vo cm3    
Excess pore pressure   (ui - ub) kPa                
   Consolidation data
Date   Time Elapsed time /t Volume change   Pore pressure      
      t(min)     indicator              
            Reading Difference Reading Difference Dissipation
                  u (ui - u)   U  
            mL mL     kPa   %  
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
                           
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Final difference =
total consolidation volume change DVc
After consolidated                      
Consolidated volume Vc = Vo - DVc   cm3     Coeffiecient of volume    
Volumetric strain ev =  DVc     Compressibility  
  Vo     mvi = 1000ev  
Consolidated length Lc = Lo(1 - 1/3 ev) mm       (ui - uc)  
Consolidated area Ac = Ao(1 - 2/3 ev) mm2     mvi =     m2/MN  
Value of l     Value of F       Coeffiecient of      
From graph / t100   t 100 =      min Consolidation    
   
Significant testing time tf = Ft100 min cvi = 2.1 Ac m2/year  
  lt100      
Significant strain : assumed failure/reading intervals* ef =            
Calculated rate of axial displacement   dr = efLc         mm/min  
              tf            
Selected machine speed                 mm/min  
*Delete as appropriate

 
  Operator Checked Approved

                                                                                                                                        Form 8C