SPave

The StreetPave Framework

Variables

  • %Growth=annual traffic growth rate, %
  • %SlabsCracked=allowable percent of slabs cracked at the end of design life, %
  • σeq,N=equivalent stress for axle load N, psi
  • μ=Poisson’s ratio of the concrete
  • ADTTDesign=average trucks per day in design lane over the design life, trucks/day
  • ADTTInput=current 2-way average daily truck traffic (ADTT), trucks/day
  • AxlesPerN=axles per 1,000 trucks for an axle load, axles/1k trucks
  • C1=adjustment factor for support stiffness
  • C2=adjustment for edge support
  • CV=coefficient of variation of concrete
  • DesignLife=design life, years
  • DirDist=directional distribution, %
  • EC=modulus of elasticity of the concrete pavement, psi
  • EDN=erosion damage for axle load N, %
  • EDtotal=total erosion consumed, %
  • f1=adjustment factor for the effect of axle loads and contact area
  • f2=adjustment factor for a slab with no edge support
  • f3=adjustment factor for 6% of trucks at the slab edge
  • f4=adjustment factor for concrete strength gain
  • f5=adjustment factor for the effect of axle loads
  • f6=adjustment factor for edge support and/or dowels
  • f7=adjustment factor for slab edge loading
  • FDN=fatigue damage for axle load N, %
  • FDtotal=total fatigue consumed, %
  • h=concrete pavement slab thickness, in.
  • kdesign=composite static k-value of the subgrade and subbase(s), psi/in.
  • l=radius of relative stiffness of the slab-subgrade system, in.
  • LaneDist=design lane distribution, %
  • Me,N=maximum equivalent moment for axle load N, psi
  • MRconcrete=modulus of rupture (flexural strength) of the concrete, psi
  • MRdesign=design modulus of rupture (flexural strength), psi
  • Nerosion,N=allowable erosion load repetitions for axle load N
  • Nfatigue,N=allowable fatigue load repetitions for axle load N
  • p=probability of failure, %
  • pc,N=maximum pressure at slab-foundation interface for axle load N, psi
  • PN=power (rate of work) for axle load N
  • R=reliability of the design, %
  • re=residual strength for macrofiber or steel fiber reinforced concrete, %
  • RepetitionsN=total expected repetitions of an axle load, reps
  • SAL=single axle load, kips
  • SRN=stress ratio for axle load N
  • TAL=tandem axle load, kips
  • TotalTrucks=total number of trucks in design lane over the design life, trucks
  • TRI=tridem axle load, kips