Civil engineering and structures
Falling-head permeability test
Calculates k = (a*L/(A*t))*ln(h1/h2) for positive heads h1 > h2.
Related calculators
Constant-head permeability test
Calculates k = V*L/(A*Δh*t), where V is the measured flow volume.
Bearing capacity with manual factors
Calculates q_ult = c*Nc + q*Nq + 0.5*gamma*B*Ngamma from manually supplied factors and multipliers.
Boussinesq point-load stress
Calculates vertical stress σ_z below a point load P at radial distance r and depth z.
U to T_v consolidation approximation
Calculates approximate T_v from U: for U <= 0.60 it uses (pi/4)*U^2, for larger U it uses -0.933*log10(1-U)-0.085.
Consolidation time factor
Calculates T_v = c_v*t/H_dr^2 and inverse modes for time, c_v, and drainage path.
Darcy flow through soil
Calculates gradient i = Δh/L, flow Q = k*A*i, and Darcy velocity q = k*i.