Geotechnical Engineering

DHARM 180 GEOTECHNICAL ENGINEERING Two simple cases will be dealt with in regard to the determination of the top flow line: Dis ...

DHARM SEEPAGE AND FLOW NETS 181 B C D F AB S KJ Top flow line P(x, z) Kozenys base parabola ht z Q H G C M x 0/3(EB) E D d Direc ...

DHARM 182 GEOTECHNICAL ENGINEERING The value of S may be determined, either graphically or analytically. The graphical approach ...

DHARM SEEPAGE AND FLOW NETS 183 downstream slope are designated G and E respectively, EF and GE are designated a and ∆a respecti ...

DHARM 184 GEOTECHNICAL ENGINEERING The top flow line in each case is in close agreement with the parabola, except for a short po ...

DHARM SEEPAGE AND FLOW NETS 185 One of the assumptions in the method is that length GH is equal to its projection on the vertica ...

DHARM 186 GEOTECHNICAL ENGINEERING 1 ht E a a F 2 4 3 d 0 Fig. 6.20 Graphical solution based on L. Casagrande’s method z 1 z 2 M ...

DHARM SEEPAGE AND FLOW NETS 187 d x F AB Top flow line ht E a z a sina a J Fig. 6.22 Schaffernak and Iterson’s solution for α &l ...

DHARM 188 GEOTECHNICAL ENGINEERING ht r 0 l r b Impervious C of well of radius ro Fig. 6.23 Radial flow net for seepage into a w ...

DHARM SEEPAGE AND FLOW NETS 189 It is interesting to note that this is a one-dimensional case, since the only space variable is ...

DHARM 190 GEOTECHNICAL ENGINEERING Axis of radial flow net h=0 r=r¢ 0 h=ht Fig. 6.25 Radial flow net for spherically radial flow ...

DHARM SEEPAGE AND FLOW NETS 191 (d) The fact that all transitions are smooth and are of elliptical or parabolic shape should be ...

DHARM 192 GEOTECHNICAL ENGINEERING 6.8.5 Analogy Methods Lapalce’s equation for fluid flow also holds for electrical and heat fl ...

DHARM SEEPAGE AND FLOW NETS 193 sand becomes ‘‘Quick’’ or ‘‘Alive’’ at this gradient; this is only a conditions and not a type o ...

DHARM 194 GEOTECHNICAL ENGINEERING The upward force of seepage is h. γw A, as is in the left hand side of Eq. 6.32. In uniform f ...

DHARM SEEPAGE AND FLOW NETS 195 With a factor of safety of 2.0 against piping, Gradient, i = ic 2 1 0725 2 = . = 0.53625 But i = ...

DHARM 196 GEOTECHNICAL ENGINEERING Referring to Fig. 6.27, the effective stress at the top of sand stratum goes on getting reduc ...

DHARM SEEPAGE AND FLOW NETS 197 Quantity of seepage per meter length of wall UV W q = k. H. n n f d Impervious h = 2.5 m Perviou ...

DHARM 198 GEOTECHNICAL ENGINEERING or S = ()92^22 +− m = 4.77 m 30 92 The quantity of seepage per metre unit length of the dam q ...

DHARM SEEPAGE AND FLOW NETS 199 SUMMARY OF MAIN POINTS Flow of water through soil under a hydraulic gradient is called ‘‘Seepag ...