AASHTO HB-17 Figure 5.6.2A.b shows simplified earth pressures for cantilevered walls with discrete elements. The equation shown for resistance in rock is (as I read it):
Pp = (s*D)/{[1+tan(beta_prime)]*[D+2^0.5*b]}
Is this formula correct? It seems to me that this reading of the equation would tend to reduce the allowable Pp as the element width b increased. I suspect that the equation should read:
Pp = {(s*D)/[1+tan(beta_prime)]}*[D+2^0.5*b]
Confirmation of the second reading would be appreciated (provided that it is the correct answer!!!).
Note that this was also posted to the foundation engineering forum.
Jeff
Jeffrey T. Donville, PE
TTL Associates, Inc.
Pp = (s*D)/{[1+tan(beta_prime)]*[D+2^0.5*b]}
Is this formula correct? It seems to me that this reading of the equation would tend to reduce the allowable Pp as the element width b increased. I suspect that the equation should read:
Pp = {(s*D)/[1+tan(beta_prime)]}*[D+2^0.5*b]
Confirmation of the second reading would be appreciated (provided that it is the correct answer!!!).
Note that this was also posted to the foundation engineering forum.
Jeff
Jeffrey T. Donville, PE
TTL Associates, Inc.
