Discussion on the Formula of Anti-extraction Calculation for Extended Foundation on Wind-borne Sand Deposit

Based on analyzing the mechanism of fraction for anti-extraction soil by using the results of in-side model test about wind-borned sand deposit foundation,three stressing process of the ultimate bearing capacity in soil is given,and the basic formual for anti-extraction capacily calculation is established.Compared with other methods at present,the accuracy of the calculation result is several times over that of others.Because the scope of application isn't limited by width-to-depth ratio,it is very convenient for widely application.