Research On Ultimate Lateral Resistance Of Piles In Saturated Degradation Sands

The design method for laterally loaded piles in static conditions is quite explicit. But the excess pore water pressure generated in saturated sands by earthquakes will result in the degradation in soil lateral resistance. Predicting the bearing capacity of pile foundations in liquefied soil lacks a realistic procedure, the common practice employed is to multiply the p-y curves by a coefficient, the value of the coefficient is different in the researches. Also the soil-pile interaction in saturated sands with different residual pore water pressures is very complex, so a series of researches were conducted to analyze lateral resistance of soil with different residual pore water pressures.TThe excess pore water pressure in the saturated sand was controlled by applying the back pressure to the stratum, which was used to simulate the degraded saturated stratum with the residual pore water pressure. Model tests of the soil-pile interaction were conducted to study the soil-pile interaction and ultimate lateral resistances of single pile in degraded saturated sands with an increase of the residual pore water pressure.The formula of the soil ultimate lateral resistance is founded in model test condition according to the API codes. The formula found the link between the sand friction angles and the ultimate lateral resistance.At last, a series of triaxial tests are completed to obtain the friction angle of the sand with different residual pore water pressures. The theoretical ultimate lateral resistance can be obtained using the angles. Comparing the theoretical value with the ultimate lateral resistance determined by model tests, we find good agreement between them when the residual pore water pressure ratio was less than 0.75. The theoretical value was less than the model test result if the ratio was 1.0.