(1) loading mode adopts slow maintenance loading mode; (2) Loading shall be carried out in stages, and the loading increment of each stage is110 of the ultimate bearing capacity of pile foundation, and it can be increased by1/5 in the first stage; (

3) Time interval for measuring and reading the settlement of the pile top: after all levels of loads are applied, measure and read the settlement of the pile top at the 5th,15th, 30th, 45th and 60th minutes, and then every 60min; (4) Standard of relative stability of settlement: the settlement of the pile top within one hour shall not exceed 0. 1mm, which occurs twice in a row (from the 30th minute after the graded load is applied, it shall be calculated as the settlement observation value of three times in a row every 30 minutes 1.5h); (5) Loading termination conditions: In any of the following circumstances, the loading can be terminated: a. Under a certain level of load, the settlement of the pile top is 5 times greater than that under the previous level of load, and the total settlement of the pile top exceeds 40mm；; B. Under a certain load, the settlement of the pile top is twice that of the previous load, and it still fails to reach the relative stability standard after 24 hours; C. The load has reached the limit value of bearing capacity; D the pullout resistance of the anchor pile has reached the allowable value; When the E. Q ~ S curve changes slowly, the total settlement that can be loaded to the pile top is greater than 60 mm ~ 80 mm ... (6) Unloading: the unloading amount of each stage is twice the loading amount. After unloading at each stage, measure and read the residual settlement every 15, 15 and 30 minutes, and then unload the primary load. After all unloading, test and read once every 3-4 hours, and then terminate the test.