Experimental study on excavated foundation of transmission line gravelly soils in gobi area of North

With regard to the transmission line gravelly soil foundation in the gobi area of Northwest China,the full-excavated foundation field prototype tests are carried out to measure the foundation deformations and load bearing capabilities under various working conditions.The feasible construction technology and procedure are discussed.Field mechanism and methods for calculating the uplift bearing capacity are suggested.The empirical calculation formulas and the reasonable design parameters are summarized.The economical benefits of excavated foundation and traditional large digged formation are compared.The environmental advantages of excavated foundation and rigid concrete foundation are analyzed.Based on the test results,the components of the uplift bearing capacity to excavated foundation in the gobi area of Northwest China are put forward: base weight,earth mass weight in the predicted failure plane,and vertical components of shear resistance above the predicted failure plane.The experimental results provide a basis for the design and application of 750 kV compact power transmission line with double circuits on the same tower in Northwest China.