In recent years， with the gradual expansion and development of high-voltage transmission lines and offshore wind power， spiral anchors have been applied in fields such as construction and power engineering. Therefore， higher demands have been put forward for the basic load-bearing performance and usage scenarios. However， the current calculation model for the basic bearing capacity of helical anchors is only proposed for sand and clay. When the soil exhibits cohesive force and internal friction angle simultaneously in the soil conditions， the applicability of the bearing capacity calculation formula has not been fully validated. Therefore， this study conducted in-situ experimental research and numerical analysis on inclined helical single anchors in silty clay， elucidated the force transmission path under the tension and compression loads of inclined helical anchors， revealed the failure modes in complex stratified soils， demonstrated the applicability of the current bearing capacity calculation methods for silty clay， and established a vertical deformation calculation model for helical anchors based on the t-z curve method. The results indicated that the soil disturbance caused by helical anchor drilling resulted in a higher compressive bearing capacity than an uplift bearing capacity. The load borne by the top anchor plate under upward and compression conditions accounted for about 15% of the total load. When calculating the bearing capacity according to the regulation， it was not appropriate to consider both c and φ simultaneously； instead， they should be considered separately. When the corrected bearing capacity matched the actual bearing capacity well， the calculated vertical deformation and load displacement curves matched well， and the theoretical formula demonstrated high prediction accuracy.
Zhang et al. (Wed,) studied this question.