Correction and simplification of swipe category methods for determining the failure envelope on cohesive soil

Abstract

The failure envelope is commonly used to describe the ultimate bearing capacity under combined loading of offshore foundations. Based on different loading strategies, various methods such as side swipe, probe, sequential swipe, and enhanced swipe methods, have been presented to determine failure envelopes. To improve the accuracy and efficiency of calculation, a simplified modified swipe method is proposed in this paper, and its performance is compared against the other four loading methods in different geological profiles with the influential factors analysed. The performance of different methods under complex conditions and parameter sensitivity are also discussed. It has been found the elastic modulus of soil affects the shape of the failure envelope when the same loading displacement is applied, and that the calculation accuracy of the simplified modified swipe method can be ensured by increasing the modulus or enhancing the loading ratio. The general comparison illustrates that the simplified modified swipe method is effective in terms of accuracy, speed, and ease of implementation and is therefore recommended as an attractive and convenient solution for obtaining failure envelopes.