А Regression Model for Determining the Bearing Capacity of Drilled Piles Using the Dynamic Load Testing Method

The paper considers the experience in implementing an innovative method of press-in impact loading (internationally known as Dynamic Load Test (DLT) in Ukraine when testing soils using full-scale piles, which is based on the principles of the wave theory of impact. The advantages and disadvantages of this test method for different types of piles are shown, and the issues that arise when testing soils using drilled piles, in particular CFA piles, are noted. The paper proposes for the first time the use of statistical methods to build a regression model that determines the bearing capacity of piles based on parallel soil tests by piles using the methods of static press-in loading (internationally known as Static Load Test, SLT) and impact (dynamic) press-in loading (DLT). The factors that significantly affect the mechanics of the interaction between the pile and the soil base when testing soils by piles using the DLT method were formulated and identified. Multiple linear regression models were developed to determine the ultimate resistance and bearing capacity from the elastic deformation of drilled piles based on the DLT results to predict the load-settlement relationship, which is essential for the design of pile foundations. Both correlation and regression analyses of the proposed models were performed; prospects for their improvement were suggested. At this stage of the development of correlation models, we have obtained sufficiently high statistical evaluation results, which indicate technically correct models with strong relationships between variables and high statistical significance. In 2024-2025, the proposed models were field-tested at a real construction site when testing piles using the DLT method, where the deviations of the determined values of Fe and Fu for CFA piles were within 5% of the values determined using the SLT method.