Evaluation of foundation reliability based on the settlement of a multi-layer base

Improving the quality of foundation design solutions for buildings and structures is inextricably linked to assessing their reliability. However, methods for such assessment have been vastly underdeveloped to date. The principle of limit state design adopted in domestic foundation engineering relies on the concept of design load values and soil characteristics. This concept also includes reliability factors in the form of load and soil reliability factors. These factors represent estimates of the methods used to determine individual parameters. At the same time, reliability, in principle, implies the failure-free operation of the entire system - in this case, the structure's foundation and soil mass. The probability of assessing reliability, known as the reliability level, presupposes the presence of conditions that the design solution must meet. Typically, these conditions relate to bearing capacity and foundation deformations. The probability of meeting these conditions, which are considered as specified functions of random variables, characterizes the reliability of the foundation structure.

The procedure for determining the reliability level is defined as follows. First, the random parameters of the condition being tested and their numerical characteristics up to the fourth-order central moments are established. Second, the numerical characteristics of the condition are calculated as a random function, previously linearized. Third, the probability of the condition being satisfied is calculated using an arbitrary distribution law in the form of a Charlier series. This approach to assessing the reliability of foundation structures is sufficiently justified and can be used in design practice. The application of this method was considered for assessing the reliability of soil foundations based on bearing capacity and deformation. However, in recent revisions of regulatory documents, the settlement calculation method has been significantly modified. The purpose of this article was to present an algorithm for assessing the reliability of the modernized method for calculating the settlement of soil foundations.

1. Silin Ya. V. On the application of catastrophe theory to assessing the reliability of oil and gas complex equipment. Northern Region: Science, Education, Culture. 2013;(28):62–69. (In Russ.).

2. Utkin V. S. Assessment of reliability and bearing capacity of building structures based on the theory of fuzzy sets and possibility theory: specialty 05.23.17 ‘Structural Mechanics’. Dissertation for the Degree of Doctor of Engineering. Utkin Vladimir Sergeevich. 2002. 395 p. (In Russ.).

3. Gnedenko B. V., Belyaev Yu. K., Soloviev A. D. Mathematical methods in reliability theory. main reliability characteristics and their statistical analysis: Monograph. 2nd ed., corrected and added. Moscow: LIBROKOM; 2012. 582 p. (Series: Physico-Mathematical Heritage: Mathematics (Probability Theory)). (In Russ.).

4. Venttsel E. S., Ovcharov L. A. Applied problems of probability theory. Moscow: Radio i Svyaz; 1983. 416 p. (In Russ.).

5. Pugachev V. S., Sinitsyn I. N. Structural theory of complex stochastic systems. Informatics and Its Applications. 2011;2(5):4–16. (In Russ.).

6. Gmurman V. E. Probability theory and mathematical statistics. Moscow: Yurait; 2003. 427 p. (In Russ.).

7. SNiP 2.02.01–83*. Foundations of buildings and structures. Moscow: TsPP; 2006. 48 p. (In Russ.).

8. SP 22.13330.2016. Foundations of buildings and structures. Updated version of SNiP 2.02.01-83*. Moscow: Standartinform; 2016. 228 p. (In Russ.).

9. Ermolaev N. N., Mikheev V. V. Reliability of structure foundations. Leningrad: Stroyizdat, Leningrad Branch; 1976. 152 p. (In Russ.).

10. Karaulov A. M., Korolev K. V., Fedosin K. A. Determining the reliability level of the soil foundation settlement condition. Hydropower. Hydraulic Engineering. New Developments and Technologies: Abstracts of the Sixteenth Scientific and Technical Conference. St. Petersburg: All-Russian Vedeneev Hydraulic Engineering Research Institute; 2024. P. 148–150. (In Russ.).