Wyniki wyszukiwania - BazTech

1

Efficient and conservative estimation reliability analysis of strip footing on spatially variable c - ϕ soil using random finite element limit analysis

Szabowicz Hubert, Kawa Marek, Puła Wojciech

Studia Geotechnica et Mechanica

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2025

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Vol. 47, nr 1

17--35

EN

The study deals with reliability analysis of strip foundation on spatially variable c - ϕ soil. The spatial variability of soil strength parameters, namely cohesion c and friction angle ϕ is modelled using anisotropic uncorrelated random fields, generated with the Fourier series method. Random finite element limit analysis (RFELA) providing a rigorous lower and upper bound for bearing capacity for individual Monte-Carlo simulations is employed. Additional use of adaptive meshing refinement algorithm leads to a significant reduction of the relative difference between statistical moments of obtained lower and upper bound results. The influence of the horizontal and vertical scales of fluctuation and foundation depths on the mean and standard deviation of the obtained bound moments is investigated. Additionally, the rigorousness of the mean and standard deviation of both considered bounds estimation is checked. As a result of the analysis, a novel approach based on a mixed distribution that combines lower and upper bound moments is introduced. As shown, this approach offers significant benefits by providing conservative and relatively precise measures of reliability which can be obtained in reasonable computation time. The proposed method seems to be adequate for practical engineering reliability analysis of foundation bearing capacity and other limits states problems.

2

Estimating the ultimate limit state of masonry structures from component‑level criteria

Myszor Mariusz, Szabowicz Hubert, Kawa Marek

Materiały Budowlane

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2025

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nr 9

115--121

EN

The article presents the application of Finite Element Limit Analysis (FELA) for assessing the strength of masonry structures. The limit state is determined using both upper and lower bound estimates. The analyses are restricted to a two‑dimensional plane stress problem. The results are presented as limit surfaces corresponding to various orientations of the principal stress axes relative to the masonry material directions. The study shows that the proposed approach to the macroscopic formulation of a masonry strength criterion is computationally efficient compared to conventional Finite Element Method (FEM) simulations. Moreover, it can be effectively employed for defining failure criteria in other classes of composite materials.

PL

W artykule zaprezentowano wykorzystanie analizy granicznej z dyskretyzacją elementami skończonymi do wyznaczania wytrzymałości konstrukcji murowej. Stan graniczny określono w postaci oszacowań: górnego i dolnego. Analizy ograniczono do zadania 2D w płaskim stanie naprężenia. Wyniki zostały zaprezentowane w postaci powierzchni granicznych w przypadku różnych kątów odchylenia osi naprężeń głównych od kierunków materiałowych muru. Wykazano, że zaproponowane podejście do sformułowania makroskopowego kryterium wytrzymałości muru jest efektywne obliczeniowo w porównaniu z analizą metodą elementów skończonych (MES) i może być z powodzeniem stosowane do tego celu.

3

Analysis of underground stratification based on CPTu profiles using high-pass spatial filter

Rainer Jakub, Szabowicz Hubert

Studia Geotechnica et Mechanica

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2020

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Vol. 42, nr 4

355-365

EN

The issue of the stratification of the underground subsoil is one of the principal geotechnical challenges. The development of the Cone Penetration Tests (CPTu) has resulted in the possibility to record parameters in a quasi-continuous way, which provides a very detailed description of the soil response. Such accurate measurements may therefore be treated as a signal or image and be analysed as such. This paper presents the application of high-pass spatial filters to perform soil stratification on the basis of the static penetration test. The presented algorithm has been tested on the test data set provided by the Organizers of TC304 Student Contest on Spatial Data Analysis (September 22, 2019, Hannover, Germany). It provides reasonable results at negligible computational cost and is applicable to most soils, especially if the contrast between the parameters of the adjacent layers is significant.