Wyniki wyszukiwania - BazTech

1

Influence of grouting pressure volatility on additional response of adjacent pile foundation in shield construction

Zhang Chuan-Chuan, Li Dan-Mei, Zhang Jun, Yu Tong-Sheng, Chen Qiang

Journal of Theoretical and Applied Mechanics

|

2022

|

Vol. 60 nr 1

33--47

EN

Soil parameters along the heading direction are subjected to spatial variability during shield construction, so grouting pressure requires constant adjustment to ensure ground stress sta- bility. This causes grouting pressure to fluctuate around the design pressure/curve. There- fore, the influence of the grouting pressure volatility on the adjacent loaded-pile foundation should be considered in shield tunneling. In this study, a refined numerical simulation of the shield construction process is conducted using the Fast Lagrangian Analysis of Continua in Three Dimensions (FLAC3D) software. A total of 300 groups of grouting pressure pa- rameters with a skewed normal distribution are input into the numerical model. Then, the influence of the construction parameter uncertainty on the adjacent loaded-pile foundation is analyzed. Finally, the back analysis method is conducted based on the monitored data to evaluate how the construction process affects the pile foundation. The calculation results are compared with those of the traditional finite element method. The results indicate that in the tunneling process, the grouting pressure fluctuation greatly affects the additional bend- ing moment of the adjacent pile foundation. Under the influence of the grouting pressure, the additional axial force and additional bending moment of the pile foundation also follow the skewed normal distribution. The back analysis results of the pile foundation are greater than those of the typical numerical method by about 60% 100%, that is using the back analysis calculation results to evaluate the pile foundation additional response can reduce the risk.

2

New open-source ANSYS-SolidWorks-FLAC3D geometry conversion programs

Bock S.

Journal of Sustainable Mining

|

2015

|

Vol. 14, iss. 3

124--132

EN

Numerical calculations are used increasingly often to obtain a stress-strain state in many engineering problems. A popular program for this type of calculation which makes use of the finite difference method (a continuous method) is Itasca's FLAC3D. However, an important limitation of FLAC3D is the difficulty of geometry creation. This paper presents new open-source programs allowing the preparation of numerical models in a third-party software (ANSYS, SolidWorks) and their conversion to internal FLAC3D geometry files. The converters have been written in BASH-scripting language and published under the terms of the GNU General Public License, which allows the free distribution and/or modification of the software with some limitations.

3

Impact of bearing plates dimensions on interaction of mine workings support and rock mass

Rotkegel M., Bock S.

Journal of Sustainable Mining

|

2015

|

Vol. 14, iss. 1

12--20

EN

The aim of the research presented in this article is to assess the impact of bearing plates dimensions on the interaction of steel arch support and rock mass. The analysis of the bearing plates was based on laboratory tests and numerical calculations using the FLAC3D program (a finite difference method) and the strain-hardening/softening model based on prescribed variations of Mohre-Coulomb properties. The article presents the results of laboratory tests on selected bearing plates and the results of numerical analysis of the interaction between the bearing plates and rock mass with coal, clay stone and sandstone properties.