Geotechnical Engineering Analysis

Introduction

The goal of this article is to offer I some direction on the creation and execution of a slope analysis using SLOPE/W, as well as a concise introduction to the idea of numerical modelling.

In the Geotechnical Engineering Analyses unit, the fundamental concepts are the foundations of the learning, and as a result, the emphasis is on essential analytical models as well as solutions that can be simply computed by hand as they clearly explain the main ideas. In addition, the fundamental assumptions are the fundamental elements of learning. However, as was discussed in previous courses, modelling tools are extensively utilised in business (as well as research) regardless of the computing power and precision they provide. Because of this, it is essential that individuals understand what goes into modelling (Al-Najjar,2022).

SLOPE/W 

The modelling software Geo studio, used by geotechnical engineers as well as earth scientists, includes the programme SLOPE/W. It has a collection of standalone programmes that can simulate different types of ground behaviour:

SLOPE/W -Slope stability evaluation in soil and rock

SEEP/W - Flow of groundwater

SIGMA/W -Geotechnical and structural study of strain and deformation

QUAKE/W -Liquidity loss and dynamic loading in earthquakes

TEMP/W -Phase transition and heat transfer

CTRAN/W-Movement of Contaminants

AIR/W -Transport of Air via Mine Waste

Each of these programmes may work in tandem with the others, building upon the findings of the previous one. The porous material distribution of pressure in a water-retaining embankment caused by seepage, calculated using SEEP/W, may be imported through SLOPE/W for a more precise slope stability study, for instance. Integrating SEEP/W data into CTRAN/W allows for more precise modelling of contaminant transport, taking into account groundwater dynamics (Baghbani,2022).

Getting Started with SLOPE/W 

Geo Studio's key features are

• Choose "Student Licence" from the main menu.   
• To access the SI unit option, set the template type to "Metric."  
• Choose SlOPE/W as Ir method of analysis.  

All GeoStudio projects are stored with the gsz suffix, so they may be opened using any of the suite's programmes (such as SIGMA/W and SEEP/W).

The main parts of an SLPE/W solution for a slope stability issue are: 

• Project Scope Statement  
• Geometric definitions 
• Characterising the soil and classifying it geographically 
• The nature of the water table, defined 
• Finding a solution 
• Putting the findings on display (critical slip circles, graphs, etc.)

Information on how to carry out the aforementioned modelling procedures are provided below (Garg,2022).  

Defining the Project 

Defining the scope of the project entails the following stages:

1. Type the project's name as well as brief description here.

1. Choose Form of Analysis

1. To change the PWP condition, click the Tab key.  

1. In the "Slip surface" menu, choose whether the surface slides left to right, right to left, or uses passive mode. The passive method will not be discussed in the current assignment.

There are two approaches to define a set of concentric trial slip surfaces: (a) entry and exit, as well as (b) grid and radius.  The Grid as well as Radius technique was discussed in class, thus it is appropriate for Ir homework.   

1. Adjust the appropriate geometry as well as factor of safety settings under the Advanced menu.

Geometry 

The next stage is to sketch the geometry of the issue, keeping in mind the slope measurements as well as the various material zones. Referring to Figure 3, use the "sketch>lines" menu option to do this.

Figure-3: Drawing the Geometry 

At the point where the green horizontal line and the red downward line meet, x = 0 and y = 0, respectively.

Material Properties 

Permeability values for new materials are calculated in "Define...Materials" using a hydraulic conductivity (permeability) function. To add a new material, choose "Add," then label it appropriately. Figure 4 shows the appropriate pane.

There are 3 distinct material models available in the learners edition of SLOPE/W to reflect the numerous soil types:

• None 

This may be used in analysis to represent the lack of a model component, such as impervious bedrock.

• Mohr – Coulomb  

Common methods for calculating shear strength use the Mohr-Coulomb equations. According to the needs of the task at hand, the total strength parameters or functional strength parameters may be used as the fundamental strength characteristics.

Basic Parameters

• Measured in:  What one metric tonne of dirt weighs in total.
• Cohesion:  The cohesiveness of the shear force.
• Phi:  The soil's friction angle

Bedrock (Impenetrable) Model

A slip surfaces cannot penetrate the material, as predicted by the Bedrock (Impenetrable) strength concept. This alternative does not constitute a model of strength but rather a means of indirectly affecting the form of the slip patches (Khan,2022).

Figure-5: Draw Regions

Defining Water Table Condition 

To further characterise the pore pressure generated by water in soil layers, we will now include a piezometric line. 

In the Define Project box, under "Pore Water Pressure (PWP)," choose the piezometric line option.  Create the piezometric line using Draw/Pore Water Pressure.  It might be vertical or diagonal. To insert a piezometric line, go to "Define > Pore Water Pressure," click "Add," and finally provide the line's x, y dimensions.  It might be vertical or diagonal.  

Figure-6: Water Layer

Defining Grid and Radios For the SLIP 

The Grid as well as Radius technique requires the specification of a grid.  

Select "Draw>Slip surface>Grid" to bring up the grid (Liu,2022).  

Every dot on the grid will serve as a focal point, and the corners will be defined in an anticlockwise fashion, beginning with the top left corner.  

A box's radius is specified by the lines that lie within it (with each of the four corners defined anticlockwise, beginning at the top left).   

Running the Analysis 

I may proceed with the analysis now that I have a clear understanding of the issue at hand. If I've carefully laid out all the criteria, pushing "start" is as easy as it seems in Error! Error locating referenced material Analysis will be conducted using SLOPE/W. SEEP/W will take I to the Results tab (error!) after the analysis is done. b) No matching references could be located.

Viewing the Results

Once I've found the solution, the crucial slip surface will automatically be shown in the window.

Numerous slip grounds with a range of safety factors may be shown by choosing the quantity of slip circulars from View/Preferences.

I can view what each of the practise circles in the table looks like by choosing the Draw or Select Slip Surfaces option. The most important one is listed first, followed by the others with their safety factors, centred coordinates, and radii.

Clicking "view slice information" will bring up the slice's specifics. In addition to the crucial slip circle and force polygons, I can also copy data and charts.

Some of the circles I draw won't make any sense mathematically. If I get an error message, I can usually determine its cause by going to the documentation menu and looking up the error message numbers that were shown within the error message itself. The SLOPE/W programme has more in-depth instructions on how to use it on BB (Otake,2022).

Discussion and recommendation

I have been presented with an overview of the essential procedures to design, execute, as well as analyse a simple SLOPE/W model by reading the paper. Even while this has been in relation to SLOPE/W particularly, the basic principles of issue formulation, geometry, material qualities, boundary conditions, and so on are common to digital model. 

Although modelling using computers is a very useful and potent engineering tool, one must exercise caution when use it and not place too much stock in the results. In order to be successful as the next engineer, it is essential that I have a solid understanding of both the advantages and the limitations of the method known as numerically modelling.

Reference

Al-Najjar, O. A., Y. S. Wudil, U. F. Ahmad, Omar S. Baghabra Al-Amoudi, Mohammed A. Al-Osta, and M. A. Gondal. "Applications of laser induced breakdown spectroscopy in geotechnical engineering: a critical review of recent developments, perspectives and challenges." Applied Spectroscopy Reviews (2022): 1-37.

Baghbani, Abolfazl, Tanveer Choudhury, Susanga Costa, and Johannes Reiner. "Application of artificial intelligence in geotechnical engineering: A state-of-the-art review." Earth-Science Reviews 228 (2022): 103991.

Garg, Ankit, Yuanxu Huang, Huang He, Xilong Huang, Peng Lin, Kanishk Kalra, Guoxiong Mei, Vaibhav Khandare, and Lovepreet Singh. "Geotechnical engineering educational modules demonstrating measurement and regulation of soil moisture." Computer Applications in Engineering Education 30, no. 3 (2022): 973-985.

Khan, Farhan, Bhumika Das, Sri Ram Krishna Mishra, and Mohan Awasthy. "A review on the feasibility and application of geospatial techniques in geotechnical engineering field." Materials Today: Proceedings 49 (2022): 311-319.

Liu, Dongsheng, Hanlong Liu, Yue Wu, Wengang Zhang, Yanlei Wang, and M. Santosh. "Characterization of geo-material parameters: Gene concept and big data approach in geotechnical engineering." Geosystems and Geoenvironment 1, no. 1 (2022): 100003.

Otake, Yu, Kyohei Shigeno, Yosuke Higo, and Shogo Muramatsu. "Practical dynamic reliability analysis with spatiotemporal features in geotechnical engineering." Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards 16, no. 4 (2022): 662-677.