Chapter 3 SLOPE STABILITY AND SEEPAGE CONTROL MEASURES
3.1 General
Slope stability is the potential of soil covered slopes to withstand and undergo movement. Stability is determined by the balance of shear stress and shear strength. A previously stable slope may be initially affected by preparatory factors, making the slope conditionally unstable. Triggering factors of a slope failure can be climatic events can then make a slope actively unstable, leading to mass movements. Mass movements can be caused by increase in shear stress, such as loading, lateral pressure, and transient forces. Alternatively, shear strength may be decreased by weathering, changes in pore water pressure, and organic material.
The field of slope stability encompasses static and dynamic stability of slopes of earth and rock-fill dams, slopes of other types of embankments, excavated slopes, and natural slopes in soil and soft rock. Slope stability investigation, analysis (including modeling), and design mitigation is typically completed by geologists, engineering geologists, or geotechnical engineers. Geologists and engineering geologists can also use their knowledge of earth process and their ability to interpret surface geomorphology to determine relative slope stability based simply on site observations.
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The driving force, due to the weight of the soil, tends to move the soil mass down slope. The resisting force, due to the strength of the soil along the base of the soil mass, or “slip surface,” tends to hold the soil mass in place. If the driving force is greater than the resisting force, the soil mass will slide along the slip surface and a slope stability failure will occur. The potential for failure for a given soil mass is quantified in terms of the Factor of Safety, which is defined as the resisting force divided by the driving force. If the Factor of Safety is greater than 1.0, the soil mass will not
This rock type could prove dangerous, being soft and with little solidness in its structure. Therefore placing the protection over the rock cliffs was a very well thought and planned engineering
Graves, asks him to figure out a 75cent glitch that is in the accounting system.
Two factors contribute to the resistive frictional force; a normal force and the friction coefficient. The normal force is the force holding the person up keeping them from falling towards the center of the earth. On level ground the normal force acts straight up against the acceleration of gravity. On a slope, the normal force is equal to the force of gravity proportional to the cosine of the angle of the slope to horizontal. This portion of gravity attempts to accelerate the person toward the center of the earth, the normal force resists this acceleration. The remaining component of gravity accelerates the body down the hill parallel to the slope, a linear acceleration.
affects the ecosystem. The land's incline prevents some areas to receive and maintain a water
“Hills Like White Elephants”, by Ernest Hemingway, is a short story published in 1927 that takes place in a train station in Spain with a man and a woman discussing an operation. Most of the story is simply dialogue between the two characters, the American and Jig. This couple is at a critical point in their lives when they must decide whether or not to have an abortion. Certain themes arise from this story such as choices and consequences, doubt and ambiguity, and how men and women relate. Hemingway also uses many examples of symbolism in “Hills Like White Elephants”, including descriptions of the surrounding scenery, the hills themselves, and the station where the action takes place. Clearly, this short story crosses timelines to become relevant to both the early twentieth century and modern times.
A community may be defined as a feeling of fellowship with others, as a result of sharing common attitudes, interests and goals. Although each and every community divaricates from the next, each holds a common base ground for tradition and standard. It is in fact tradition and standards of behavior that unify a community to implement a sense of stability. After all, stability is the inescapable quality that bonds a community as one. This imperative factor is in fact one that is investigated in a hopeless quest to find the true meaning of community and its gravitational pull of mankind. The assumption that a community, in essence, exudes a sense of stability may be refuted in three key limitations. Entrusting too much of one’s faith in tradition and community standards can lead to the ultimate dissolution of a community’s health. Furthermore, dwelling on the act of maintaining the tradition and standards of that community can lead to downfall of one’s own being, and individuality. At the cost of the community as a whole, proceeding to maintain these traditions and standards is in the least bit ideal, as values and traditions are ever evolving and most commonly outdated in future composition. In the excerpts of “A Wobegon Holiday Dinner” by Garrison Keillor, “The Amish Charter” by John Hostetler, and “It Takes a Tribe” by David Berreby, the limitations of the assumption that communities provide a sense of stability are refuted on the basis of tradition and social standards.
The Earth’s surface is ever changing, and each region has different rates of change (Westaway, 2017). This is completed through lateral transport processes such as water, wind and mass movement, while ice is one too it doesn’t apply in Australia. Mass movement happens on sloping ground where huge slabs of the ground surface detach and slide or flow downhill (Government of South Australia, 2016). It occurs in Australia due to the extreme wetness causing the soil to be weak and gain mass, or by earthworks such as track cutting. Slope plays a key role in mass movement and virtually any slope steeper that 30% is at risk. South Australia is home to permeable substrate materials, shale, bedrock and depending on
In Hills Like White Elephants, by Ernest Hemingway the reader gets look into a tense conversation between a man and a woman regarding a serious moment in their relationship. Using Deborah Tannen’s theories regarding rapport and report talk I will analyze the talking styles in this short story. The characters in the story are the American and the girl and from what I observed I was able to learn that they speak in report and rapport talk, respectively, just Tannen’s theory would report.
Living in Bangladesh, we have seen quite disastrous mudslides from the past few years. Mudslide is also called a landslide or a land slip. It is a downward mass movement of earth or rock on unstable slopes, including many forms resulting from differences in rock structure, coherence of material involved, degree of slope, amount of included water, extent of natural or artificial undercutting at the base of the slope, relative rate of movement, and relative quantity of material involved. There are numerous facts that can cause a mudslide and there are also numerous effects that it can cause us.
I predict that the as I increase the height of the slope (or the angle
... although we may never be able to understand exactly what soil failures can occur when a natural disasters take place, as time goes on and testing instruments and materials advance we will hopefully have a better understanding of what we can do to avoid soil failures and come up with a better and more sufficient method of improving the soils structure and strength permanently. While researching the information for this report I feel I have a much better understanding for construction geo-technics and foundations especially regarding the deformation, liquefaction and pile information related to this specific event. I hope to carry the information I have learned from this event into the construction field and apply them towards an authentic project that’s taking place and know that the information, regarding soils, I have given input on will be precise and accurate.
Steeper slopes pose increased run-off speeds that can damage the bunds. Such steep slopes require another soil conservation technique such as trenches.
...strous. These landslides were caused by the heavy rainfall which often caused the hills being dug to give way, resulting in massive landslides. The workers cut their way through the continent with dynamite and steam shovels. These engineering maneuvers were slow and time consuming but were completed successfully (McCullough 106-108).
U.S. Geological Survey. Worldwide Overview of Large Landslides of the 20th and 21st Centuries. 6 December 2010. 3 February 2011 .
Geotechnical Engineering covers the engineering properties of soils, the fundamentals of soil mechanics, and the application of geotechnical data and fundamentals to the design of foundation elements, earth-retaining structures, excavations, earth embankments and highway pavements.