Loess As a Collapsible Soil: Some Basic Particle Packing Aspects
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Determination of Geotechnical Properties of Clayey Soil From
DETERMINATION OF GEOTECHNICAL PROPERTIES OF CLAYEY SOIL FROM RESISTIVITY IMAGING (RI) by GOLAM KIBRIA Presented to the Faculty of the Graduate School of The University of Texas at Arlington in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE IN CIVIL ENGINEERING THE UNIVERSITY OF TEXAS AT ARLINGTON August 2011 Copyright © by Golam Kibria 2011 All Rights Reserved ACKNOWLEDGEMENTS I would like express my sincere gratitude to my supervising professor Dr. Sahadat Hos- sain for the accomplishment of this work. It was always motivating for me to work under his sin- cere guidance and advice. The completion of this work would not have been possible without his constant inspiration and feedback. I would also like to express my appreciation to Dr. Laureano R. Hoyos and Dr. Moham- mad Najafi for accepting to serve in my committee. I would also like to thank for their valuable time, suggestions and advice. I wish to acknowledge Dr. Harold Rowe of Earth and Environmental Science Department in the University of Texas at Arlington for giving me the opportunity to work in his laboratory. Special thanks goes to Jubair Hossain, Mohammad Sadik Khan, Tashfeena Taufiq, Huda Shihada, Shahed R Manzur, Sonia Samir,. Noor E Alam Siddique, Andrez Cruz,,Ferdous Intaj, Mostafijur Rahman and all of my friends for their cooperation and assistance throughout my Mas- ter’s study and accomplishment of this work. I wish to acknowledge the encouragement of my parents and sisters during my Master’s study. Without their constant inspiration, support and cooperation, it would not be possible to complete the work. -
A Study of Unstable Slopes in Permafrost Areas: Alaskan Case Studies Used As a Training Tool
A Study of Unstable Slopes in Permafrost Areas: Alaskan Case Studies Used as a Training Tool Item Type Report Authors Darrow, Margaret M.; Huang, Scott L.; Obermiller, Kyle Publisher Alaska University Transportation Center Download date 26/09/2021 04:55:55 Link to Item http://hdl.handle.net/11122/7546 A Study of Unstable Slopes in Permafrost Areas: Alaskan Case Studies Used as a Training Tool Final Report December 2011 Prepared by PI: Margaret M. Darrow, Ph.D. Co-PI: Scott L. Huang, Ph.D. Co-author: Kyle Obermiller Institute of Northern Engineering for Alaska University Transportation Center REPORT CONTENTS TABLE OF CONTENTS 1.0 INTRODUCTION ................................................................................................................ 1 2.0 REVIEW OF UNSTABLE SOIL SLOPES IN PERMAFROST AREAS ............................... 1 3.0 THE NELCHINA SLIDE ..................................................................................................... 2 4.0 THE RICH113 SLIDE ......................................................................................................... 5 5.0 THE CHITINA DUMP SLIDE .............................................................................................. 6 6.0 SUMMARY ......................................................................................................................... 9 7.0 REFERENCES ................................................................................................................. 10 i A STUDY OF UNSTABLE SLOPES IN PERMAFROST AREAS 1.0 INTRODUCTION -
The Distribution of Silty Soils in the Grayling Fingers Region of Michigan: Evidence for Loess Deposition Onto Frozen Ground
Geomorphology 102 (2008) 287–296 Contents lists available at ScienceDirect Geomorphology journal homepage: www.elsevier.com/locate/geomorph The distribution of silty soils in the Grayling Fingers region of Michigan: Evidence for loess deposition onto frozen ground Randall J. Schaetzl ⁎ Department of Geography, 128 Geography Building, Michigan State University, East Lansing, MI, 48824-1117, USA ARTICLE INFO ABSTRACT Article history: This paper presents textural, geochemical, mineralogical, soils, and geomorphic data on the sediments of the Received 12 September 2007 Grayling Fingers region of northern Lower Michigan. The Fingers are mainly comprised of glaciofluvial Received in revised form 25 March 2008 sediment, capped by sandy till. The focus of this research is a thin silty cap that overlies the till and outwash; Accepted 26 March 2008 data presented here suggest that it is local-source loess, derived from the Port Huron outwash plain and its Available online 10 April 2008 down-river extension, the Mainstee River valley. The silt is geochemically and texturally unlike the glacial fl Keywords: sediments that underlie it and is located only on the attest parts of the Finger uplands and in the bottoms of Glacial geomorphology upland, dry kettles. On sloping sites, the silty cap is absent. The silt was probably deposited on the Fingers Loess during the Port Huron meltwater event; a loess deposit roughly 90 km down the Manistee River valley has a Permafrost comparable origin. Data suggest that the loess was only able to persist on upland surfaces that were either Kettles closed depressions (currently, dry kettles) or flat because of erosion during and after loess deposition. -
Geotechnical Manual 2013 (PDF)
2013 Geotechnical Engineering Manual Geotechnical Engineering Section Minnesota Department of Transportation 12/11/13 MnDOT Geotechnical Manual ii 2013 GEOTECHNICAL ENGINEERING MANUAL ..................................................................................................... I GEOTECHNICAL ENGINEERING SECTION ............................................................................................................... I MINNESOTA DEPARTMENT OF TRANSPORTATION ............................................................................................... I 1 PURPOSE & OVERVIEW OF MANUAL ........................................................................................................ 8 1.1 PURPOSE ............................................................................................................................................................ 8 1.2 GEOTECHNICAL ENGINEERING ................................................................................................................................. 8 1.3 OVERVIEW OF THE GEOTECHNICAL SECTION .............................................................................................................. 8 1.4 MANUAL DESCRIPTION AND DEVELOPMENT .............................................................................................................. 9 2 GEOTECHNICAL PLANNING ....................................................................................................................... 11 2.1 PURPOSE, SCOPE, RESPONSIBILITY ........................................................................................................................ -
S41598-021-96384-7.Pdf
www.nature.com/scientificreports OPEN A mechanical insight into the triggering mechanism of frequently occurred landslides along the contact between loess and red clay Baoqin Lian1, Xingang Wang1*, Kai Liu1, Sheng Hu2 & Xiao Feng3 The triggering mechanism and movement evolution of loess-red clay landslides, which occurred frequently along the contact between the loess and red clay on the Loess Plateau, are closely related to the mechanical properties of the contact surface. This work presents an experimental investigation on loess, clay and loess-red clay interlaminar (LRCI) samples obtained from a typical loess-red clay landslide in northern part of Shaanxi province of China, using a series of ring shear tests, microscopic observation and scanning electron microscopy tests, in an attempt to explore the mechanical behavior of loess, clay and LRCI samples with variation in moisture content, normal stress and shear rate. The results revealed that for all specimens, both the peak shear strength τp and the residual shear strength τr decreased with increasing moisture content, among which, moisture content has the greatest infuence on the τp and τr of red clay, followed by the LRCI specimen, and the loess specimen is least afected by moisture content. Meanwhile, exponential functions describing the correlations between shear strength and moisture content of LRCI, red clay and loess specimens were proposed. Furthermore, the macroscopic morphological characteristics and the microstructure of shear surface obtained from the LRCI specimens showed that a localized water accumulation was built up within the shear surface as the water content increases to some extent, and a high degree of liquefaction developed within shear surface when the moisture content reached to the saturate degree. -
Summarization and Comparison of Engineering Properties of Loess in the United States
Summarization and Comparison of Engineering Properties of Loess in the United States J. B. SHEELER, Associate Professor of Civil Engineering, Iowa State University •LARGE deposits of loess are found in many parts of the United States, but published values of the engineering properties of loess are relatively scarce. The data in this paper were gathered to indicate similarities and compare the properties of loess from one area with another. Loess is composed primarily of rather loosely arranged angular grains of sand, silt, and clay. Silt is usually the dominant size. Calcite is also generally present in amounts ranging from zero to more than 10 percent of the total soil.. The aeolian hypothesis of loess deposition is compatible with the physical charac teristics of undisturbed loess masses. This hypothesis states that fine-grained ma terial was transported, sorted, and redeposited by wind action and thus became loess. During deposition, moisture and clay minerals are believed responsible for cementing the coarser grains together to form a loose structure. The loess is therefore subject to loss of shear strength due to water softening the clay bonds and to severe consolida tion caused by a combination of loading and moisture. Loess is usually thought of as an aeolian material that was deposited thousands of years ago and has remained in place since the time of deposition. Loess that has been eroded and redeposited is often referred to as redeposited loess, reworked loess or more simply as a silt deposit. This implies that the word loess indicates an aeolian soil, undisturbed since deposition. Certain engineering properties of loess, such as shear strength, are quite drastically changed by erosion and redeposition. -
Liquid Silts - Their Occurrence and Distribution in Loess Robert Odell Lamb Iowa State University
Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1985 Liquid silts - their occurrence and distribution in loess Robert Odell Lamb Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Civil Engineering Commons Recommended Citation Lamb, Robert Odell, "Liquid silts - their occurrence and distribution in loess " (1985). Retrospective Theses and Dissertations. 7866. https://lib.dr.iastate.edu/rtd/7866 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. INFORMATION TO USERS This reproduction was made from a copy of a document sent to us for microfilming. While the most advanced technology has been used to photograph and reproduce this document, the quality of the reproduction is heavily dependent upon the quality of the material submitted. The following explanation of techniques is provided to help clarify markings or notations which may appear on this reproduction. 1.The sign or "target" for pages apparently lacking from the document photographed is "Missing Page(s)". If it was possible to obtain the missing page(s) or section, they are spliced into the film along with adjacent pages. This may have necessitated cutting through an image and duplicating adjacent pages to assure complete continuity. 2. When an image on the film is obliterated with a round black mark, it is an indication of either blurred copy because of movement during exposure, duplicate copy, or copyrighted materials that should not have been filmed. -
Step 2-Soil Mechanics
Step 2 – Soil Mechanics Introduction Webster defines the term mechanics as a branch of physical science that deals with energy and forces and their effect on bodies. Soil mechanics is the branch of mechanics that deals with the action of forces on soil masses. The soil that occurs at or near the surface of the earth is one of the most widely encountered materials in civil, structural and architectural engineering. Soil ranks high in degree of importance when compared to the numerous other materials (i.e. steel, concrete, masonry, etc.) used in engineering. Soil is a construction material used in many structures, such as retaining walls, dams, and levees. Soil is also a foundation material upon which structures rest. All structures, regardless of the material from which they are constructed, ultimately rest upon soil or rock. Hence, the load capacity and settlement behavior of foundations depend on the character of the underlying soils, and on their action under the stress imposed by the foundation. Based on this, it is appropriate to consider soil as a structural material, but it differs from other structural materials in several important aspects. Steel is a manufactured material whose physical and chemical properties can be very accurately controlled during the manufacturing process. Soil is a natural material, which occurs in infinite variety and whose engineering properties can vary widely from place to place – even within the confines of a single construction project. Geotechnical engineering practice is devoted to the location of various soils encountered on a project, the determination of their engineering properties, correlating those properties to the project requirements, and the selection of the best available soils for use with the various structural elements of the project. -
Soil Mechanics Lectures Third Year Students
2016 -2017 Soil Mechanics Lectures Third Year Students Includes: Stresses within the soil, consolidation theory, settlement and degree of consolidation, shear strength of soil, earth pressure on retaining structure.: Soil Mechanics Lectures /Coarse 2-----------------------------2016-2017-------------------------------------------Third year Student 2 Soil Mechanics Lectures /Coarse 2-----------------------------2016-2017-------------------------------------------Third year Student 3 Soil Mechanics Lectures /Coarse 2-----------------------------2016-2017-------------------------------------------Third year Student Stresses within the soil Stresses within the soil: Types of stresses: 1- Geostatic stress: Sub Surface Stresses cause by mass of soil a- Vertical stress = b- Horizontal Stress 1 ∑ ℎ = ͤͅ 1 Note : Geostatic stresses increased lineraly with depth. 2- Stresses due to surface loading : a- Infintly loaded area (filling) b- Point load(concentrated load) c- Circular loaded area. d- Rectangular loaded area. Introduction: At a point within a soil mass, stresses will be developed as a result of the soil lying above the point (Geostatic stress) and by any structure or other loading imposed into that soil mass. 1- stresses due Geostatic soil mass (Geostatic stress) 1 = ℎ , where : is the coefficient of earth pressure at # = ͤ͟ 1 ͤ͟ rest. 4 Soil Mechanics Lectures /Coarse 2-----------------------------2016-2017-------------------------------------------Third year Student EFFECTIVESTRESS CONCEPT: In saturated soils, the normal stress ( σ) at any point within the soil mass is shared by the soil grains and the water held within the pores. The component of the normal stress acting on the soil grains, is called effective stressor intergranular stress, and is generally denoted by σ'. The remainder, the normal stress acting on the pore water, is knows as pore water pressure or neutral stress, and is denoted by u. -
Study on the Mechanism of Loess Landslide Induced by Chlorine Salt in Heifangtai Terran
Japanese Geotechnical Society Special Publication 7th Asia-Pacific Conference on Unsaturated Soils (AP-UNSAT2019) Study on the mechanism of loess landslide induced by chlorine salt in Heifangtai terran Juan Wang i ,ii), Wei Liu i ,ii), Wenwu Chen i ,ii), Peng Liu i ,ii) , Bobo Jia i ,ii), He Xu i ,ii) , Li Wen iii) i) Department of Geological Engineering, Lanzhou University, Tianshui Road, 222, Lanzhou 730000, China ii) Key Laboratory of Mechanics on Disaster and Environment in Western China, Ministry of Education, China iii) School of Information Science and Technology, Lanzhou University, Lanzhou 730000,China ABSTRACT It is well known that water content is the key factor affecting the loess strength. In arid and semi-arid regions, the salt content in pore solution of loess is relatively high. Rainfall or irrigation can change the water content of loess and induce geological disasters such as loess landslide and loess mud flow. In this paper, Heifangtai, Gansu Province, is chosen as the study site, where is the most typical place of loess landslides. The occurrence of loess landslides is closely related to water, salt. In order to investigate the interaction rules of these three factors, a series of pressure plate apparatus tests and undrained shear tests were conducted on saturated loess, to investigate the degradation mechanism of loess strength caused by the interaction between water and salt.The results showed that: NaCl concentration had a significant effect on the matrix suction, i.e. the water retention capacity of loess sample increased as the increase of NaCl concentration,especially in the boundary effect zone (low suction zone, soil almost saturated), concerning the remolded loess samples having a same dry density.The increase of NaCl concentration in pore water can also lead to the decrease of shear strength of saturated loess, especially for the cohesion. -
MREI 12-01 – Geotechnical Guidelines for Sample Handling, Testing and Data Reporting
MREI 12-01 – Geotechnical Guidelines for Sample Handling, Testing and Data Reporting VTrans Materials & Research Engineering Instructions MREI 12-01 Distribution: Structures, Director PDD, Assistant Director PDD, PDD Section Managers, Chief of Contract Admin., Director Ops., Assistant Director Ops., Consultants. Approved: Date: 12-27-2012 William E. Ahearn, Materials and Research Engineer Subject: Geotechnical Guidelines to Standardize VTrans’ Sample Handling, Testing and Data Reporting Procedures Administrative Information: Effective Date: This Materials & Research Engineering Instruction (MREI) shall be considered effective from the date of approval. Superseded MREI: None Disposition of MREI Content: The content of this MREI will be incorporated into a future VTrans Soils & Foundations Engineering Manual. 1. PURPOSE: The purpose of this MREI is to standardize Geotechnical sample handling, testing and data reporting procedures performed at the Vermont Agency of Transportation, Materials & Research Laboratory. 2. TECHNICAL INFORMATION: In general, guidance outlined in Sections 9.0 and 10.0 of AASHTO Manual of Subsurface Investigations, 1988 and Section 4.12.2 of FHWA’s Geotechnical Engineering Circular No. 5, GEC No. 5 shall be followed. Any specific guidance presented in this MREI that differs from these references shall take precedence. Page 1 of 20 MREI 12-01 – Geotechnical Guidelines for Sample Handling, Testing and Data Reporting 3. OVERVIEW: Handling of geotechnical samples from field to laboratory can be critical to the integrity of the material to be tested. Proper handling methods are addressed to assure the material to be tested yields meaningful and representative data. The means of identifying and tracking materials to be tested are identified allowing for a traceable record for each sample. -
Hydrologic Processes in Vertisols
the united nations educational, scientific abdus salam and cultural organization international centre for theoretical physics ternational atomic energy agency H4.SMR/1304-11 "COLLEGE ON SOIL PHYSICS" 12 March - 6 April 2001 Hydrologic Processes in Vertisols M. Kutilek and D. R. Nielsen Elsevier Soil and Tillage Research (Journal) Prague Czech Republic These notes are for internal distribution onlv strada costiera, I I - 34014 trieste italy - tel.+39 04022401 I I fax +39 040224163 - [email protected] - www.ictp.trieste.it College on Soil Physics ICTP, TRIESTE, 12-29 March, 2001 LECTURE NOTES Hydrologic Processes in Vertisols Extended text of the paper M. Kutilek, 1996. Water Relation and Water Management of Vertisols, In: Vertisols and Technologies for Their Management, Ed. N. Ahmad and A. Mermout, Elsevier, pp. 201-230. Miroslav Kutilek Professor Emeritus Nad Patankou 34, 160 00 Prague 6, Czech Republic Fax/Tel +420 2 311 6338 E-mail: [email protected] Developments in Soil Science 24 VERTISOLS AND TECHNOLOGIES FOR THEIR MANAGEMENT Edited by N. AHMAD The University of the West Indies, Faculty of Agriculture, Depart, of Soil Science, St. Augustine, Trinidad, West Indies A. MERMUT University of Saskatchewan, Saskatoon, sasks. S7N0W0, Canada ELSEVIER Amsterdam — Lausanne — New York — Oxford — Shannon — Tokyo 1996 43 Chapter 2 PEDOGENESIS A.R. MERMUT, E. PADMANABHAM, H. ESWARAN and G.S. DASOG 2.1. INTRODUCTION The genesis of Vertisols is strongly influenced by soil movement (contraction and expansion of the soil mass) and the churning (turbation) of the soil materials. The name of Vertisol is derived from Latin "vertere" meaning to turn or invert, thus limiting the development of classical soil horizons (Ahmad, 1983).