Forensic Analyses and Rehabilitation of a Failed Highway Embankment Slope in Texas

2021 ◽  
pp. 036119812199635
Author(s):  
Burak Boluk ◽  
Anand J. Puppala ◽  
Sayantan Chakraborty ◽  
Puneet Bhaskar
Keyword(s):  
Mechanical Properties ◽  
Laboratory Tests ◽  
Slope Failure ◽  
Engineering Properties ◽  
High Plasticity ◽  
Slope Failures ◽  
Lime Treatment ◽  
Embankment Slope ◽  
The Stability ◽  
Highway Embankment

A comprehensive investigation was designed and conducted to identify the potential causes of failure of a highway embankment slope in Texas and evaluate the effectiveness of lime treatment to rehabilitate the failed slope. Highway slopes built with high plasticity clays often experience shallow slope failures after exposure to repeated wet–dry weathering cycles. Lime stabilization generally reduces the swell–shrink potential, enhances the engineering properties of problematic clayey soils, and can potentially prevent surficial slope failures. However, exposure to wet–dry cycles can negate some of the benefits of lime treatment and therefore a study was conducted to address the use of this lime treatment to stabilize embankment slopes. Extensive laboratory tests were conducted to study the effect of weathering cycles on the degradation of hydro-mechanical properties of untreated and lime-treated soils. Rainfall-induced slope stability analyses were performed to investigate the probable causes of slope failure and evaluate the stability of lime-treated surficial slope. The optimum stabilizer dosage and treated layer thickness required for the slope rehabilitation were determined based on laboratory tests and numerical analysis results. The stability analysis results indicate that the degradation of surficial soil’s hydro-mechanical properties and the development of a perched water table during prolonged rainfall possibly caused the slope failure. The post-treatment increase in shear strength properties, reduction in moisture fluctuations recorded by embedded moisture sensors, and the presence of newly installed underlying drains are expected to prevent recurrence of surficial slope failures. Salient results from this study are covered in this paper.

scholarly journals The Alternatives to Traditional Materials for Subsoil Stabilization and Embankments

Materials ◽  
2019 ◽  
Vol 12 (18) ◽  
pp. 3018 ◽  
Author(s):  
Mirjana Vukićević ◽  
Miloš Marjanović ◽  
Veljko Pujević ◽  
Sanja Jocković
Keyword(s):  
Mechanical Properties ◽  
Fly Ash ◽  
Power Plants ◽  
Soil Stabilization ◽  
Soft Soil ◽  
Physical And Mechanical Properties ◽  
Engineering Properties ◽  
High Plasticity ◽  
Natural Materials ◽  
Positive Effects

Major infrastructure projects require significant amount of natural materials, often followed by the soft soil stabilization using hydraulic binders. This paper presents the results of a laboratory study of alternative waste materials (fly ash and slag) that can be used for earthworks. Results of high plasticity clay stabilization using fly ash from Serbian power plants are presented in the first part. In the second part of the paper, engineering properties of ash and ash-slag mixtures are discussed with the emphasis on the application in road subgrade and embankment construction. Physical and mechanical properties were determined via following laboratory tests: Specific gravity, grain size distribution, the moisture–density relationship (Proctor compaction test), unconfined compressive strength (UCS), oedometer and swell tests, direct shear and the California bearing ratio (CBR). The results indicate the positive effects of the clay stabilization using fly ash, in terms of increasing strength and stiffness and reducing expansivity. Fly ashes and ash-slag mixtures have also comparable mechanical properties with sands, which in combination with multiple other benefits (lower energy consumption and CO2 emission, saving of natural materials and smaller waste landfill areas), make them suitable fill materials for embankments, especially considering the necessity for sustainable development.

scholarly journals Analysis on Physical and Mechanical Properties of Red Mud Materials and Stockpile Stability after Dilatation

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Yanbo Feng ◽  
Chao Yang
Keyword(s):  
Mechanical Properties ◽  
Red Mud ◽  
Capital Investment ◽  
Physical And Mechanical Properties ◽  
Dam Break ◽  
Engineering Properties ◽  
Drying Process ◽  
Bayer Red Mud ◽  
The Stability ◽  
Wetting Process

Red mud is the tailings generated from the production process of aluminum industry and is mainly stacked in open-air at present, so how to ensure the stability of red mud stockpile is very important. Regarding mud stockpile of Guizhou Aluminum Factory as the research object, this paper studies the physical and mechanical properties of Bayer red mud from wetting process, Bayer red mud from drying process, and sintering red mud through laboratory test and finally analyzes its stability under extreme rainfall condition in this region by the Geo-Studio software. The research results show that the red muds in different processes have big difference in physical and mechanical properties. The strength of sintering red mud is about 4.2 times of that of Bayer red mud from wetting process on average, and the strength of Bayer red mud from drying process is about 1.5 times of that of Bayer red mud from wetting process on average. So, the sintering red mud can be used as the subdam of red mud stockpile, to reduce the risk of collapse and dam break. The stability coefficients of the mixed stocking method under three rainfall conditions are 2.611, 2.597, and 2.631, respectively, all of which are above 1.0. It reveals that the dilatation scheme of using the sintering red mud with good engineering properties to stockpile the Bayer red mud is feasible. It can not only guarantee the safety and stability of red mud stockpiles, but also reduce the risk of red mud dam break and the capital investment of red mud yard.

Sand Soil Properties as the Sea Embankment Material Used in Pipe-Bag Riding Method

2012 ◽  
Vol 488-489 ◽  
pp. 1071-1075
Author(s):  
Xuan Zhang ◽  
Liang De He ◽  
Ning Zhuang
Keyword(s):  
Stability Analysis ◽  
Laboratory Tests ◽  
Grain Shape ◽  
Construction Material ◽  
Sand Soil ◽  
Liquefaction Potential ◽  
Shape Coefficient ◽  
Embankment Slope ◽  
Coefficient Of Permeability ◽  
The Stability

Comparing with the stability demands of construction material used in pipe-bag riding technology for sea embankments, and based on many site and laboratory tests of sand distributed in Dongtai offshore, Northern Jiangsu Province in China for reclamation engineering, the type of sand, mechanical composition, grain shape, coefficient of permeability and liquefaction potential of sands were discussed. Additionally, the sea embankment slope stability analysis and seepage stability analysis demonstrate the sands can be used in sea embankment construction for pipe bag method

scholarly journals Examining the Effects of Suction and Nonlinear Strength Envelopes on the Stability of a High Plasticity Clay Slope

Geosciences ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 449
Author(s):  
Mengwei Xuan ◽  
Jack Montgomery ◽  
J. Brian Anderson
Keyword(s):  
Limit Equilibrium ◽  
Friction Angle ◽  
Stability Factor ◽  
High Plasticity ◽  
Slope Failures ◽  
Clay Deposits ◽  
Ring Shear ◽  
High Plasticity Clay ◽  
The Stability ◽  
Cut Slopes

Slope failures in high plasticity clay deposits are common occurrences in many parts of the world. In western and central Alabama, expansive Prairie clays are commonly found, and shallow slope failures have occurred in both fill and cut slopes containing these high plasticity clays. The objective of this study was to examine the effects of suction and the use of nonlinear strength envelopes on the embankment stability of a section of highway AL-5. The testing program consisted of fifteen ring shear tests performed using a Bromhead Ring Shear Device. The results of the tests were used to develop both linear and nonlinear fully softened and residual strength envelopes. The saturated strength envelopes are then used in a limit equilibrium slope stability analysis with and without the effects of suction. The results show stability (factor of safety >1) for all cases except the residual friction angle without suction. Given these results, large slope failures are unlikely to occur in this area, but surficial failures and deformations due to creep may be possible. These results demonstrate the importance of considering the effects of suction and nonlinear strength envelopes when examining the potential for shallow slope failures in high plasticity clays.

Mechanisms of massive failure for flowthrough rockfill embankments

1995 ◽  
Vol 32 (6) ◽  
pp. 927-938 ◽  
Author(s):  
Vinod K. Garga ◽  
David Hansen ◽  
D. Ronald Townsend
Keyword(s):  
Key Words ◽  
Failure Mechanism ◽  
Slope Failure ◽  
Darcy Flow ◽  
Experimental Measurements ◽  
Embankment Slope ◽  
Rockfill Dam ◽  
Downstream Slope ◽  
The Stability ◽  
Rotational Failure

A modified wedge method for the analysis of the stability of a downstream slope of a flowthrough rockfill dam is presented. The results from this wedge analysis are compared with results from a conventional Bishop method of analysis, and both are compared with experimental measurements of the forces at incipient failure from model tests performed on simple granular embankments in hydraulic flumes. The proposed wedge method, based on a nonrotational failure mechanism, compared more favourably with experimental observations than did the Bishop method of analysis, based on a rotational failure mechanism. It is also concluded that the Bishop method is very conservative for the analysis of such rockfill slopes. Key words : rockfill embankment, slope failure, bursting forces, model slopes, non-Darcy flow.

A Slope Failure in Swelling Clay

1973 ◽  
Vol 10 (3) ◽  
pp. 531-536 ◽  
Author(s):  
G. Kassiff ◽  
I. Alpan
Keyword(s):  
Shear Strength ◽  
Laboratory Tests ◽  
Slope Failure ◽  
Climatic Conditions ◽  
Expansive Clay ◽  
Bridge Abutment ◽  
Actual Field ◽  
The Stability ◽  
Short Time ◽  
Loss Of Strength

A recent heavy rainy season in the semiarid climatic conditions of northern and central Israel caused a number of slope failures of embankments and bridge abutments in expansive clay soils.Failure of a 9 m high slope of a bridge abutment is reported. The failure occurred owing to migration of moisture into the clay a short time after the slope was completed. Soil characteristics such as plasticity, swelling potential, and shear strength are presented and discussed. The stability of the slope was analyzed using Taylor's chart and strength parameters obtained from laboratory tests. It is concluded that failure occurred owing to substantial loss of strength following swelling of the clay. Results of laboratory tests for shear strength after saturation and swelling seem to correlate well with actual field conditions in this case.

scholarly journals Field and laboratory investigation of rainfall-triggered slope failure in unsaturated loess soils, New Zealand

2020 ◽  
Vol 195 ◽  
pp. 01017
Author(s):  
Katherine Yates ◽  
Adrian Russell ◽  
Clark Fentonl
Keyword(s):  
New Zealand ◽  
Slope Failure ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Slope Failures ◽  
Residential Housing ◽  
The Stability ◽  
Unsaturated Loess ◽  
Pressure Suction

Shallow rainfall triggered slope failures occur frequently in loess and loess-derived deposits across the South Island, New Zealand. These failures, which occur in both natural slopes and engineered cuttings, impact road infrastructure, residential housing and rural land use. When dry, the loess can form near vertical cuttings. However, with increase in moisture content loess slopes become susceptible to shallow slope failures. To date, the influence of negative pore-water pressure (suction) on the stability of loess slopes in New Zealand has not been well understood. In this paper, data from long term in situ field monitoring of rainfall, suction and volumetric water content from a loess slope in Banks Peninsula, Canterbury are presented with laboratory triaxial test results undertaken on undisturbed unsaturated loess samples. Field and laboratory soil responses to wetting and drying are compared, and the characteristics of rainfall events which reduce suction in situ and therefore slope stability are discussed.

scholarly journals Tropical Residual Soil Properties on Slopes

2017 ◽  
Vol 4 (2) ◽  
pp. 139-147
Author(s):  
M.F. Ishak ◽  
M.F. Zolkepli ◽  
M. Affendy
Keyword(s):  
Chemical Weathering ◽  
Slope Failure ◽  
Engineering Properties ◽  
Tropical Region ◽  
High Plasticity ◽  
Residual Soil ◽  
Residual Properties ◽  
The World ◽  
Parent Rocks ◽  
Properties Of Soil

Tropical residual soil is a product of chemical weathering, thus its characteristics are dependent upon environmental factors such as parent rocks, climate, topography and age. This type of soil can be found in many countries all over the world, especially in the tropical region. Since there are many accident happens due to slope failure, a comprehensive laboratory study need to be conducted in order to determine the properties of soil located at Pahang Matriculation College. Several experiments involving physical index and engineering properties of soil are conducted. The typical tropical residual properties are showed and can be considered as sandy SILT of high plasticity.

Evaluating the Long-Term Durability of Lime Treatment in Hydraulic Structures: Case Study on the Friant-Kern Canal

2020 ◽  
Vol 2674 (6) ◽  
pp. 431-443 ◽  
Author(s):  
Pavan Akula ◽  
Narain Hariharan ◽  
Dallas N. Little ◽  
Didier Lesueur ◽  
Gontran Herrier
Keyword(s):  
Slope Failure ◽  
Fluorescence Analysis ◽  
Engineering Properties ◽  
Hydraulic Structures ◽  
Lime Treatment ◽  
Geochemical Model ◽  
Bureau Of Reclamation ◽  
Tenfold Increase ◽  
Geochemical Reactions

The slopes along the Friant-Kern Canal were last treated in the 1970s with 4% quick lime to mitigate issues related to slope failure caused by expansive Porterville soils. The immediate benefits of lime treatment were well documented by the Bureau of Reclamation. However, questions remain over the long-term durability of lime-treated materials. In this study, we compare the engineering properties and changes in the soil mineralogy of treated and untreated sections to establish the effectiveness of lime after more than 40 years of performance. A geochemical model was developed using the GEM-Selektor program to simulate the geochemical reactions in the soil-lime system and predict stable pozzolanic products. The experimental results show a reduction in the plasticity index from 23 to 6 after lime treatment together with a tenfold increase in strength. Lime addition lowers the risk of volumetric expansion and erosion in soils from moderately high to very low. Further, a pH increase from 6.30 to 8.90 in lime-treated sections indicates that lime treatment continues to be effective. X-ray fluorescence analysis shows the presence of Ca2+ ions in quantities similar to the initial treatment dosage indicating negligible leaching of lime. The geochemical model provides evidence of the formation of pozzolanic products in the soil-lime system which was validated using thermogravimetry analysis. The performance history of the Friant-Kern Canal together with the findings of this study affirm the long-term durability of lime treatment on this project and strengthens the case for using lime in the repair of hydraulic structures.

Field and laboratory behaviour of fine-grained soil stabilized with lime

2020 ◽  
Vol 57 (6) ◽  
pp. 933-938
Author(s):  
Nilo Cesar Consoli ◽  
Eduardo José Bittar Marin ◽  
Rubén Alejandro Quiñónez Samaniego ◽  
Hugo Carlos Scheuermann Filho ◽  
Nuno Miguel Cordeiro Cristelo
Keyword(s):  
Mechanical Properties ◽  
Laboratory Tests ◽  
Clayey Soil ◽  
Hydrated Lime ◽  
High Plasticity ◽  
Maintenance Costs ◽  
Fine Grained ◽  
Fine Grained Soil ◽  
First Time ◽  
Effective Procedures

Fine-grained soils, due to their high plasticity, possess great shrinkage potential and high compressibility and are responsible for very substantial maintenance costs during the service life of the associated infrastructures. Stabilization of such soils with lime is one of the most effective procedures to mitigate these undesirable characteristics and, at the same time, to enhance their mechanical properties. Current research seeks, through field and laboratory tests, to quantify the influence of calcitic hydrated lime on the strength and deflection characteristics clayey soil from the Paraguayan region of Chaco. The influence of different dry unit weights, lime amounts, and curing periods on the strength and deflection of a Paraguayan clay stabilized with lime was assessed. The present work shows, for the first time ever, that the porosity/lime index is the proper parameter to be used in the field when dealing with the strength of clay–lime bases of pavements. Hence, the results presented herein are a contribution to understanding the conditions in which these soils can be stabilized to be used in infrastructural applications.

Sign in / Sign up

Export Citation Format

Share Document