Author: Publisher: ISBN: Category : Columns, Concrete Languages : en Pages :
Book Description
"Mechanically stabilized earth (MSE) walls are an inexpensive and aesthetically attractive means of retaining soil. While the design principles for MSE structures have been accepted for several decades, space restrictions at MSE wall sites have led to new demands on MSE wall structures to support laterally loaded deep foundation elements constructed within the reinforced mass. Current design procedures for such configurations are by necessity based on very conservative design assumptions due to the lack of test data. This report contains estimates of the capacity of concrete columns, commonly referred to as drilled shafts, constructed behind the facing of a mechanically stabilized earth wall within the reinforced mass. This is the first of two reports on this topic and contains design capacity recommendations for 36 inch diameter shafts constructed behind an MSE wall with a height of 20 feet based on full scale field testing. It also contains recommendations for P-Y curve analyses for similar wall-shaft configurations. These recommendations and a discussion of their development were prepared by Dan Brown and Associates and are presented in Appendix B. The second report will contain capacity recommendations for walls and shafts with a range of heights and diameters based on computer models calibrated with the field data reported herein. A 20 foot tall, 140 foot long MSE block wall was built in accordance with AASHTO and KDOT specifications using the Mesa system developed by Tensar International. The wall supported eight 36 inch diameter vertical shafts constructed at four different distances from the back of the facing to the center of the shaft. These shafts were then loaded toward the wall facing using a displacement control method. The shafts and wall were monitored using multiple methods as each shaft was loaded to failure. Shafts were determined to have substantial lateral capacity, with capacity and width of shaft influence increasing as the distance of the shaft from the wall increased. The wall facing was very effective at concealing large deformations. Cracks appeared at the back of the reinforcement, suggesting that additional capacity may be achieved by lengthening the reinforcement. Recommendations for design lateral shaft capacities based on ultimate shaft load and on allowable deformations are presented in Chapter Five of this report"--Technical report documentation page.
Author: Awdhesh Kumar Choudhary Publisher: Springer Nature ISBN: 981161993X Category : Science Languages : en Pages : 335
Book Description
This book presents select proceedings of the National conference on Geo-Science and Geo-Structures (GSGS 2020). It provides sustainable solutions to various challenges encountered in the field of geotechnical engineering. The topics presented include advanced characterization to study the behavior of geomaterials, shallow and deep foundations including tunneling, use of geosynthetics and other soil reinforcing materials in minimizing slope failures and landslides, dynamics of soils and foundations, and its connection with energy geotechnics, transportation geotechnics, and offshore geotechnics. The book further highlights various aspects of ground improvement techniques by incorporating the use of industrial by-products, forensic analyses of geo-structures, instrumentation and sensing techniques in geotechnical engineering and issues associated with geo-environmental engineering. The book will be a valuable reference for budding researchers, academicians, practitioners and policymakers interested in sustainable practices associated with geotechnical engineering and related domains.
Author: Md. Saidur Rahman Publisher: ISBN: Category : Languages : en Pages : 282
Book Description
Currently there is no design guideline to consider the interaction between Mechanically Stabilized Earth (MSE) wall and the drilled shafts constructed inside the MSE wall under cyclic loading. The behaviors of the MSE wall and the drilled shafts under cyclic loading are important because the deformation of MSE wall and capacity of the drilled shaft under cyclic loading may be significantly different from these under static loading. This study encompasses a numerical study which investigates the influence of various factors on interaction between the MSE wall and the drilled shaft that is subjected to cyclic loading. The three-dimensional (3D) finite difference software, FLAC3D, is utilized in this study for the numerical analysis. A numerical model of a MSE wall is developed and calibrated using full-scale field test data. Thereafter a parametric study has been performed to investigate the influence of different factors on the interaction between the MSE wall and the drilled shaft that is subjected to cyclic loading. The investigated factors include backfill friction angle, backfill soil modulus, geogrid stiffness, cyclic loading magnitude, shaft length, and location of drilled shaft. The impact of those factors on lateral deflection in drilled shaft, horizontal and vertical deflections of MSE wall, lateral earth pressure, and stress and strain in geogrid is evaluated due to cyclic loading on the drilled shaft. The overall drilled shaft and MSE wall lateral deflection increases at all the parametric studies under cyclic loading. From the details parametric study results it can be concluded that the increase of tension and strain in geogrid varies at different elevations. The maximum geogrid tension and strain is found at 5.9 m elevation. The increase of lateral earth pressure also changes with the change of elevation. The maximum lateral earth pressure increase is found at 5.1 m elevation for all parametric study.
Author: J.-L. Briaud Publisher: ISBN: Category : Reinforced soils Languages : en Pages : 184
Book Description
Drilled shafts are being constructed within the reinforced zone of mechanically stabilized earth (MSE) walls especially in the case of overpass bridges where the drilled shafts carry the bridge deck or traffic signs. The interaction between the drilled shaft and the MSE wall is not well known and not typically incorporated into the design. As part of the research project, a full-scale test was conducted in 2012 at Texas A&M University. The test was performed on an MSE wall where the backfill material was clean sand and the soil reinforcement was made of metal strips. Also two real projects w ere instrumented during construction, and data were gathered for one year. A numerical model was used and calibrated against the results of the three full-scale cases. Then a sensitivity analysis was performed and 64 numerical cases were modeled to understand the effect of different parameters on the interaction between the MSE wall and the drilled shaft. The data from the simulations, the full-scale test results, and the monitoring of the real site were processed, and a modification of the current guidelines was proposed for the case where there is a drilled shaft subjected to a horizontal load in the reinforced zone of the MSE wall. A design chart is presented to take into account the addidtional pressure on the wall created by the drilled shaft.
Author: Lymon C. Reese Publisher: ISBN: Category : Shafts (Excavations) Languages : en Pages : 244
Book Description
Drilled shafts have been used on a limited scale for many years as an alternative to driven piles in a variety of foundation problems. However, uncertainty about the behavior of the drilled shaft has forestalled widespread adoption. The subject package, by Dr. Lymon C. Reese of the University of Texas, is intended for use by bridge engineers, geotechnical engineers, and builders of pile foundations. The manual contains rational procedures and practical guidelines for the design and construction of drilled shaft foundations. Volume I presents a rational design procedure for drilled shafts under axial loading and includes guidelines on construction methods, inspection, load testing, specifications, and cost estimates. Volume II presents alternative methods for computing the response of the shaft to lateral loading and presents the structural design of the shaft for axial and/or lateral loading.
Author: Lymon C. Reese Publisher: ISBN: Category : Shafts (Excavations) Languages : en Pages : 152
Book Description
Drilled shafts have been used on a limited scale for many years as an alternative to driven piles in a variety of foundation problems. However, uncertainty about the behavior of the drilled shaft has forestalled widespread adoption. The subject package, by Dr. Lymon C. Reese of the University of Texas, is intended for use by bridge engineers, geotechnical engineers, and builders of pile foundations. The manual contains rational procedures and practical guidelines for the design and construction of drilled shaft foundations. Volume I presents a rational design procedure for drilled shafts under axial loading and includes guidelines on construction methods, inspection, load testing, specifications, and cost estimates. Volume II presents alternative methods for computing the response of the shaft to lateral loading and presents the structural design of the shaft for axial and/or lateral loading.
Author: Christopher L. Meehan Publisher: ISBN: 9780784412787 Category : Civil engineering Languages : en Pages : 2280
Book Description
This Geotechnical Special Publication contains 229 peer-reviewed technical papers and case studies focusing on the stability, performance, and rehabilitation of slopes, embankments, and dams. Topics include: exploration and characterisation of soil and rock slopesdesign, analysis, and performance of slopesmonitoring and inspection of slopeshazard assessment and managementground improvement and stabilisation in the repair and remediation of slopes. These papers are valuable to geotechnical researchers and practicing engineers, especially those interested in the design and maintenance of slopes, embankments and dams.
Author: 
Author: Awdhesh Kumar Choudhary
Author: Md. Saidur Rahman
Author: J.-L. Briaud
Author: Lymon C. Reese
Author: Lymon C. Reese
Author: Albert Chi Fu To
Author: Lymon C. Reese
Author: P. W. Mayne
Author: Christopher L. Meehan