This report develops and calibrates procedures and modifies the AASHTO LRFD Bridge Design Specifications, Section 10-Foundations for the Strength Limit State Design of Shallow Foundations. The material in this report will be of immediate interest to bridge engineers and geotechnical engineers involved in the design of shallow foundations.
Introduction and research approach -- Findings -- Interpretation, appraisal, and applications -- Conclusions and suggested research -- Bibliography -- Appendixes.
The ground is one of the most highly variable of engineering materials. It is therefore not surprising that geotechnical designs depend on local site conditions and local engineering experience. Engineering practices, relating to investigation and design methods site understanding and to safety levels acceptable to society, will therefore vary between different regions.The challenge in geotechnical engineering is to make use of worldwide geotechnical experience, established over many years, to aid in the development and harmonization of geotechnical design codes. Given the significant uncertainties involved, empiricism and engineering
Model Uncertainties in Foundation Design is unique in the compilation of the largest and the most diverse load test databases to date, covering many foundation types (shallow foundations, spudcans, driven piles, drilled shafts, rock sockets and helical piles) and a wide range of ground conditions (soil to soft rock). All databases with names prefixed by NUS are available upon request. This book presents a comprehensive evaluation of the model factor mean (bias) and coefficient of variation (COV) for ultimate and serviceability limit state based on these databases. These statistics can be used directly for AASHTO LRFD calibration. Besides load test databases, performance databases for other geo-structures and their model factor statistics are provided. Based on this extensive literature survey, a practical three-tier scheme for classifying the model uncertainty of geo-structures according to the model factor mean and COV is proposed. This empirically grounded scheme can underpin the calibration of resistance factors as a function of the degree of understanding – a concept already adopted in the Canadian Highway Bridge Design Code and being considered for the new draft for Eurocode 7 Part 1 (EN 1997-1:202x). The helical pile research in Chapter 7 was recognised by the 2020 ASCE Norman Medal.
This book presents articles covering a wide spectrum of topics in geotechnical engineering, including properties of soils, unsaturated soil mechanics, ground improvement, liquefaction and seismic studies, soil-structure interaction and stability analysis of man-made and natural slopes. The contributing authors are renowned researchers in their respective fields, which include soft ground improvement, seismic response of retaining structure using soil-structure Interaction (SSI) principles, and unsaturated soils. Based on keynote addresses and invited talks presented at the Indian Geotechnical Conference 2016, this book will prove a valuable resource for practicing engineers and researchers in the field of geotechnical engineering.
This is the first book to revisit geotechnical site characterization from a probabilistic point of view and provide rational tools to probabilistically characterize geotechnical properties and underground stratigraphy using limited information obtained from a specific site. This book not only provides new probabilistic approaches for geotechnical site characterization and slope stability analysis, but also tackles the difficulties in practical implementation of these approaches. In addition, this book also develops efficient Monte Carlo simulation approaches for slope stability analysis and implements these approaches in a commonly available spreadsheet environment. These approaches and the software package are readily available to geotechnical practitioners and alleviate them from reliability computational algorithms. The readers will find useful information for a non-specialist to determine project-specific statistics of geotechnical properties and to perform probabilistic analysis of slope stability.
This report contains proposed specifications for the design and construction of soil-nailed retaining structures. Despite their advantages in cut applications, these structures are not available to some state DOTs, due to the lack of guidance for their use in AASHTO's standard specifications based on load and resistance factor design (LRFD).
Communication of risks within a transparent and accountable framework is essential in view of increasing mobility and the complexity of the modern society and the field of geotechnical engineering does not form an exception. As a result, modern risk assessment and management are required in all aspects of geotechnical issues, such as planning, desi
Written to Eurocode 7 and the UK National Annex Updated to reflect the current usage of Eurocode 7, along with relevant parts of the British Standards, Pile Design and Construction Practice, Sixth Edition maintains the empirical correlations of the original—combining practical know how with scientific knowledge —and emphasizing relevant principles and applications of soil mechanics and design. Contractors, geotechnical engineers and engineering geologists responsible for designing and constructing piled foundations can find the most current types of pile, piling equipment, and relevant methods in this latest work. The book summarizes recent changes, including new codified design procedures addressing design parameters and partial safety factors. It also presents several examples, many based on actual problems. Broad and Comprehensive In Its Coverage Contains material applicable to modern computational practice Provides new sections on the construction of micropiles and CFA piles, pile-soil interaction, verification of pile materials, piling for integral bridge abutments, use of polymer stabilising fluids, and more Includes calculations of the resistance of piles to compressive loads, pile groups under compressive loading, piled foundations for resisting uplift and lateral loading, and the structural design of piles and pile groups Covers marine structures, durability of piled foundations, ground investigations, and pile testing Addresses miscellaneous problems such as machinery foundations, underpinning, mining subsidence areas, geothermal piles, and unexploded ordnance Pile Design and Construction Practice, Sixth Edition serves as a comprehensive guide for practicing geotechnical engineers and engineering geologists. This text also works as a resource for piling contractors and graduate students studying geotechnical engineering.
