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Book Development of Load and Resistance Factor Design Procedures for Driven Piles on Solf Rocks in Wyoming

Download or read book Development of Load and Resistance Factor Design Procedures for Driven Piles on Solf Rocks in Wyoming written by University of Wyoming. Department of Civil and Architectural Engineering and published by . This book was released on 2019 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The overall goal of the research project is to develop locally calibrated LRFD procedures (i.e., design methodologies and resistance factors) for driven piles on soft rocks in Wyoming." -- page 3.

Book Model Uncertainties in Foundation Design

Download or read book Model Uncertainties in Foundation Design written by Chong Tang and published by CRC Press. This book was released on 2021-03-16 with total page 589 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Book Load and Resistance Factor Design and Construction Control of Driven Piles in Intermediate Geomaterials

Download or read book Load and Resistance Factor Design and Construction Control of Driven Piles in Intermediate Geomaterials written by Pramila Adhikari and published by . This book was released on 2019 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Static Analysis methods originally developed for soils are currently used for estimating pile resistances in Intermediate Geomaterials (IGMs), and structural capacity has been considered as the limiting pile capacity on hard rocks. The application of current Load and Resistance Factor Design (LRFD) for piles in IGMs has resulted in relatively high uncertainties in pile resistance estimation during design and the length to which the piles are driven into IGMs during construction. Moreover, the absence of standard criteria to differentiate the geomaterials creates challenges in the design and construction of driven piles in IGMs. The application of a dynamic analysis method using Wave Equation Analysis Program is constrained by geomaterial input for IGMs and rocks. These current challenges have led to conservative pile resistance estimations. Thus, the overall objectives of this study were to determine efficient static analysis methods, dynamic procedures for construction control, pile setup/relaxation, and resistance factors for the estimation of the axial pile resistances in IGMs, ensuring a prescribed level of reliability to meet LRFD philosophy. To accomplish these objectives, classification criteria of geomaterials were first created to establish a standard quantitative delineation between the soils, IGMs, and hard rocks for the design of driven piles. In addition, a catalog of IGM properties was prepared to facilitate the preliminary design of piles in IGMs. Secondly, a new set of design equations were developed and validated for IGMs by utilizing the developed geomaterial classification criteria. Thirdly, wave equation analysis procedures for IGMs were recommended for pile construction control. Fourthly, changes in pile resistances in IGMs with respect to time at an End of Driving and Beginning of Restrike were assessed. Finally, probability based resistance factors were calibrated and recommended based on the efficiency factors for the existing and calibrated static analysis methods. Calibrated static analysis methods were concluded to have higher efficiency factors of 0.61, 0.30, and 0.41 against efficiency factors of 0.28, 0.09, and 0.14 corresponding to existing static analysis methods for shaft resistance estimation in IGMs. Similarly, calibrated static analysis methods were concluded to have higher efficiency factors of 0.24 and 0.48 against efficiency factors of 0.13 and 0.29 corresponding to existing static analysis methods for end bearing estimation in IGMs.

Book Load and Resistance Factor Design LRFD Pile Driving Project Phase II Study

Download or read book Load and Resistance Factor Design LRFD Pile Driving Project Phase II Study written by Aaron S. Budge and published by . This book was released on 2014 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt: Driven piles are the most common foundation solution used in bridge construction (Paikowsky et al., 2004). Their safe use requires to reliable verification of their capacity and integrity. Dynamic analyses of driven piles are methods attempting to obtain the static capacity of a pile, utilizing its behavior during driving. Dynamic equations (aka pile driving formulas) are the earliest and simplest forms of dynamic analyses. The development and the examination of such equation tailored for MnDOT demands is presented. In phase I of the study reported by Paikowsky et al. (2009, databases were utilized to investigate previous MnDOT (and other) dynamic formulas and use object oriented programming for linear regression to develop a new formula that was then calibrated for LRFD methodology and evaluated for its performance. This report presents the findings of phase II of the study in which a comprehensive investigation of the Phase I findings were conducted. The studies lead to the development of dynamic formulae suitable for MnDOT foundation practices, its calibrated resistance factors and its application to concrete and timber piles. Phase II of the study also expanded on related issues associated with Wave Equation analyses and static load tests, assisting the MnDOT in establishing requirements and specifications.

Book Development of Resistance Factors for Axial Capacity of Driven Piles in North Carolina

Download or read book Development of Resistance Factors for Axial Capacity of Driven Piles in North Carolina written by Kyung Jun Kim and published by . This book was released on 2002 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Keywords: pile bearing capacity, load and resistance factor design, Vesic, Nordlund, Meyerhof, reliability analysis, FORM, MVFOSM, AFOSM, resistance factor calibration, pile driving analyzer, static load test, bias factor.

Book Development of Load and Resistance Factor Design for Ultimate and Serviceability Limit States of Transportation Structure Foundations

Download or read book Development of Load and Resistance Factor Design for Ultimate and Serviceability Limit States of Transportation Structure Foundations written by Rodrigo Salgado and published by Purdue University Press. This book was released on 2011-10-12 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Most foundation solutions for transportation structures rely on deep foundations, often on pile foundations configured in a way most suitable to the problem at hand. Design of pile foundation solutions can best be pursued by clearly defining limit states and then configuring the piles in such a way as to prevent the attainment of these limit states. The present report develops methods for load and resistance factor design (LRFD) of piles, both nondisplacement and displacement piles, in sand and clay. With the exception of the method for design of displacement piles in sand, all the methods are based on rigorous theoretical mechanics solutions of the pile loading problem. In all cases, the uncertainty of the variables appearing in the problem and of the relationships linking these variables to the resistance calculated using these relationships are carefully assessed. Monte Carlo simulations using these relationships and the associated variabilities allow simulation of resistance minus load distributions and therefore probability of failure. The mean (or nominal) values of the variables can be adjusted so that the probability of failure can be made to match a target probability of failure. Since an infinite number of combinations of these means can be made to lead to the same target probability of failure, we have developed a way to determine the most likely ultimate limit state for a given probability of failure. Once the most likely ultimate limit state is determined, the values of loads and resistances for this limit state can be used, together with the values of the mean (or nominal) loads and resistances to calculate load and resistance factors. The last step in the process involves adjusting the resistance factors so that they are consistent with the load factors specified by AASHTO. Recommended resistance factors are then given together with the design methods for which they were developed.

Book Load and Resistance Factor Design LRFD for Driven Piles Using Dynamic Methods A Florida Perspective

Download or read book Load and Resistance Factor Design LRFD for Driven Piles Using Dynamic Methods A Florida Perspective written by MC. McVay and published by . This book was released on 2000 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: The parameters for load and resistance factor design (LRFD) of driven piles using dynamic methods are presented based on a database of 218 pile cases in Florida. Eight dynamic methods were studied: ENR, modified ENR, FDOT, and Gates driving formulas, Case Analysis with Wave Analysis Program (CAPWAP), Case Method for Pile Driving Analyzer (PDA), Paikowsky's energy method, and Sakai's energy method. It was demonstrated that the modern methods based on wave mechanics, such as CAPWAP, PDA, and Paikowsky's energy methods, are roughly twice as cost effective to reach the target reliability indices of 2.0 to 2.5 (failure probability = 0.62 to 2.5%) as the ENR and modified ENR driving formulas. The Gates formula, when used separately on piles with Davisson capacities smaller or larger than 1779 kN, has an accuracy comparable to the modern methods. The utilizable measured Davisson capacity, defined as ?/? (ratio of resistance/mean capacity) obtained from testing at beginning of redrive (BOR), is only slightly larger than the end of drive (EOD) values. Furthermore, past practice with driving formulas reveals the existence of a large redundancy in pile groups against failure. The latter suggests the use of a lower relatively reliability target index, ?T = 2.0 (pf = 2.5%) for single pile design. Also, the utilizable measured Davisson capacity, ?/?, for all the dynamic methods studied, is quite similar to published values (Lai et al. 1995; Sidi 1985) for static estimates from in situ tests.

Book Development of LRFD Driven Pile Resistance Factor by First Order Second Moment Method in Alabama Soils

Download or read book Development of LRFD Driven Pile Resistance Factor by First Order Second Moment Method in Alabama Soils written by Elisa D. Prado Villegas and published by . This book was released on 2015 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book New Static Analysis Methods and Improved Wave Equation Analysis Program for Driven Piles in Intermediate Geomaterials with Load and Resistance Factor Design Recommendations

Download or read book New Static Analysis Methods and Improved Wave Equation Analysis Program for Driven Piles in Intermediate Geomaterials with Load and Resistance Factor Design Recommendations written by Harish Kumar Kalauni and published by . This book was released on 2021 with total page 221 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accurate and reliable methods to predict resistances of driven piles in intermediate geomaterials (IGMs) are essential for improving the economics of pile design and construction.However, static analysis methods for driven piles in IGMs are rarely available. Past experiences have suggested that estimating pile resistances in IGMs using the conventional static analysis methods for soils can lead to several problems regarding pile design and construction. Thus, this study aims to develop static analysis methods and Load and Resistance Factor Design (LRFD)resistance factors to facilitate the design of driven piles in claystone, sandstone, and mudstone. Moreover, Wave Equation Analysis Program (WEAP) has been widely used to determine drivability, predict static pile resistance, and assure the integrity of piles in soils. Assigning staticand dynamic properties of IGMs remains a challenge in WEAP, partly attributed to lack of reliablemethods for unit resistance predictions for driven piles in IGMs. The challenge is further exacerbated as the recommended Smith parameters were originally developed for piles in soils.Using 129 steel H- and pipe piles driven in IGMs, improved WEAP methods and newly calibrated LRFD resistance factors are recommended. These recommendations are based on proposed static analysis methods and back-calculated Smith parameters for IGMs. An additional 46 test pile data was used to validate the recommendations. Finally, the economic impact of these WEAPrecommendations on the design and construction control of driven piles in IGMs was studied,which confirmed the economic benefits of the proposed improved WEAP methods.

Book Development of LRFD Design Procedures for Bridge Piles in Iowa

Download or read book Development of LRFD Design Procedures for Bridge Piles in Iowa written by and published by . This book was released on 2011 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: In response to the mandate on Load and Resistance Factor Design (LRFD) implementations by the Federal Highway Administration on all new bridge projects initiated after October 1, 2007, the Iowa Highway Research Board sponsored these research projects to develop regional LRFD recommendations. The LRFD development was performed using the Iowa Department of Transportation Pile Load Test database. To increase the data points for LRFD development, develop LRFD recommendations for dynamic methods, and validate the results of LRFD calibration, 10 full-scale field tests on the most commonly used steel H-piles were conducted throughout Iowa. Detailed in situ soil investigations were carried out, push-in pressure cells were installed, and laboratory soil tests were performed. Pile responses during driving, at the end of driving, and at re-strikes were monitored using the Pile Driving Analyzer, following with the CAse Pile Wave Analysis Program analysis. The hammer blow counts were recorded for Wave Equation Analysis Program and dynamic formulas. Static load tests were performed and the pile capacities were determined based on the Davisson's criteria. The extensive experimental research studies generated important data for analytical and computational investigations. The SLT measured load-displacements were compared with the simulated results obtained using a model of the TZPILE program and using the modified borehole shear test method. Two analytical pile setup quantification methods, in terms of soil properties, were developed and validated. A new calibration procedure was developed to incorporate pile setup into LRFD.

Book Load and Resistance Factor Design for Driven Piles Based on Static Methods

Download or read book Load and Resistance Factor Design for Driven Piles Based on Static Methods written by Thai Nguyen and published by . This book was released on 2001 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Development and Implementation of the DIGGS Format to Perform LRFD Resistance Factor Calibration of Driven Concrete Piles in Florida

Download or read book Development and Implementation of the DIGGS Format to Perform LRFD Resistance Factor Calibration of Driven Concrete Piles in Florida written by Mark Anthony Styler and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: National Cooperative Highway Research Program (NCHRP) Report 507 demonstrates that the difference between FORM and FOSM resistance factor calibrations can be up to 15%. With some pile caps containing in excess of 25 piles, millions could be saved if this difference could be accounted for. Currently, the more conservative FOSM is used instead of designing for a specific probability of failure. This thesis explored the difference between FOSM and FORM using DIGGS, a newly developed standard for digitally storing geotechnical data. The DIGGS standard was developed and documented and a DIGGS file containing 62 prestressed concrete piles from the State of Florida was created. These piles were also analyzed with the Bridge Software Institute s FB-Deep program to predict Davission Failure limits. Resistance factors were then calculated using both FOSM and FORM for the Davission Limit using FB-Deep. The results found agreed with the NCHRP 507 with FORM resistance factor calibrations being 8% to 23% greater than FOSM. Following this, a corrected FOSM equation was derived which agrees with the FORM results. Using the modified FOSM equation resistance factors can be more accurately predicted. Designers should recognize that using the larger resistance factors results in a larger probability of failure, but more importantly it results in a known probability of failure.