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Development Of Lrfd Driven Pile Resistance Factor By First Order Second Moment Method In Alabama Soils
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Book Synopsis Development of LRFD Driven Pile Resistance Factor by First Order Second Moment Method in Alabama Soils by : Elisa D. Prado Villegas
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 Synopsis Development of Resistance Factors for Axial Capacity of Driven Piles in North Carolina by :
Download or read book Development of Resistance Factors for Axial Capacity of Driven Piles in North Carolina written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Resistance factors were developed in the framework of reliability theory for the Load and Resistance Factor Design (LRFD) of driven pile's axial capacity in North Carolina utilizing pile load test data available from the North Carolina Department of Transportation. A total of 140 Pile Driving Analyzer (PDA) data and 35 static load test data were compiled and grouped into different design categories based on four pile types and two geologic regions. Resistance statistics were evaluated for each design category in terms of bias factors. Bayesian updating was employed to improve the statistics of the resistance bias factors, which were derived from a limited number of pile load test data. Load statistics presented in the current AASHTO LRFD Bridge Design Specifications were used in the reliability analysis and the calibration of the resistance factors. Reliability analysis of the current NCDOT practice of pile foundation design was performed to evaluate the level of safety and to select the target reliability indices. Resistance factor calibration was performed for the three methods of static pile capacity analysis commonly used in the NCDOT: the Vesic, the Nordlund, and the Meyerhof methods. Two types of First Order Reliability Methods (Mean Value First Order Second Moment method and Advanced First Order Second Moment method) were employed for the reliability analysis and the calibration of the resistance factors. Recommended resistance factors are presented for the three methods of static pile capacity analysis and for seven different design categories of pile types and geologic regions. The resistance factors developed and recommended from this research are specific for the pile foundation design by the three static capacity analysis methods and for the distinct soil type of the geologic regions of North Carolina. The methodology of the resistance factor calibration developed from this research can be applied to the resistance factor calibration for other foundation.
Book Synopsis Reliability-based Design and Acceptance Protocol for Driven Piles by : Joseph Jabo
Download or read book Reliability-based Design and Acceptance Protocol for Driven Piles written by Joseph Jabo and published by . This book was released on 2014 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: The current use of the Arkansas Standard Specifications for Highway Construction Manuals (2003, 2014) for driven pile foundations faces various limitations which result in designs of questionable reliability. These specifications are based on the Allowable Stress Design method (ASD), cover a wide range of uncertainties, do not take into account pile and soil types, and were developed for general use. To overcome these challenges it is deemed necessary to develop a new design and acceptance protocol for driven piles. This new protocol incorporates locally calibrated RLFD resistance factors for accounting for local design and construction experiences and practices, as well as specific soil conditions and pile types. In that perspective, this dissertation focuses on the design and acceptance of driven pile foundations (predominately for bridge projects) using an LRFD protocol. A great deal of insight is gained into the factors that contribute to the performance of deep foundations by conducting an extensive literature review. The research assembled a relatively large database of pile load tests where both static and dynamic load testing was performed and sufficient soils information existed to perform static design calculations. A MATLAB® based program was developed to use the information contained in the database to compute resistance factors for driven piles using the First Order Second Moment Method (FOSM), Improved FOSM, the First Order Reliability Method (FORM), and Monte Carlo Simulations (MCS). The research also addressed a technique to update resistance factors using Bayesian techniques when new load tests are added to the database. More importantly the dissertation formulated a design and acceptance protocol that seeks to unify the level of reliability for deep foundations through both the design and construction phases. As a verification mechanism to the developed design and acceptance protocol, a full-scale pile load testing program was recommended. The testing program would be composed of ten driven piles that had been dynamically and statically load tested. It was found that, for the same required reliability level, acceptance criteria could be lowered if more piles are tested on a jobsite. Subsequently, a non-contact instrument--such as Pile Driving Monitoring device-is recommended to verify in situ pile capacity of each and every pile on construction site. The results from in situ pile capacity verification could be employed to update the calibrated resistance factors and to refine future designs.
Book Synopsis Calibration of Resistance Factors Needed in the LRFD Design of Driven Piles by : Murad Yusuf Abu-Farsakh
Download or read book Calibration of Resistance Factors Needed in the LRFD Design of Driven Piles written by Murad Yusuf Abu-Farsakh and published by . This book was released on 2009 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Inclusion of Horizontal Soil Variability in LRFD Design of Deep Foundations by : Awilda M. Blanco
Download or read book Inclusion of Horizontal Soil Variability in LRFD Design of Deep Foundations written by Awilda M. Blanco and published by . This book was released on 2005 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: Approximately 40 years ago, researchers started to use probability theory to develop a more rational basis for civil engineering design. New methods like Load and Resistance Factor Design (LRFD) allowed for the use of factors to increase the load effect (load factors) and decrease the calculated resistance (resistance factors) for the structure to account for uncertainty in these parameters. The initial main approach for developing resistance factors for geotechnical design was to adjust the resistance factors to be consistent to the factors of safety used for design in the allowable stress design (ASD) methodology. The latest efforts involved the development of resistance factors based on driven pile and drilled shaft information from a national database, but further uncertainties remain due to individual site conditions, among others. Although the vertical soil variability has been modeled and included in design, the horizontal soil variability for the design of driven piles should not be determined using the same models. The main objective of this research is to characterize the soil variability in the horizontal direction at an alluvial site. The variability is included in the determination of LRFD resistance factors for the design of driven piles. Different methodologies are presented to attempt to describe the horizontal soil variability to provide guidance to designers on how to divide any site based on this variability. An example is presented on how these methodologies can be applied to design structures either within a distance where information is available or outside the distance where information is available.
Book Synopsis Calibration of Resistance Factors for Axial Capacity of Driven Pile Into Missouri Soil by : Mulugeta Abay Kebede
Download or read book Calibration of Resistance Factors for Axial Capacity of Driven Pile Into Missouri Soil written by Mulugeta Abay Kebede and published by . This book was released on 2010 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Over the past two decades the load resistance factor design (LRFD) has been accepted by the American Association for Transportation and Highway Officials (AASHTO) for the design of bridges. This approach is now gaining widespread popularity in the United States for substructure bridge design, including the design of driven pile foundations, as the states calibrate the geotechnical resistance factors for local geological conditions and practices. This study presents the geotechnical resistance factors calibrated for axially driven pile using the first-order reliability method (FORM) for the target reliability index of 2.33 and 3.0 based on 64 end-of-drives (EOD) and 22 beginning-of restrike (BOR) pile driving analyzer (PDA) test data from nine bridge sites in Missouri. Three static pile capacity prediction methods were used, i.e. the Nordlund, Meyerhof and Beta methods. The work investigated the efficiency of each method based on the bias factor, the ratio of the measured to the predicted capacity of the pile, ([lambda] = R[subscript m]/R[subscript p]), the coefficient of variation (COV), and efficiency factor or the ratio of the resistance factor to the bias factor, ([phi]/[lambda]). It verified that the Beta and Nordlund methods provide better predictions than the Meyerhof method. In addition, a comparison of the resistance factor in current AASHTO LRFD with the calibrated resistance factor shows that validating the resistance factors in the AASHTO may result in less reliable design. Finally, the recommended resistance factors for LRFD design are provided for use in Missouri. In addition, further refinement of the developed resistance factors is recommended to improve the resistance factors using large quantity and high quality of data that cover wide areas the glaciated plain and southeast lowland geological regions"--Abstract, leaf iii.
Book Synopsis Load and Resistance Factor Design (LRFD) Pile Driving Project - Phase II Study by : Aaron S. Budge
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 Synopsis Load and Resistance Factor Design and Construction Control of Driven Piles in Intermediate Geomaterials by : Pramila Adhikari
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 Synopsis Driven Pile Load Test Data Analysis and Calibration of LRFD Resistance Factor for Mississippi Soils by : Eric Steward
Download or read book Driven Pile Load Test Data Analysis and Calibration of LRFD Resistance Factor for Mississippi Soils written by Eric Steward and published by . This book was released on 2018 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Load and Resistance Factor Design (LRFD) for Analysis/design of Piles Axial Capacity by :
Download or read book Load and Resistance Factor Design (LRFD) for Analysis/design of Piles Axial Capacity written by and published by . This book was released on 2002 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Key Aspects of LRFD Implementation for Driven Pile Capacity by Dynamic Methods by :
Download or read book Key Aspects of LRFD Implementation for Driven Pile Capacity by Dynamic Methods written by and published by . This book was released on 2015 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inputs and interpretation procedures for pile wave equation analysis, which correlates measured field dynamic driving response to axial pile static capacity, are highly dependent on site-specific soil conditions and field practices. The 6th Edition of the AASHTO LRFD Bridge Design Specifications provide generalized guidelines for pile design, but do not account for variability in region-specific soils and field practices. A comprehensive literature review of region-specific resistance factor recalibration efforts across the U.S. has given insight into the range of implementation issues encountered, especially the key decisions around choosing a restrike (BOR), along with measures of efficiency and treatment of time-dependent capacity gain through pile set-up for BOR. A reevaluation and statistical exploration of cases within the extensive Portland State University (PSU) Pile Load Test Database offers special insight into the implementation issues for the PSU recalibration effort specific to Oregon Department of Transportation (ODOT) and Pacific Northwest Practice. The information gathered from this research provides a general commentary on increased foundation reliability and guidance for approaches to implementation of LRFD bridge pile foundation design into practice.
Book Synopsis Load and Resistance Factor Design (LRFD) for Driven Piles Using Dynamic Methods--A Florida Perspective by : MC. McVay
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 Synopsis Development and Implementation of the DIGGS Format to Perform LRFD Resistance Factor Calibration of Driven Concrete Piles in Florida by : Mark Anthony Styler
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.
Book Synopsis Development of LRFD Procedures for Bridge Piles in Iowa by :
Download or read book Development of LRFD Procedures for Bridge Piles in Iowa written by and published by . This book was released on 2012 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the goal of producing engineered foundation designs with consistent levels of reliability as well as fulfilling the Federal Highway Administration (FHWA) mandate that all new bridges initiated after October 1, 2007 be designed according to the Load and Resistance Factor Design (LRFD) approach, the Iowa Highway Research Board (IHRB) sponsored three research projects on driven piles (TR-573, -583 and -584). The research outcomes are presented in three reports entitled Development of LRFD Design Procedures for Bridge Piles in Iowa, Volumes I, II, and III, and other research information is available on the project web site at http://srg.cce.iastate.edu/lrfd/. Upon incorporating the regional LRFD recommendations from the completed research into the Iowa DOT Bridge Design Manual (2010) as it is being rewritten under the new title of LRFD Bridge Design Manual (December 2011), and adopting the American Association of State Highway and Transportation Officials (AASHTO) LRFD Bridge Design Specifications (2010), this Volume IV for driven piles in Iowa was developed. Following the layout of a design guide, the application of the LRFD approach is demonstrated using various pile design examples in three different tracks, which depend on the construction control method used for establishing the pile driving criteria. Piles are designed using the Iowa Blue Book method. The pile driving criteria are established using the Wave Equation Analysis Program (WEAP) and the Pile Driving Analyzer (PDA) with a subsequent pile signal matching analysis using the CAse Pile Wave Analysis Program (CAPWAP) in Track 3. The track examples cover various pile types, three different soil profiles (cohesive, non-cohesive, and mixed) and special design considerations (piles on rock, scouring, downdrag, and uplift).
Book Synopsis Dynamic Pile Testing Technology by : Robert Y. Liang
Download or read book Dynamic Pile Testing Technology written by Robert Y. Liang and published by . This book was released on 2007 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: Driven piles are widely used as foundations to support buildings, bridges, and other structures. In 2007, AASHTO has adopted LRFD method for foundation design. The probability based LRFD approach affords the mathematical framework from which significant improvements on the design and quality control of driven piles can be achieved. In this research, reliability-based quality control criteria for driven piles are developed based on the framework of acceptance-sampling analysis for both static and dynamic test methods with the lognormal distribution characteristics. As a result, an optimum approach is suggested for the number of load tests and the required measured capacities for quality control of driven piles. Furthermore, this research has compiled a large database of pile set-up, from which the reliability-based approach of FORM is employed to develop separate resistance factors for the measured reference (initial) capacity and predicted set-up capacity. This report also provides a Bayesian theory based approach to allow for combining the information from the static pile capacity calculation and dynamic pile testing data to improve pile design process. Specifically, the results from dynamic pile tests can be utilized to reduce the uncertainties associated with static analysis methods of pile capacity by updating the corresponding resistance factors. This research has also developed one-dimensional wave equation based algorithm to interpret the High Strain Testing (HST) data for the estimation of the shaft and toe resistance of driven piles. The closed form solution is obtained for determining the Smith damping factor and the static soil resistance. Finally, a set of new wireless dynamic testing equipment (both hardware and software) is developed for more efficient dynamic pile testing.
Book Synopsis Load Resistance Factor Design (LRFD) for Driven Piles Based on Dynamic Methods with Assessment of Skin and Tip Resistance from PDA Signals by : Ariel Perez Perez
Download or read book Load Resistance Factor Design (LRFD) for Driven Piles Based on Dynamic Methods with Assessment of Skin and Tip Resistance from PDA Signals written by Ariel Perez Perez and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Eight dynamic methods to estimate the static capacity of driven piles were evaluated based on a Florida database and Load Resistance Factor Design (LRFD). The dynamic methods investigated were four stress wave approaches (CAPWAP, PDA, Paikowsky Energy, and Sakai Energy) and four driving formulas (ENR, modified ENR, FDOT, and Gates). In the case of the older driving formulas, the database was broken into both small (i.e. Davisson capacity less than 1779 kN) and large (Davisson capacity larger than 1779 kN) capacity piles. It was demonstrated that the modern methods based on wave mechanics, such as CAPWAP, PDA, and Paikowsky's energy method, are more accurate than the old driving formulas. The utilizable measured Davisson capacity, defined as [phi]/[lambda][subscript]R (ratio of resistance / mean capacity), shows that the new dynamic methods are more cost effective to meet a reliability index in comparison with the old methods based on momentum conservation. In addition, the Gates formula, when used separately for Davisson capacity larger than 1779 kN or less than 1779 kN, may have comparable accuracy with the modern methods. A suggested empirical method is presented to calculate the total, skin, and tip static resistance of driven piles. This method has proved to be equally or more accurate than the most widely used method (i.e. PDA, and CAPWAP). Additional features of the suggested method include determining the total, skin, and tip static capacities as the piles are being driven, saving construction time, therefore, saving construction costs.
Book Synopsis Load and Resistance Factor Design (LRFD) for Dynamic Analyses of Driven Piles by : Kirk L. Stenersen
Download or read book Load and Resistance Factor Design (LRFD) for Dynamic Analyses of Driven Piles written by Kirk L. Stenersen and published by . This book was released on 2001 with total page 832 pages. Available in PDF, EPUB and Kindle. Book excerpt:
