Calibration of Load and Resistance Factor Design: Resistance Factors for Drilled Shaft Design

2002 ◽  
Vol 1808 (1) ◽  
pp. 108-111 ◽  
Author(s):  
Ching L. Kuo ◽  
Michael C. McVay ◽  
Bjorn Birgisson
Keyword(s):  
Resistance Factor ◽  
Drilled Shaft ◽  
Resistance Factors ◽  
Factor Design ◽  
Design Resistance ◽  
Load And Resistance Factor

scholarly journals Load and resistance factor design of drilled shafts subjected to lateral loading at service limit state

2018 ◽  
Author(s):  
◽  
Minh Dinh Uong
Keyword(s):  
Limit State ◽  
Design Procedure ◽  
Drilled Shafts ◽  
Resistance Factor ◽  
Lateral Loading ◽  
Drilled Shaft ◽  
Resistance Factors ◽  
Service Limit State ◽  
Load And Resistance Factor ◽  
Aashto Lrfd

Since 2007, the American Association of State Highway Administration Officials (AASHTO) has made utilization of Load and Resistance Factor Design (LRFD) mandatory on all federally-funded new bridge projects (AASHTO, 2007). However, currently, there are no guidelines implementing LRFD techniques for design of drilled shaft subjected to lateral loads using reliability-based analysis. On a national level, the AASHTO LRFD Bridge Design Specifications (AASHTO, 2012) specify that a resistance factor of 1.0 be used for design of drilled shafts subjected to lateral loading at service limit state, which means reliability-based analyses for calibration of resistance factors have not been performed. Therefore, there is a need to create a LRFD procedure for drilled shafts subjected to lateral loading at service limit state that has reliability-based calibrated resistance factors applicable for future projects. The research focuses on the reliability-based analysis of drilled shaft subjected to lateral loading, characterize lateral load transfer model of drilled shafts in shale, probabilistic calibrate resistance factor and contribute to the development of design procedure using LRFD. The objective of this work is to improve the design of drilled shaft subjected to lateral loading using LRFD at service limit state by providing a more reliable design procedure than the current AASHTO LRFD procedure for drilled shafts subjected to lateral loading at service limit state.

Calibration concepts for load and resistance factor design (LRFD) of reinforced soil walls

2008 ◽  
Vol 45 (10) ◽  
pp. 1377-1392 ◽  
Author(s):  
Richard J. Bathurst ◽  
Tony M. Allen ◽  
Andrzej S. Nowak
Keyword(s):  
Limit State ◽  
Reinforced Soil ◽  
Resistance Factor ◽  
Resistance Factors ◽  
Soil Walls ◽  
Calibration Methods ◽  
Load And Resistance Factors ◽  
Factor Design ◽  
Load And Resistance Factor ◽  
Reinforced Soil Walls

Reliability-based design concepts and their application to load and resistance factor design (LRFD or limit states design (LSD) in Canada) are well known, and their adoption in geotechnical engineering design is now recommended for many soil–structure interaction problems. Two important challenges for acceptance of LRFD for the design of reinforced soil walls are (i) a proper understanding of the calibration methods used to arrive at load and resistance factors, and (ii) the proper interpretation of the data required to carry out this process. This paper presents LRFD calibration principles and traces the steps required to arrive at load and resistance factors using closed-form solutions for one typical limit state, namely pullout of steel reinforcement elements in the anchorage zone of a reinforced soil wall. A unique feature of this paper is that measured load and resistance values from a database of case histories are used to develop the statistical parameters in the examples. The paper also addresses issues related to the influence of outliers in the datasets and possible dependencies between variables that can have an important influence on the results of calibration.

The basis for load and resistance factor design criteria of steel building structures

1977 ◽  
Vol 4 (2) ◽  
pp. 178-189 ◽  
Author(s):  
T. V. Galambos ◽  
M. K. Ravindra
Keyword(s):  
Research Work ◽  
Resistance Factor ◽  
Building Structures ◽  
Resistance Factors ◽  
First Order ◽  
Steel Building ◽  
Load And Resistance Factors ◽  
Factor Design ◽  
Load And Resistance Factor ◽  
Work Done

This paper will detail the assumptions, the first-order probabilistic basis, the calibration, and the proposed format of load and resistance factor design (LFRD) criteria for steel building structures. Specifically, the paper will concern itself with the background and the choice of the particular first-order model, with the data bases used in evaluating the loading and the resistance functions, with the calibration procedures, and with the final selection of the load and resistance factors. The method will be illustrated by the examples of beams and columns under dead and live loading. The paper will conclude with a brief review of the research work done in connection with the development of LRFD criteria for steel building structures.

Load and Resistance Factor Design for Nuclear Pipes: Benefits and Challenges

2008 ◽  
Author(s):  
Kleio Avrithi
Keyword(s):  
Resistance Factor ◽  
Engineering Practice ◽  
Feed Water ◽  
Piping System ◽  
Reliability Indices ◽  
Resistance Factors ◽  
Load Factors ◽  
Factor Design ◽  
Load And Resistance Factor ◽  
Selection Of

The Board on Nuclear Codes and Standards (BNCS) recently decided to promote standards that use risk-informed design methods. In civil engineering practice a risk informed method, namely the Load and Resistance Factor Design (LRFD), has been in usage for quite some time. It is possible to extend such methods to the design of safety-related piping as well. This paper provides a brief overview of the LRFD method. Discussion is included for load factors to be used to account for the uncertainties in piping loads (e.g., internal pressure, sustained weight, etc.) and resistance factors to be used for addressing the uncertainties in strength of piping and analysis methods. Different load factors and resistance factors can be suggested for each load type and resistance type (e.g., hoop stress, bending stress, etc.). A design example for a feed water Class 2 piping system is provided to demonstrate the benefits of LRFD. This way, benefits such as the achievement of consistent reliability levels and the facilitation of a detailed risk analysis of mechanical systems are illustrated. Finally, the challenges associated with development of the LRFD method for nuclear piping are discussed. Such challenges pertain to the selection of the appropriate target reliability indices for piping, the development of equations for components such as tees, elbows, etc.

Load and Resistance Factor Design of Driven Piles

1996 ◽  
Vol 1546 (1) ◽  
pp. 88-93 ◽  
Author(s):  
George G. Goble
Keyword(s):  
Quality Control ◽  
Highway Bridges ◽  
The United States ◽  
Resistance Factor ◽  
Limit States ◽  
Resistance Factors ◽  
Nominal Strength ◽  
Factor Design ◽  
Load And Resistance Factor ◽  
Driven Pile

A load and resistance factor design (LRFD) bridge specification has been accepted by the AASHTO Bridge Committee. This design approach is now being implemented for highway bridges in the United States, including the design of driven pile foundations. To test the new specification's practicality and usefulness, an example problem has been solved using it. In the example, a pipe pile was designed to be driven into a granular soil to support a bridge column subjected to a factored axial compression load of 10 MN. The nominal strength selected for the pile was 1.58 MN with an estimated length of 25 m. Since the resistance factors are defined by the specified quality control procedures, the number of piles required in the foundation also depends on the quality control. In this example, the number of piles required varied from 15 to 8 with improved quality control, for a savings of almost half of the piles. This example indicated that the new AASHTO LRFD specification for driven pile design can be used effectively to produce a more rationally designed foundation. Some modifications should be made to include additional serviceability limit states, and additional research may indicate that changes should be made in some of the resistance factors.

Sign in / Sign up

Export Citation Format

Share Document