Development of Live Load model based on Weigh-In-Motion Data for Piers and Wharves at Port Terminals

Abstract: Load factors and load combinations in current pier and wharf design codes (e.g., UFC 4-152-01: piers and wharves) need to be calibrated using actual field data to ensure rationality and economic design of piers & wharves at port terminals. The field data includes, but is not limited to unbiased truck weights, axle configurations, and truck locations that can be measured using Weigh-In-Motion (WIM) technology. WIM sensors and loops are installed at various access points and locations within the Port Terminals. Data will be collected, remotely, based on daily, weekly and monthly intervals. Records of trucks and other types of heavy vehicles are processed to determine statistical distributions of gross vehicle weights, axle loads, and other parameters. A live load model for port terminal using “heavy” representative (i.e., upper tail) data will be developed. The recorded trucks are run through influence lines to calculate moments and shears and stability (sliding, overturning, etc.) for various limit states or potential failure modes. The obtained load spectra are compared with the results of truck surveys and permit records in the vicinity of port areas. Based on the established statistical characteristics of various parameters, Monte Carlo simulations will be employed to process various load combination scenarios including multi-hazard events (e.g., frequency and intensity of heavy vehicle passing). Comparison of different load combinations addressing live load plus multi-hazards will be performed using Reliability-based procedure to help validate the developed live load factors. The presented study provides the field data collection techniques, heavy vehicle database, and reliability-based procedure for the development of live load model and calibrated load factors for pier design and evaluation.

How does this project / topic contribute to the advancement of the industry and profession?: We believe that ports worldwide will benefit from this pilot project to collect unbiased live weight data as well as other type information of heavy vehicles to help understand the variation of live load and its impact on the design and service life of piers and wharves in ports.

Does the project / topic implement new and innovative techniques, materials, technologies, and delivery methods?: Yes, our Weigh-In-Motion (WIM) technology and sensors will help establish a new database of live load spectra that can be the basis for the calibration of live load factors applied in combination of various critical multi-hazard loading. The unbiased statistical distribution of such data will be critical for inclusion in a reliability-based procure for future code calibration adopted for design and evaluation of service life prediction of new and existing piers and wharves, respectively.

What was the most challenging aspect of your project / topic and how did you handle it to ensure success?: The most challenging would be to find the actual variation of live load data that would represent various geographical port areas with differing levels of operations and type of economic freight activities. There will be a need to perform similar studies on Ports that would be considered highly active and located in various parts of the USA.

Who is the target audience for this paper?: Seaport engineers, coastal engineers and scientists, marine terminal operators, and policy- and decision-makers will benefit from an understanding of our project goals and lessons learned. The presenter is very experienced structural engineer who collected national truck weight spectra for bridges. This work is being done in collaboration with coastal engineers to combine multi-hazard loading combination and develop a reliability-based design and evaluation criteria. This approach will help provide a multi-disciplinary approach for the development of a rational design specifications for future ports.