Infrastructure

Use of Recycled Asphalt Pavement in Rubberized Hot Mix Asphalt—Gap-Graded

Angel Mateos
Harvey, John
Wu, Rongzong
Buscheck, Jeff
Butt, Ali
Guada, Irwin
Bowman, Michael
Rahman, Mohammad
Brotschi, Julian
Yu, Justin
2024

Current Caltrans Standard Specifications for rubberized hot mix asphalt–gap-graded (RHMA-G) do not allow the inclusion of reclaimed asphalt pavement (RAP). This report summarizes the research conducted by the UCPRC in support of the Caltrans-industry initiative “10% RAP in RHMA-G,” whose goal is to evaluate the use of up to 10% RAP (by aggregate replacement) in RHMA-G mixes, provided that the research does not identify significant potential problems for durability. Five pilot projects were built by Caltrans as part the initiative. In each of the pilots, a control RHMA-G (without RAP) and...

Year-Twenty Performance Review of the First 40 Year Design Life Jointed Plain Concrete Pavements in California

Angel Mateos
Haider, Md Mostafa
Nassiri, Somayeh
Feldman, Dulce Rufino
Harvey, John
Lea, Jeremy
Butt, Ali Azhar
2025

This paper evaluates the half-life performance of the first three 40 year design life jointed plain concrete pavements built in California, in the early 2000s. The projects, two on I-15 and one on I-40, have a combined total length of 420 lane kilometers (260 lane miles), are in desert areas, and have heavy truck traffic. The pavement performance evaluation used data from the California Department of Transportation (Caltrans) pavement-management system (PMS) databases, including pavement condition surveys, field data, and construction histories. An in situ evaluation of the projects done...

Freeway Expansion and Land Development: An Empirical Analysis of Transportation Corridors

Mark Hansen
Gillen, David
Puvathingal, Mohnish
2001

Road transport infrastructure can, together with other factors, influence location choices and decisions involving residential, commercial, and industrial development. The network of roads and highways provides a means for access for workers and materials as well as a way for distributing products and services. Greater access lowers the costs of transportation and therefore increases the supply of many resources, including land, labor, and materials. An investment in highway infrastructure can have a variety of land use impacts, depending upon which of the above factors have been affected...

Influence of Capacity Constraints on Airline Fleet Mix

Mark Hansen
Gosling, Geoffrey D.
Margulici, Jean-David
Wei, Wen-Bin
2001

This report documents the findings of research sponsored by the Los Angeles World Airports to examine the influence of airport capacity constraints on airline fleet mix and to explore the potential effects of policy options to influence airlines to use larger aircraft types and thereby accommodate growth in passenger or cargo demand without a corresponding increase in the number of aircraft operations. This issue is of growing importance at many major airports in the United States and indeed around the world, as a steadily increasing demand for air transportation has resulted in volumes of...

Assessing URET Benefits for Airspace Users: A Quasi-Experimental Approach

Bolic, Tatjana
Mark Hansen
2002

Air traffic control organizations around the world are trying to develop automation tools to help controllers manage increasing workload and to enable user preferred routes. This paper focuses on such a tool: User Request Evaluation Tool (URET), which is a decision-support tool for en-route controllers. URET is a prototype of an automated conflict probe. Based on flight plans and actual radar tracks, the URET system models aircraft trajectories and predicts possible conflicts. It also enables controllers to check clearances for conflicts prior to their issuance. This tool is intended as a...

Influence of Capacity Constraints on Airline Fleet Mix

Mark Hansen
Gosling, Geoffrey D.
Margulici, Jean-David
Wei, Wen-Bin
2001

This report documents the findings of research sponsored by the Los Angeles World Airports to examine the influence of airport capacity constraints on airline fleet mix and to explore the potential effects of policy options to influence airlines to use larger aircraft types and thereby accommodate growth in passenger or cargo demand without a corresponding increase in the number of aircraft operations. This issue is of growing importance at many major airports in the United States and indeed around the world, as a steadily increasing demand for air transportation has resulted in volumes of...

Airport Road Access at Planet Scale using Population Grid and Openstreetmap

Sun, Xiaoqian
Wandelt, Sebastian
Mark Hansen
2020

A new comparative framework for estimating the road access of airports around the world at high resolution is proposed. While existing studies are spatially constrained and often require hand-collection of data, this framework relies on freely available datasets at planet scale: Population density database Gridded Population of the World and transportation infrastructure database Openstreetmap. Access profiles from the airport-centric view (how many passengers are close to a fixed airport) and the population-centric view (how many airports are close to certain grid cells) are presented as...

USE-LFA: A Data-Driven Framework for UAM Site Evaluation using Latent Factor Analysis

Sohn, Sungmin
Kim, Namwoo
Mark Hansen
Yoon, Yoonjin
2025

Urban air mobility (UAM) introduces new challenges for infrastructure planning, requiring data driven approaches for sustainable site selection. This study proposes USE-LFA (Urban Site Evaluation using Latent Factor Analysis), a framework designed to support equitable and environmentally conscious siting of urban ports. Applying latent factor analysis to 25 urban attributes in Seoul, the framework identifies six latent factors, grouped into two dimensions: Suitability and Attractiveness. These dimensions are combined through a tunable prioritization metric, enabling alignment with local...

Pilot Models for Estimating Bicycle Intersection Volumes

Julia Griswold
Medury, Aditya
Schneider, Robert J.
2011

Bicycle volume data are useful to practitioners and researchers to understand safety, travel behavior, and development impacts. This paper describes the methodology used to develop several simple models of bicycle intersection volumes in Alameda County, California. The models are based on two-hour bicycle counts performed at a sample of 81 intersections in the Spring of 2008 and 2009. Study sites represented areas with a wide range of population density, employment density, proximity to commercial property, neighborhood income, and street network characteristics. The explanatory variables...

National Pedestrian and Bicycle Safety Data Clearinghouse Phase I: Inventory & Framework

Nordback, Krista
Kumfer, Wesley
LaJeunesse, Seth
Thomas, Libby
Heuser, Katie
Julia Griswold
University of North Carolina at Chapel Hill. Highway Safety Research Center
University of California, Berkeley
2019

Safety researchers, especially those studying bicycle and pedestrian safety, often struggle to obtain sufficiently high-quality data to conduct robust safety studies. The goal of the project is to create an online centralized data clearinghouse for bicycle and pedestrian safety-related data as a national resource for safety researchers to expedite research on this topic. CSCRS Project R14, the first phase of this work, produced a pilot online pedestrian and bicycle safety data resource clearinghouse available at pedbikedata.org. It allows researchers to search from over 4,000 pedestrian...