Asphalt Pavement Alliance Documents:

CLEANER WATER WITH ASPHALT PAVEMENTS

Asphalt pavements can be excellent tools in improving water quality, says a new white paper from the Asphalt Pavement Alliance. "The APA's newest publication scientifically documents the beneficial effects asphalt pavements can have on water quality," according to Dr. Howard Marks of the National Asphalt Pavement Association. Dr. Marks is the report's principal author and serves as co-chair of the team that produced the document. "The green benefits of 100 percent recyclable asphalt pavement might be surprising to some. For improved stormwater management, clean drinking water, and reduced roadside pollution, asphalt pavements are clean and environmentally beneficial," he continued.

The publication, "Cleaner Water With Asphalt Pavements," is available as a free download here.

THE ROLE OF ASPHALT IN LIVABLE COMMUNITIES

“Livable community” has become the new buzzword in urban planning and transportation circles. With the U.S. population expected to increase by 100 million over the next 40 years, effective coordination of policies related to housing, transportation, energy, and the environment will be necessary to ensure quality of life while expediting the flow of both freight and people in the safest and most cost-effective manner. There are, however, some differing ideas on what defines a “livable community”.

To download the complete article to read more about asphalt's role in a livable community, click here.

KEYS TO A SUCCESSFUL ALTERNATE BID PROCESS

Alternate bidding is a complex subject, but a new, user-friendly white paper, Keys to a Successful Alternate Bidding Process (order number IM-50), breaks it down for contractors and agencies. It outlines the procedures set up by the Federal Highway Administration and covers the factors considered in alternate bids, such as initial cost, construction time, and future costs. Also discussed are discount rates, performance periods, rehabilitation plans, salvage value, analysis periods, and more. The publication is available as a free download here.

The Best Value for the Taxpayer – A Public Trust

In making any decision concerning the type of pavement to use on a roadway, a road agency is obligated to get the best value for the taxpayers. Some promoters would argue that the agency should determine pavement type on the basis of whether a particular industry “needs the work.” The APA’s response is that the pavement type selection process should be used to select the best possible pavement type for a given road – in other words, it should be a road user-oriented process, not an industry-oriented process.

In order to deliver the best value for taxpayers and road users, the system used to select pavement type should be

Objective
Defensible
Understandable
Based on historical records
Primarily driven by economics
Periodically reviewed

Asphalt pavements possess many advantages in. Among these are:

Low initial cost
Low maintenance costs
Flexibility and speed of construction
The ability to handle heavy loads
Long life
Complete recyclability
Environmental, social, and economic sustainability

Furthermore, asphalt pavements allow an opportunity to reduce traffic noise at the source and improve ride quality. These are a few of the reasons that asphalt pavements should be considered in every pavement type decision.

For the APA's 2010 position paper on pavement type selection, click here.

Life-Cycle Cost Analysis

The APA has developed life-cycle cost analysis (LCCA) software that uses the principles recommended by the Federal Highway Administration (FHWA) to compare the economics of alternative designs for a given road project. It’s easy to use, unbiased, and free. There are two versions: LCCA Original, a comprehensive program, and LCCAExpress, geared to less-complex projects. Both are available as free downloads.
• Download LCCA Original 3.1
• Download LCCAExpress 1.0

Carbon Footprint - How does asphalt stack up?

Transportation officials are striving to make their practices and policies greener and more sustainable. So how do you measure the greenness of a pavement? It's all about the carbon - how, when and whether it is counted.

This paper examines greenhouse gas production of asphalt and concrete pavements. The analysis shows clearly that asphalt has a much lower carbon footprint than concrete. When it comes to pavement, asphalt is the more sustainble choice.

Download the full document here .

High Performance Intersections

Heavy trucks that are stopping, turning, accelerating or climbing expose pavements to high levels of stress. The technical publication High-Performance Intersections provides useful guidelines to the pavement designers who deal with the challenges of intersections and other high-stress pavements. The eight-page publication is available free by clicking here.

High-Performance Intersections lays out a four-point strategy to ensure good performance for intersections and other high-stress pavements. It chronicles two head-to-head intersection competitions between asphalt and concrete. Results from both competitions confirm that asphalt intersections take less time to construct, cost less to maintain, and provide a more durable, safer, and smoother surface on which to drive. The publication also discusses the "World’s Strongest Intersection."

Perpetual Pavement: A Synthesis

The concept of Perpetual Pavements was introduced in 2000 by the Asphalt Pavement Alliance (APA). They defined a Perpetual Pavement as "an asphalt pavement designed and built to last longer than 50 years without requiring major structural rehabilitation or reconstruction, and needing only periodic surface renewal in response to distresses confined to the top of the pavement" (APA, 2002).

At that time, it was recognized that many well-built, thick asphalt pavements that were categorized as either full-depth or deep-strength pavements had been in service for decades with only minor periodic surface rehabilitation to remove defects and improve ride quality.
Click here to go to downloadable document (.pdf)

ADDITIONAL RESOURCES – PAVEMENT TYPE SELECTION:

Expected Service Life & Performance Characteristics of HMA
Full report of the results of the study that documents the performance trends and characteristics of 372 test sections, each 500-ft. wide by one-lane wide, using distress data extracted from the LTPP database released in January 2002.

Tech Brief-Expected Service Life & Characteristics of HMA
Executive summary of the results of the study that documents the performance trends and characteristics of 372 test sections, each 500-ft. wide by one-lane wide, using distress data extracted from the LTPP database released in January 2002.

ADDITIONAL RESOURCES – LIFE CYCLE COST:

Evaluation of Expenditures on Rural Interstates in Kansas (Cross Study)
This study involved the evaluation of rural interstate pavements on I-35, I-135 and I-70 in Kansas that were administered by the Kansas DOT.

Ohio Interstates are Long-Lasting and Economical
Researchers in Ohio studied reconstruction data for interstate highways in the state. They found that the structure of the original asphalt pavements have remained in service, while concrete pavements of comparable age have been removed and replaced.

Pavement Life-Cycle Cost Studies Using Actual Cost Data, A Synthesis
This synthesis presents the results of studies of interstate highways in three states which show the comparison of costs between hot-mix asphalt (HMA) pavements and Portland cement concrete (PCC) pavements.

Tech Brief-Performance Trends of Rehabilitated AC Pavement
Publication No: FHWA-RD-00-165. This Tech Brief summarizes the results of a study of the General Pavement Study-6 (GPS-6) experiments, entitled "Performance of Rehabilitated Asphalt Concrete Pavements in the LTPP Experiments - Data Collected Through February 1997." The study documents performance trends of the 125 GPS-6 test sections using distress data collected.

Quantifying the Benefits of Polymer Modified Asphalt
From the Spring 2005 Edition of Asphalt magazine. How do I quantify the benefits of PMA from an agency perspective? The Asphalt Institute answers this question in this definitive study using national field performance data to determine enhanced service life of pavements containing polymer-modified binders.

Understanding the True Economics of Using Polymer-Modified Asphalt
This is a follow-up to the related article published in the Spring 2005 edition of Asphalt magazine that discussed a study titled "Quantifying the Effects of PMA for Reducing Pavement Distress". This study analyzed an extensive collection of field performance data, making direct comparisons between polymer-modified asphalt (PMA) mixes and unmodified conventional mixes.