Why Should Contractors Focus on Pavement Smoothness?

By Todd Mansell

“Californians pay the highest prices to drive on the worst roads in the nation…” according to a 2002 annual survey of pavement condition data. A smooth riding road is the number one factor that “most significantly increases public satisfaction with the highway system1.” One might ask “What is the incentive to build smooth roads?” Although an incentive/disincentive smoothness specification is under development in California, this is not the primary reason that contractors should be interested in building a smooth road. This article focuses on the benefits to paving contractors who commit to constructing smooth pavements, regardless of incentives or disincentives provided by a smoothness specification.

One reason for placing smooth roads is that there is a trend toward more and more highway projects being funded at the local agency level. An example of paving projects made possible by funding outside of Caltrans or the Federal government comes from the Santa Clara Valley Transportation Authority (SCVTA). Projects totaling hundreds of millions of dollars that have been funded through bond measures and administered by the SCVTA are dependent on voter approval. In the same way that consumers will not knowingly purchase an automobile that is a “lemon,” why should they continue voting to allow their tax dollars to fund road construction that doesn’t satisfy their number one priority of smoothness?

Source: Federal Highway Administration, Office of Highway Policy Information. Total highway funding by all units of government reached $128.5 billion 2000, a 222.5% increase compared to 1980. At 63.0%, highway-user fees make up the largest share of revenues used to fund highways. When compared to the 56.9% in 1980, the present share has slightly increased. The General Fund share of highway funding has decreased from 21.0% in 1980 to 13.3% in 2000. Other taxes, investment income and bond proceeds account for 23.7% of the total highway funding as compared to 22.2% in 1980.

Another reason for paving smooth roads comes in anticipation of a trend toward more warranty work. Contractors who demonstrate an ability to place smooth pavements will have lower pavement maintenance and repair costs, providing a competitive advantage on bidding warranty jobs. Studies have shown that smoother roads reduce the impact (dynamic) loading forces exerted on a pavement when a tire “jumps” off the road and impacts it again at high speed. The Kansas Department of Transportation (KDOT) estimates maintenance cost savings of from reduced dynamic loadings of $10,000 per mile for the first year and an increase in maintenance savings for the life of the pavement. This is supported by studies that show much lower highway maintenance costs when pavements are placed to initial minimum smoothness requirements. Some experts estimate that increasing pavement smoothness by 25 percent results in a 10 percent increase in the life of the pavement. This is good information for contractors working under warranty contracts. In states such as Ohio and Wisconsin where warranty contracts are common, the most recent trend has been toward extended warranty periods of up to seven and ten years. To be successful on seven and ten-year warranties requires exceptional project management, materials and workmanship by contractors who wish to remain competitive.

How much does it cost to place a smoother pavement? Very little initially, and eventually nothing! Achieving smooth roads requires no new equipment for most contractors. Smooth pavements are a result of developing and following a detailed paving plan and having a well-trained and motivated paving crew. If smooth roads are the goal, it’s up to management to thoroughly understand the benefits and cost savings of placing a smooth pavement and to effectively communicate that goal to the paving crew. Many managers have “money myopia,” which is a shortsighted view of profit and loss. When the slight additional costs of placing a smooth pavement today are calculated to include the benefits of having a smooth pavement tomorrow, the choice is obvious — a smooth pavement today will save money in the long run. This is how the Japanese automakers have done so well against their North American rivals. For example, Toyota had a long-term vision to produce quality vehicles that last longer and have lower, long-term maintenance costs. The pay-off to Toyota in increased sales is obvious to anyone who reads today’s newspapers and business journals. In the next few years, Toyota is projected to sell more vehicles worldwide than General Motors who has been the world leader for decades2. Why? Because Toyota recognized their customers’ number one priority was reliability and they committed to a long-term vision of producing the quality vehicles that people demanded. Did it cost Toyota more in the short-term? Yes. Has it paid off? Yes. Will it continue to pay off? It appears that way based on their growing market share. So how does Toyota’s vision relate to roadway smoothness? Toyota is focused on producing vehicles that have fewer breakdowns and lower repair costs over the life of the vehicle. Reliability satisfies automobile customers’ number one priority3 while costing Toyota less for warranty and repair work. In the same way, smooth roads satisfy the motoring public’s number one priority, which will only strengthen public support for tax dollars to build smooth roads.

What is a second major reason why contractors should make a commitment to build smooth roads? Smoothness goals motivate the paving crew to produce the best work possible. As mentioned earlier, the public’s number one priority with road construction is a smooth riding surface. This is how paving crews are judged by their friends, family, and competitors. Paving crews are often judged on the ride quality of the final product, but are given conflicting mandates for completing the work. For example, the paving crew may be limited to no leveling or told to reduce the quantity of asphalt or concrete used, but they are held responsible for the final ride. This is not only unfair, but also completely unreasonable. Managing this way is the quickest way to guarantee that you will only get the minimum amount of effort from your workers. Where is the motivation to work hard and to do the best job possible only to be criticized when you can do less work and be criticized to the same level? What’s the incentive to do a better job? There isn’t one when conflicting mandates exist. Setting smoothness as a top priority will motivate your paving crew to be innovative, creative, and efficient. As a manager you will receive a better product because the crew is giving 110% effort to achieve the smooth ride that their reputation is based on. It is often said that contracts are structured to prohibit achieving smoothness and making a profit at the same time. Although there is room for improvement in alignment between the specification writing and the expectation for smoothness by the owner, contract language does not prevent a contractor from making an effort to focus on smoothness. Improvements in pavement smoothness can be made under any conditions — certain conditions will simply be more favorable than others. As long as the road is being paved, there’s an opportunity to improve the ride quality.

Finally, the biggest objection heard from project managers is that a focusing on smoothness costs money with no reward. This is simply not true. The single most important requirement for paving smooth roads is a continuous, balanced paving operation. Managing a continuous operation that delivers mix to the paver in an evenly-spaced manner consistent with the production rate of the HMA or PCC plant will not only produce the smoothest possible pavement, but also reduce costs by optimizing the number of trucks required to deliver mix to the paver. A reduction of one or two trucks will result in substantial cost savings over the course of a project. The end result of a focused effort on managing trucking is a smoother pavement at an equivalent or lower cost. There are several options available to manage trucks. One option includes the use of a “truck boss” who is situated at the plant to assist trucks with maintaining a predetermined spacing. For example, the paving plan may determine that a balanced operation is achieved when trucks are loaded and leave the plant site every four minutes. If truck management is a serious problem, another solution is to have a truck boss at the plant and one truck boss on site. Each truck boss should have radio communication and a clipboard with all the trucks listed on it. The cycle time is known from measurements taken on the previous shift or measured by someone driving the route under the typical traffic conditions that occur during the paving window. The truck boss at the plant notifies the field truck boss when a truck leaves the plant. The on-site truck boss notes the departure time and notes when the truck arrives on site. The actual time is compared with the expected cycle time. Unusually long cycle times are addressed by talking with the driver to discover the reason and, if necessary, educate him on the importance and the expectation that mix should be delivered in a consistent manner from load-to-load. Other options for managing trucks include using global positioning system (GPS) technology to track truck location and cycle times. This information can be used in a similar manner as truck bosses to manage truck flow. Simple calculations will determine that the preceding options will more than recover the additional costs of truck bosses or GPS units over the course of most projects where consistent truck spacing is a challenge. In most cases, over time, truckers will change their behavior once they realize and understand what is expected of them. Many times, no one has explained why it is important to maintain spacing nor have the truckers been provided a paving plan to know what is expected of them. Trucking plays a critical role in achieving a smooth pavement and they should be included in the planning process. Incentives could be considered for drivers who maintain consistent spacing according to the paving plan.

From a quality control perspective, regardless of whether or not a smoothness specification is included in a contract, smoothness measurement provides a “one-stop” measurement that drives improvements in mat texture, minimizes thermal and rock segregation, and improves compaction through more consistent mix temperatures, paver speed, and consistent rolling operations. When roller operators are forced to stop because the paver is stopped, the rolling pattern gets interrupted, and the result is a bump in the mat from the paver and bumps created by the rollers stopping on the mat.

In summary, when you plan your next paving project, consider focusing on smoothness with the expectation that the end result will be a smoother riding surface that will increase public support for future road construction dollars. A focus on smoothness will motivate your paving crew to give you their best effort because they take pride in the ride quality of the finished roadway. Also consider the cost savings that you will realize by focusing on what it takes to achieve a continuous trucking and paver operation. Diligent truck management will reduce the number of trucks needed and reduce the time that the paving crew is getting paid waiting for trucks. Paving for smoothness creates a win-win situation for the owner who must answer the public demand for smooth roads and the contractor who benefits from reduced costs, a good reputation for quality with owners, and a motivated paving crew who will enjoy doing the best work that they can do. Will a pavement smoothness specification help? Sure it will. Does it make good business sense to pave smooth roads without a smoothness specification in place? You bet!

  1. Report by The Road Information Program (TRIP), (a national, non-profit research organization) based on year 2002 data supplied by the Federal Highway Administration.
  2. “Toyota Plan Could Leave No. 1 GM in the Dust”, Associated Press, September 21, 2006.
  3. A recent Consumer Reports survey observed that fuel economy has surpassed reliability as the number one priority for new car buyers. 27% of survey respondents considered fuel economy their top priority as the Consumer Reports survey was reported by CNN August 23, 2006. Reliability was ranked second at 25%.