Safety

Introduction

Safety on the road goes beyond responsible driving practices — Americans want their roads to be well-maintained to ensure a safe, smooth ride. When pavement is rough, uneven, or made hazardous by weather conditions, drivers and their families may be put at risk. In fact, in 2010 32,885 individuals died in the U.S. as a result of poor roadway conditions.1 The total cost of crashes, in terms of medical, workplace, legal, and administrative costs, emergency services, lost wages, and lost lives, in the country is nearly $3 billion.2

Substandard roads can cause a loss of vehicle control, driver fatigue, and an increase in frequency of lost-load accidents.3 As pavement serviceability decreases and roughness increases, traffic-related crashes are also likely to increase.4 For these reasons, keeping roads in a state of good repair and ensuring a smooth pavement with a high level of performance is important. Easy-to-maintain asphalt is the pavement of choice for safety. It provides drivers with a smooth, skid-resistant surface, excellent gripping power, and ultimately, a safer ride.

Key Pavement Technologies

Asphalt is the best pavement option for hazardous weather conditions. For example, one type of asphalt surface, known as open-graded friction course (OGFC), allows rainwater to drain through the surface layer and off to the sides while still providing good skid resistance.5 This reduces the amount of splash and spray produced by vehicles, improving visibility and safety.

Surfaces paved with open-graded asphalt have been shown to greatly reduce traffic accidents and related fatalities. For example, in the mid-2000s, the Texas Department of Transportation placed an open-graded asphalt surface on several roads with a high accident frequency. A year later, despite a large increase in rainfall, the roads experienced a significant decrease in crashes, injuries, and fatalities, likely due to the improved skid resistance, reduced splashing and improved visibility.6

Also, because asphalt pavements are generally darker in hue, they require less salt or other deicing treatments to ensure clear winter roadways compared to light colored pavements7^,19 In fact, at pavement temperatures below 15°F, the use of deicing salts on snow-covered roadways and bridges are not as effective and additional chemicals are often required,8 which can have a negative environmental impact.9 When deicers are needed, they generally do less damage to asphalt pavements than other road surfaces.10

The darker color can also provide greater contrast with white and yellow stripes, increasing the visibility of pavement markings.11 All types of pavement marking systems can work well on asphalt pavements,12 and there is evidence that markings remain effective longer on asphalt13 even in heavy snow areas.14 For thermoplastic markings, in particular, asphalt pavements provide a tighter, stronger bond than concrete pavements.15

Emerging Research

A National Cooperative Highway Research Program (NCHRP) study found that 13.5 percent of fatal crashes and 18.8 percent of all crashes occur when the pavement surface is wet.16 These findings have increased industry emphasis on ensuring the pavement surface are maintained to ensure a safe driving experience. In 2013, the Louisiana Transportation Research Center prepared a technical report for the Louisiana DOT highlighting the use of OGFC mixtures to enhance safety and performance. The report finds that the primary benefits of OGFC asphalt pavements are improved safety, driver comfort and environmental benefits resulting from smoother pavements, which increase fuel economy and reduce pavement noise.17 OGFC pavements reduced hydroplaning, pavement glare and splash/spray, which led to an increase in driver confidence.17

Drivability

Asphalt is the answer to building and maintaining smooth, good roads for safety. From technologies like open-graded asphalt pavements to natural attributes like strong gripping power and skid-resistance, asphalt provides drivers with an even, smooth surface that can keep them and their families safe. Using open-graded asphalt has been proven to reduce traffic accidents and related fatalities, and asphalt pavements typically require less deicing treatments than other pavements.

Because asphalt pavements are quick to construct and easy to maintain, they can be kept smoother and safer more cost-effectively over the years. Asphalt’s naturally smooth and skid-resistant surface18 helps to maintain quality roadway conditions and reduce the cost of maintaining your vehicle.

Sources