Asphalt pavement uses hot asphalt (bitumen) as its core material. The asphalt is heated to a plastic state, then mixed with aggregates and other components in specific proportions to form asphalt mix, which is finally laid to form the pavement. The application history of this material dates back thousands of years, with ancient civilizations using it for waterproofing purposes. In modern times, asphalt pavement has been widely adopted in various applications such as roads, airport runways, highways, and race tracks due to its excellent durability and adaptability.
The core characteristics of asphalt form the foundation of its advantages: it possesses high viscosity and excellent adhesion, enabling it to bond tightly with aggregates and other surfaces; its waterproof properties prevent moisture from penetrating the roadbed and causing damage; its elasticity and flexibility enable it to withstand stress caused by load and temperature changes; it resists deformation under load and high temperatures, has strong weather resistance, and can adapt to different climatic conditions; it also has high skid resistance, ensuring driving safety. These characteristics collectively contribute to the comprehensive advantages of asphalt pavements.
Core Advantages of Asphalt Pavements
Excellent Driving Experience
Asphalt pavements provide users with a superior driving experience. They feature a multi-layer structural design, with materials continuously laid using asphalt pavers, ensuring continuous material flow throughout the process. This fundamentally eliminates the bumpiness and noise caused by construction joints in traditional pavements. This continuous construction characteristic results in a smooth and flat asphalt pavement surface, minimizing vehicle vibration and significantly reducing interior noise. Compared to the rigid joints of concrete pavements, the “quiet effect” of asphalt pavements is particularly noticeable, even at high speeds, allowing occupants to experience a noticeable sense of quietness.
This smoothness not only enhances comfort but also brings about synergistic effects in energy savings and environmental protection. The smooth surface reduces rolling resistance during vehicle operation. Actual calculations show that this can reduce fuel consumption by up to 5%. For a heavy-duty truck traveling 100,000 kilometers annually, this alone can reduce carbon dioxide emissions by approximately 1.2 tons per year. For electric vehicles, lower rolling resistance can also indirectly increase actual range, aligning with current green mobility demands. In airport scenarios, asphalt-paved runways and taxiways reduce aircraft body vibrations during takeoff and landing due to their smoothness, thereby lowering the risk of body wear and tear while providing passengers with a smoother takeoff and landing experience.
Good economic performance
The economic advantages of asphalt pavements span the entire lifecycle. From an initial investment perspective, the production process for asphalt mixtures is relatively simple, with lower costs for raw material acquisition and processing. Initial paving costs are generally lower than those for concrete—especially in small-scale scenarios such as residential area roads and rural paths, where the cost advantage is more pronounced. Additionally, asphalt construction efficiency is extremely high, with paving times for the same section being 30%-50% faster than concrete, significantly reducing traffic control periods. For busy urban arterial roads, opening traffic one day earlier can reduce commuting delay costs by millions, yielding significant indirect economic benefits.
More importantly, the “economic efficiency” of asphalt pavements also manifests in long-term benefits. Asphalt is currently one of the most recyclable building materials, with recycled asphalt containing a high proportion of asphalt components (as asphalt is the most expensive component in asphalt mixtures). Recycled asphalt can be reused after simple heating treatment, saving over 40% of new asphalt procurement costs. Additionally, recycled asphalt can be transported to processing sites nearby (within a 50-kilometer radius), reducing transportation energy consumption and costs by 30%. Taking Europe as an example, its asphalt recycling rate has reached 87%, reducing aggregate mining demand by over 100 million tons annually, thereby conserving resources, lowering engineering costs, and forming an economic closed-loop characterized by “low short-term investment and stable long-term returns.”
High safety
Asphalt pavements prioritize safety throughout the entire chain from design to application. In terms of weather resilience, new asphalt technologies enable rapid dispersion and drainage of surface water. Porous asphalt materials achieve drainage rates of up to 30 liters per minute per square meter, capable of draining moderate rainfall within 10 minutes. This significantly reduces water mist during rainy conditions, lowers the risk of hydroplaning, and keeps road markings clearly visible, enhancing driving visibility. The smooth surface of the asphalt is not a “slip hazard” but rather increases the contact area between tires and the road surface. Combined with specifically designed textures, this significantly enhances anti-slip performance—on sections requiring emergency braking, optimizing the texture of the asphalt mixture can reduce braking distance by 15%-20%.
In terms of traffic guidance and warning, the application of colored asphalt has become an important safety aid. Red asphalt can be used as a “speed reduction warning strip” around schools, while yellow is used to mark bus lanes. These vividly colored road surfaces can quickly attract drivers’ attention, with visual recognition improved by 40% compared to ordinary road surfaces, reducing the risk of vehicles entering restricted areas. The contrast between black asphalt surfaces and white traffic markings is 25% higher than that of concrete surfaces. The markings have stronger adhesion and a lifespan extended by 100%, allowing drivers to clearly identify traffic rules even under nighttime lighting. Additionally, asphalt construction is fast, with a “quick setup, quick completion” model reducing the exposure time of construction personnel and road users in the construction area, thereby mitigating safety hazards from the construction phase.
Durable and easy to maintain
The durability of asphalt pavements has been proven through long-term practical application. They feature a layered structural design: the base layer has a larger thickness, primarily bearing the load from above, laid on an unbound granular layer; the intermediate layer (binder layer) has high strength, further distributing the load; the surface layer (30–40 mm) directly contacts vehicles. As long as the design is reasonable, construction is standardized, and maintenance is proper, the base layer and intermediate layer can maintain stable strength for decades without requiring complete reconstruction. For example, the surface layer made of asphalt mastic mixture can have a service life exceeding 30 years; when the surface layer wears out, it can be milled off and a new surface layer laid, and the milled-off old material can be reused in the production of new asphalt layers, achieving “recycling.” The latest self-healing asphalt technology, which utilizes the material’s inherent粘性 to automatically heal micro-cracks through temperature changes, holds promise for further extending pavement service life.
In terms of maintenance convenience, asphalt pavements have a clear advantage. Unlike concrete pavements, they do not have rigid joints, avoiding issues such as joint damage and frequent repairs; additionally, asphalt’s elasticity allows it to withstand freeze-thaw cycles without suffering severe damage like “cracking” due to temperature changes, significantly reducing maintenance requirements. After construction, there is no need for a lengthy curing period; the pavement can be opened to traffic once the temperature naturally drops below 50°C — typically within 2-3 hours in summer; if an emergency requires early opening, watering to cool the surface can further shorten the waiting time. When traffic volume increases, there is no need to remove the existing pavement; simply overlaying an additional layer of asphalt or widening the lanes can enhance load-bearing capacity. During upgrades, the road can remain partially open, minimizing disruption to traffic.
Strong sustainability
Asphalt pavement is widely recognized as a “green pavement,” with sustainability embedded throughout its entire lifecycle. In terms of material recycling, asphalt is one of the most easily recyclable construction materials. On average, 87% of recycled asphalt in Europe is reused in new asphalt mixture production, while 19% is used in subgrade construction, nearly achieving “zero waste.” During the recycling process, the asphalt components in old asphalt can be directly reused, reducing the need for new asphalt extraction—as asphalt is a byproduct of petroleum refining, recycling 1 ton of old asphalt is equivalent to saving approximately 0.8 tons of crude oil resources.
In terms of environmental protection and emissions reduction, technological innovations in asphalt pavement continue to advance. Warm-mix asphalt technology reduces the mixing temperature of asphalt mixtures by 50-80°C through the addition of special additives, thereby reducing fuel consumption during the heating process and lowering harmful gas emissions: Compared to traditional hot-mix asphalt, warm-mix asphalt reduces carbon dioxide emissions by 20%-40%, volatile organic compounds by 30%-50%, and nitrogen oxides by 60%-70%. Porous asphalt pavements enable natural rainwater infiltration. A 10,000-square-meter porous asphalt pavement can store 50 tons of rainwater, replenishing groundwater while replacing traditional stormwater drainage systems and reducing the risk of urban flooding. Additionally, asphalt has stable chemical properties and does not release harmful substances into soil or groundwater aquifers, making it commonly used as a waterproofing layer for drinking water reservoirs and an isolation layer for landfills, further highlighting its environmental friendliness.
High flexibility
The flexibility of asphalt pavement is evident throughout the entire process of design, construction, and application. In terms of design, it can be customized to meet specific needs: for suburban roads with low traffic volume, a thin layer of asphalt (5–8 centimeters) can be used; for highways that need to accommodate heavy trucks, the total thickness can exceed 15 centimeters; bridge surfaces, which must withstand vehicle loads and vibrations, can reduce bridge deck wear by adjusting the asphalt elasticity formula. In terms of climate adaptability, for cold regions with freeze-thaw cycles, asphalt’s elasticity can mitigate stress caused by temperature changes and prevent pavement cracking; for high-temperature regions, the mixture formula can be optimized to prevent rutting due to high temperatures.
In terms of construction and renovation, asphalt pavement offers greater flexibility. Urban areas are densely populated with infrastructure such as cables, water pipes, and sewage pipes. When excavation and maintenance are required, asphalt pavement allows for easy excavation, and after repairs are completed, it can be quickly backfilled and compacted, with traffic restored within 24 hours, minimizing disruption to urban traffic and residents’ daily lives. For adjustments to road functions, such as adding speed bumps, roundabouts, or widening/narrowing lanes, asphalt can be quickly implemented—compared to the cumbersome “demolition and reconstruction” process of concrete pavements, asphalt renovation efficiency improves by over 50%. This flexibility allows asphalt pavements to adapt to societal needs at any time, whether it’s adding bus-only lanes or renovating community pedestrian systems, all can be efficiently completed.
Excellent noise reduction effects
The noise reduction advantages of asphalt pavements significantly improve the traffic environment. Their smooth surface reduces vibration noise during vehicle operation, and their continuous construction without joints eliminates the “clunking” sounds caused by vehicles rolling over joints. Compared to concrete pavements, asphalt pavements can reduce driving noise by 3-5 decibels, with more noticeable reductions in interior noise at high speeds. The introduction of porous asphalt and quiet asphalt further enhances noise reduction capabilities: the porous structure of porous asphalt absorbs sound waves and reduces sound reflection, resulting in an additional 2-3 decibel reduction in noise compared to conventional asphalt surfaces.
This noise reduction not only enhances driving comfort but also yields practical benefits. Prolonged exposure to noise can lead to driver fatigue and increase the risk of accidents, while a quiet driving environment can alleviate driving stress. For residents living near roads, the low noise levels of asphalt surfaces reduce the disruption of traffic noise to daily life and decrease the need for noise-reduction facilities such as soundproof windows. In airport settings, the low noise characteristics of asphalt runways reduce noise propagation during aircraft takeoff and landing, making them more environmentally friendly for surrounding communities. It can be said that the noise-reduction advantages of asphalt pavements are an important manifestation of “people-oriented” transportation design.
Efficient and Convenient Construction
The construction process of asphalt pavements is efficient and easy to operate. In the material production phase, asphalt mixtures are produced in bulk at asphalt mixing plants, ensuring precise proportions and consistent quality; During transportation, insulation measures are used to maintain the temperature of the mixture. Once the materials are delivered to the site by dump trucks, they can be used immediately as long as the temperature meets standards and the mixture has not solidified into blocks, thereby avoiding material waste. During the paving process, asphalt pavers can achieve slow, uniform, and continuous paving, combined with roller compaction (at least two passes until no visible marks remain), enabling rapid completion of the pavement formation.
Most importantly, asphalt pavements do not require a lengthy “curing period.” Concrete pavements must be left to cure for 7–14 days after pouring to achieve sufficient strength before traffic can be permitted; however, asphalt pavements can be opened to traffic once the surface temperature naturally drops below 50°C. In summer, this condition is typically met within 2–3 hours, and in urgent situations, watering can further reduce the time required. This “lay and open” characteristic is particularly important for high-traffic sections—such as urban main roads under repair—as it maximizes the reduction of traffic congestion and minimizes economic losses caused by construction.
Wide adaptability
Asphalt pavement is adaptable to almost all traffic scenarios. At transportation hubs, airport runways and taxiways are paved with asphalt, whose smooth surface reduces turbulence during aircraft takeoff and landing, thereby lowering aircraft body wear; highways use high-strength asphalt to withstand long-term compaction from heavy trucks; anti-slip asphalt is used on urban roads to ensure driving safety in complex traffic environments. In residential areas, asphalt is used for community roads, providing quiet and smooth surfaces to enhance residents’ travel comfort; park pathways can use colored asphalt, combining aesthetics with anti-slip properties; race tracks use high-friction asphalt to meet the traction requirements for high-speed driving.
Even in special-requirement scenarios, asphalt pavements can adapt. For example, in northern cold regions, asphalt’s freeze resistance can withstand temperatures as low as -30°C; in southern high-temperature regions, asphalt’s deformation resistance can withstand surface temperatures above 60°C; in mountainous areas with many curves, colored asphalt can mark curves, and anti-slip asphalt can shorten braking distances. This wide adaptability makes asphalt surfaces the mainstream choice for global transportation construction.
Asphalt vs Concrete Roads
Strength and durability
Concrete roads are primarily composed of cement, aggregate, water, and other materials mixed and poured together. After the cement hardens, it forms a rigid structure with high compressive strength, typically reaching 30–40 megapascals. In areas such as airport runways and toll stations that must withstand frequent heavy braking, acceleration, and prolonged heavy loads from heavy vehicles, concrete roads can maintain good condition due to their high strength, with a design service life of up to 30 years. However, their rigid nature makes them relatively weak in terms of flexural strength. When subjected to foundation settlement or temperature stress, they are prone to cracking. Once damaged, repairs can be challenging.
Asphalt roads are constructed using asphalt as a binder mixed with aggregate, forming a flexible pavement. Their compressive strength ranges from 2.5 to 5 megapascals (at 20°C), which is lower than that of cement roads. However, asphalt roads possess excellent flexibility and fatigue resistance, enabling them to adapt well to minor foundation deformations. Under normal traffic loads, they can recover part of the deformation through their own elasticity, thereby reducing the occurrence of cracks. Under normal maintenance, the service life of asphalt roads can reach approximately 15 years. If high-quality materials and advanced construction techniques are used, the service life can be further extended, and repairs are relatively easy after surface wear.
Construction Difficulty and Schedule
Concrete road construction imposes strict requirements on subgrade flatness and moisture content, necessitating precise control of cement mix ratios, pouring, compaction, and curing processes. After concrete pouring, a curing period of 7–14 days is required to achieve sufficient strength before traffic can resume. During this period, continuous watering is needed to maintain moisture, ensuring full cement hydration. The entire construction cycle is lengthy, significantly impacting traffic, and urban road construction often leads to traffic congestion.
Asphalt road construction processes are relatively simpler. Asphalt mixtures are produced centrally at mixing plants, where quality is easily controlled. After transportation to the site, they are uniformly laid by paving machines and then compacted by rollers. After completion, the road can be opened to traffic once the surface temperature naturally drops below 50°C (typically 2–3 hours in summer). In urgent situations, watering to cool the surface can further reduce the waiting time, significantly minimizing construction interference with traffic, making it particularly suitable for rapid repairs or new construction on heavily trafficked sections.
Driving Experience
In terms of smoothness, asphalt pavement construction enables continuous paving without noticeable joints, resulting in a smooth and flat surface. Vehicles experience minimal vibration, and interior noise is significantly reduced, providing drivers and passengers with a quiet and comfortable experience; Concrete roads, due to the hardening properties of concrete, require expansion joints during construction. Vehicles passing over these joints experience vibrations and “clunking” sounds, which can cause fatigue for drivers and passengers after prolonged travel.
In terms of slip resistance and drainage, asphalt roads feature diverse surface texture designs that effectively increase tire-to-road friction, and they have excellent drainage performance. Porous asphalt can quickly drain surface water, reducing the risk of “hydroplaning” in rainy conditions. Concrete roads have relatively smooth surfaces, and while friction can be increased through methods such as engraving, long-term wear reduces slip resistance, and their drainage capacity is inferior to that of asphalt roads.
Environmental Protection and Economic Efficiency
From an environmental perspective, asphalt can be recycled and reused. In Europe, the recycling rate for asphalt reaches 87%. Recycled asphalt, after processing, can be extensively used in the production of new mixtures, reducing the need for new asphalt extraction and aggregate consumption. In contrast, cement production involves high energy consumption and carbon emissions, and discarded cement blocks are difficult to recycle, with most being landfilled, occupying land resources.
From an economic perspective, the initial construction cost of asphalt roads is typically higher than that of cement roads, but asphalt roads have higher construction efficiency, reducing traffic control time and minimizing indirect economic losses. They also have lower maintenance costs, with convenient repairs and shorter downtime. Cement roads have lower initial costs but require longer maintenance periods and more complex repairs, resulting in higher long-term comprehensive costs. For example, in residential area road renovations, asphalt roads can be constructed quickly with minimal disruption to residents’ lives, and from a full lifecycle perspective, their economic advantages are more pronounced.
Environmentally and Economically of Asphalt Road
United States
In 1991, the U.S. Congress passed the “Surface Transportation and Economic Act” (also known as the “Ice Tea Act”), which explicitly stipulated that starting from 1994, any project using federal funds to purchase hot-mixed asphalt mixtures must allocate 5% of the funds to recycled rubber asphalt mixtures, with an annual increase of 5% until reaching 20% by 1997. This act significantly promoted the use of recycled tire rubber powder in road construction. Between 1994 and 1997, the highway industry consumed waste tire rubber powder equivalent to approximately 400 million waste tires. This not only addressed the issue of waste tire pollution but also achieved resource recycling and utilization, reducing the procurement costs of new asphalt and aggregates, thereby promoting the development of asphalt roads from both environmental and economic perspectives.
European Union
The European Union published Regulation No. 305/2011/EU on March 9, 2011, which came into full effect on July 1, 2013, replacing the original Construction Products Directive 89/106/EEC. This regulation requires all construction products related to health, safety, and environmental protection (including asphalt mixtures, etc.) entering the EU market to be labeled with the CE mark. Additionally, companies are required to demonstrate the environmental sustainability of their construc
Japan
Japan actively promotes the application of environmentally friendly asphalt roads in road construction and has introduced a series of policies to encourage the use of environmentally friendly pavement materials such as drainage asphalt pavement. For example, projects that adopt environmentally friendly asphalt roads are eligible for certain fiscal subsidies or tax incentives, guiding construction entities to prioritize asphalt road solutions with better environmental performance. The application rate of drainage asphalt pavements in Japan’s highway network has exceeded 80%. Their excellent drainage performance reduces road surface water accumulation, lowers the incidence of traffic accidents, and extends road service life, demonstrating economic value from the perspectives of traffic safety and road maintenance. Simultaneously, they reduce water resource waste and pollution to the surrounding environment, achieving a win-win outcome for environmental protection and economic benefits.
Conclusion
Overall, asphalt pavements stand out as an excellent choice for road construction due to their significant advantages in driving experience, cost-effectiveness, safety, durability, sustainability, flexibility, noise reduction, construction efficiency, and adaptability. Compared to cement roads, while asphalt pavements may slightly lag behind in terms of compressive strength in certain aspects, they demonstrate clear advantages in key dimensions such as flexibility, construction duration, maintenance convenience, driving comfort, environmental friendliness, and long-term cost-effectiveness. They can better adapt to diverse traffic scenarios and climatic conditions, minimize disruption to traffic, reduce lifecycle costs, and achieve resource conservation through recycling and other environmental measures.
The introduction and implementation of a series of relevant regulations abroad have provided strong policy support for the environmental and economic development of asphalt roads. The U.S. “Surface Transportation and Economic Act” has promoted the use of recycled materials in asphalt roads, the EU Regulation No. 305/2011/EU ensures the green and sustainable development of the asphalt road industry, and Japan’s relevant policies have facilitated the widespread adoption of environmentally friendly asphalt roads. These policies not only allow the environmental value of asphalt roads to be fully realized but also further enhance their economic advantages, creating a virtuous cycle.
With the continuous advancement of technology, the performance of asphalt pavements will continue to improve. In the future, within the field of transportation construction, asphalt pavements will continue to play a significant role, leveraging their comprehensive advantages and policy support, to provide a more robust foundation for people’s mobility and societal development.
