Asphalt, The Main Material for Road Construction that is Temperature Sensitive

Asphalt is one type of material that is important for road construction, having adhesive properties that prevent it from deteriorating quickly. Another characteristic of this material is its deep black color, resistance to water damage, and its viscoelastic nature.

Originating from nature, usually from the processing of petroleum, asphalt is indeed one of the natural resources that is quite expensive. The materials contained are very complex, including saturated carbon, aliphatic, and aromatic compounds.

Functions of Asphalt

There are reasons why asphalt is a necessary component in the construction of highways, especially as it is used as the final component placed on top of the road. This is because asphalt functions as a prime coat and tack coat to ensure that each material used in road construction adheres to one another.

This function makes the material waterproofing, thus protecting the materials beneath it. As a result, roads do not deteriorate quickly even when exposed to water abrasion, such as during rain or flooding.

The nature of asphalt is actually liquid, my friend, although when placed at room temperature, it becomes a thick solid. However, the original property of this material is liquid, allowing it to fill empty spaces during road construction, thus acting as a filler between other materials and making the road stronger.

Properties of Constituent Materials

At first glance, it has been explained that the property of asphalt is viscoelastic with a complex composition of chemical materials, with the highest carbon content, which can reach up to 88%. The remaining components are hydrogen, sulfur, oxygen, and nitrogen.

From these chemical components, asphalt has 4 main properties, my friend. The most prominent property is asphaltene, as this is what makes asphalt a suitable material for road construction because it makes it hard and thick.

You must have heard the term resin, right? Resin is actually one of the compound properties in asphalt, my friend. It is dark brown, solid in form, and contains carbon and hydrogen compounds.

Aromatic and saturated are the next properties in this road construction material. Aromatic is dark brown and is a thick liquid that makes asphalt often appear solid at room temperature. Saturation is the opposite of resin because it has a non-polar form with alkyl naphthene compounds inside.

Properties of Asphalt as Road Construction Material

If the properties of the constituent materials for road construction explain more about the forms and compounds that make it difficult to understand without a chemistry background, the inherent properties of asphalt as a material itself are certainly easier to study. Because these properties are quite common.

The first property of this black material is its undeniable durability. This durability is what allows asphalt to maintain its shape despite changes in weather.

Cohesion and adhesion are other main properties of asphalt. They bond with each other, ensuring that the compounds within are strongly bound. This material is also sensitive to temperature, thus maintaining its shape according to the existing conditions.

The most well-known property of asphalt is its hardness. You must have never seen a road that is soft after being built, right? Unlike roads that are just layered with soil. Thus, it can support vehicles of any weight.

Various Types of Asphalt

An interesting fact about road construction using asphalt is that different regions will use different types of asphalt, my friend. For example, in Buton Island, Southeast Sulawesi, natural asphalt is more commonly used. This type is also used for road materials in France, Switzerland, and the United States.

Other types of asphalt include residue and polymer. Manufactured asphalt is a residue from petroleum distillation, thus it has properties similar to the petroleum used. Therefore, its properties will certainly follow the distilled petroleum.

Polymer asphalt is one type with materials derived from the modification of natural and synthetic polymers. This modification has been developed over the last few decades and has been well tested.

Quality Testing Parameters

Usually, before determining whether the road construction material is good, it must go through a long testing phase, my friend. More precisely, there are 8 testing stages to determine whether the material is suitable for a certain area and can last for a long time.

Asphalt will be tested for its hardness properties, commonly referred to as the penetration stage. This important property must be known to determine whether its quality is good enough to be the outer layer of a road.

Its specific gravity must also be known to understand the petroleum content contained. The higher the specific gravity, the more petroleum content there is. How well asphalt can adhere to another material must also be tested to know how durable the road will be.

One thing that must be clearly understood about this material in testing is the flash point and fire point. Roads often experience friction and will increase in temperature during the dry season, so the flash point must be well understood to avoid danger for road users.

The softening point, solubility, and ductility are the last three aspects that must be tested for asphalt to be used. If all eight tests yield satisfactory results, the asphalt passes and can be used for road construction.

Tips for Strengthening Road Construction

To ensure that the constructed road is durable and does not incur high costs due to rapid deterioration, there are several tips that can be learned, my friend. This knowledge can help you monitor whether a road construction project will be durable or not.

The first tip is to know the thickness of the asphalt used. This can easily be determined by observing how many times workers pour the thick black liquid on the final layer of the road. According to regulations, the minimum thickness is 15 cm to ensure that vehicles passing over the road remain safe.

The slope of the road also affects the durability of the highway, my friend. However, in reality, roads are not built flat, and this is a common road construction technique. Why? This is because roads often deteriorate quickly due to water pooling in the middle if the road is flat. Therefore, workers will usually make the sides sloped to allow water to flow off the road.

The drainage system also plays a role. A good asphalt road layer requires a good drainage system. This will relate to the selection of appropriate materials and types of road construction materials to prevent sinking even shortly after construction.

That is a detailed explanation about asphalt that we often see on the roads. Now, you must understand why sometimes we smell unpleasant odors from newly constructed roads or why asphalt must be used as the final layer in road construction.

Author: Nisa Maulan Shofa