FREE TRAINING FEATURE

FREE TRAINING FEATURE

Want to learn more about pavement management, in-place recycling, and pavement preservation? Do you feel like you're setup for failure as an agency engineer with little or no money to spend on your roads? Enter your email below to get free instant access to a two-hour video-training session that Blair did for the Northwest Pavement Management Association:

Better Roads Radio

Listen to Stitcher
LinkedIn

More Articles available on LinkedIn

Blair Barnhardt

Slurry Seal

The principal materials used to create slurry seal, as stated by the ISSA, are aggregate, asphalt emulsion, and filler, which are mixed together according to a laboratory’s design-mix formula.  Water is also added for workability.

Asphalt emulsions serve as a binder holding the crushed aggregate together and adhering the new slurry surfacing to the old surface over which it is being applied.

The aggregate must be clean, crushed, durable, properly graded, and uniform.  The asphalt emulsion is a three-part system consisting of asphalt, water, and emulsifier.  Fillers such as Portland cement, hydrated lime, or aluminum sulfate liquid are often used in small quantities as stabilizers or chemical modifiers.

In the early 1930s, a coating consisting of a mixture of very fine aggregates, asphalt binder, and water was laid out on a road in Germany.  It proved to be a novel approach, a new and promising technique in maintaining road surfaces, and marked the beginning of slurry seal development.

Later in that decade, extensive worldwide experimentation began in earnest.  But it was not until the 1960s, with the introduction of improved emulsifiers and continuous flow machine’s, that real interest was shown in the usage of slurry seal for a wide variety of applications.

Continuing advancements in mixing methods, emulsions and machinery have made slurry seal today’s choice in providing highly durable, low cost paving and surface maintenance.  As a treatment for everything form residential driveways to public roads, highways, airport runways, parking lots, and a multitude of other paved surfaces, slurry seal is now used extensively throughout the world.  Local, state, and federal agencies – including the military – have a growing and ongoing commitment to the use of slurry seal in their maintenance programs, attesting to its effectiveness and economy.

It is worth noting that with polymer modification a slurry surfacing that would normally take 3-4 hours to set up can set up in 2 hours or less.  Where a quicker set time or stacking of the stones to make a thicker lift is required, the owner agency should specify Micro Surfacing.

Why Use Slurry Surfacing?

Slurry seal maintenance dramatically extends pavement life.  Although the serviceability of an untreated asphalt pavement is still adequate after several years of use, pavement deterioration has already begun.  A slurry seal maintenance program undertaken before significant pavement deterioration has begun is essential to proper pavement maintenance.

As the most versatile of any pavement surface treatment system, slurry seal is also unique in its ability to deposit a durable bituminous mixture in accordance with the demands of a variably textured surface – filling cracks and voids, sealing weather-tight, and providing color and texture delineation in a single pass.

Slurry seal is very economical to install and highly cost effective to use.  It is also a easy and swift application process with makes slurry especially attractive for rehabilitating busy thoroughfares, parking lots, and airport runways.  The new surface is ready for use just hours after application.

Existing distresses in older pavements – surface cracking, raveling, loss of matrix, increased water and air permeability, and slipperiness due to flushing and aggregate polishing – can be corrected through a slurry application.  Waterproofing is also achieved, preventing further deterioration.  An all-weather, long-lasting surface is created that offers skid resistance and improved handing characteristics for drivers.

With one simple application existing pavement receives a new wearing surface of uniform black color and texture.  Enhanced appearance means increased property value, marketing potential, and buyer acceptance.  Thoroughfares, shopping center parking lots, and other public or commercial pavements treated with slurry seal become more attractive and eye-appealing.

Even the best of surfaces are subject to the wear and tear caused by time, weather, and traffic.  No surface is permanent.  By undertaking a program of planned pavement maintenance considerable savings in rehabilitation costs may be achieved.  Your pavement surface will remain sound, usable, and safe.  Extensive downtime needed to repair deep cracks and potholes will be reduced or eliminated.

The application of slurry seal will significantly extend the life of existing pavements by protecting the under surface from damage caused by water seepage.  Improved surface performance is an added bonus.  A pavement maintenance program using slurry seal will not only help to protect your pavement, it will help to protect your paving investment.

Slurry in a residential area

Slurry in a residential area

Slurry in a residential area

Slurry in a residential area

Handwork slurry

Handwork slurry

Structure protection during slury or micro-srufacing

Structure protection during slury or micro-srufacing