Every industrial yard construction project begins with a geotechnical report, which identifies challenges and problems. These reports provide data regarding the surface being built on including soil strength, load size the soil can support and how water will affect the yard.
These are all important points to consider, as they can prevent common problems before they evolve into costly maintenance issues.
Common problems that arise when constructing industrial yards include:
1. CLAY EATS GRAVEL.
When wet, clay gets hungry and starts eating and absorbing gravel on the surface. Water in clay results in soil less dense, and constant traffic from heavy machinery will push a 2 – 8 inches of gravel cover into the clay base over time.
Dropping another layer of gravel on top of the “eaten” layer will eventually result in a “crust” on the surface. Although this might work for a while, eventually water can get under the crust and soften a yard, resulting in extensive, time-consuming repairs.
Solution: For yards with heavy traffic, a solid layer of gravel of one to two feet is necessary to avoid gravel absorption, and for yards with lighter traffic, an eight-inch layer would be an effective solution. Geo-textiles are a solution that should be used in many clay situations to create ground stabilization and to keep the gravel from mixing with the clay.
2. TRAFFIC FLOW AND HEAVY MACHINERY.
On a yard surface not properly prepared to handle constant heavy loads, heavy traffic may result in problems.
Solution: Initially it is important to analyze all factors – traffic flow, types of machinery, frequency of loads – in order to determine load per square inch.
In areas expected to carry heavier traffic, a solid base and thicker layers of gravel will be required. Again, a layer of a foot to two feet of gravel is recommended. It is surprising how quickly gravel can disappear into the soil in heavy traffic areas.
3. WEATHER PATTERNS.
Constructing a yard is similar to baking a cake. There is a formula for moisture content in both and if it is not perfect, the yard will not settle properly just as the cake will crumble. A yard either too dry or too wet will not pack as quickly or as solidly as ground with the right moisture content.
Solution: Consider the season in which you will be building. Earlier summer, when spring moisture is still present in the soil, might be the ideal time to build.
Geogrids: An Innovative and Comprehensive Solution
Geogrids help distribute load weight and are being used more frequently in industrial yard construction. Essentially, once the ground has been packed, a geogrid is laid over the surface, and gravel is layered on top. The grid distributes pressure more evenly across the surface. For example, instead of pressure being applied to one square inch, it is spread over a three-foot radius.
Grid offers improved yard stability and strength, while preventing higher moisture content in the soil by improving proper drainage.
Geogrids are an excellent solution to industrial yard issues, and have significantly contributed to a longer life span in our yards.