According to a 2011 Office of Fair Trading report, aggregates are a vital part of the construction industry with a turnover of £1.4bn on an annual basis. Most new building sites require a constant supply of aggregates for a number of different purposes, ranging from pipe bedding through to creating level surfaces for driveways and roads.
If you’re a merchant looking at supplying the industry with aggregates, what are the best and safest ways to store these materials?
When storing aggregates, the first thing to consider is how much space is needed for the stockpile. This can usually be calculated by looking at the amount of aggregates that are sold on a weekly or monthly basis and how often new stock is delivered to your unit. You may want to keep a slight excess of your most popular aggregates in order to deal with any unseen problems that could occur in the supply chain, allowing you to supply your customers if there are any delays in delivery. The last thing you want is your valued clients going elsewhere for their supplies, which could damage your hard-won relationship. By carefully designing your aggregate storage, you can prevent difficulties occurring when these materials need to be moved, ensuring that there is always a good mix of particle sizes throughout your aggregates.
Risks to personnel
UK Health and Safety law says that you must conduct your business without putting either the public or your workers at risk. There are a number of dangers associated with storing aggregates, the most noticeable of which is the possibility that a stack could slide and crush or even bury a person. It’s therefore of paramount importance that you make the correct provisions to ensure that your aggregate stores are secure and stored away from the perimeter fences of your premises.
One way in which aggregates can be stored safely is in storage bins. These should have bottoms that slope towards the front of the container, allowing the aggregate to move in the bin, so it can be easily collected. You’ll also want to avoid angular corners as these can often trap aggregates, making it difficult for the material to be removed from the bin. Try to keep bins as full as possible in order to ensure that there is an even mix of particle sizes throughout the aggregate.
It is important to make sure that aggregates are unloaded in the correct manner to ensure that a good stockpile of material is formed. It is therefore vital that each consignment of aggregates is dropped in the same place to form a pyramid of material with the weight distributed around the bottom of the stack, which should help with the unloading process. It is also vital to ensure that aggregates are not being unloaded from a high position as wind can scatter the smaller particles away from the stack. Once the aggregate has been unloaded into a conic pile then you may want to flatten it out into a single layer, as this will stop smaller particles from running down the stack where they can collect. Equally, if you’re moving aggregate from a stockpile into a storage bin, make sure that you always load the bin directly from the top, as this will prevent the material from segregating into different-sized particles.
There are a number of ways in which your aggregate stockpile can become contaminated. These range from cross-contamination between different types of aggregates through plant material, such as leaves or even weeds growing in the stack, mixing with the material. It is even possible for contamination to occur if a bin that’s used for storing an aggregate of one particular size is not completely emptied and cleaned before being used to store a different aggregate. It is important to make sure that you have a clear policy around contamination, storing your aggregates on hard pallets or bases that have good drainage and are non-water permeable. This is an especially useful practice if you are using mechanical loaders to move aggregates, as it will prevent them from scraping up ground dirt with the aggregate. Keep your piles of aggregates far enough apart to prevent them mixing with one another – you may even wish to put barriers in between different aggregates to prevent them mixing.
It is important for some aggregates to be stored in a moist condition. Typically, most aggregates that are stored in a stockpile or in a bin will need to be kept slightly wet, with the material containing both surface moisture and water within the aggregates’ particles. This will prevent loss of aggregates where the finer particles can turn into dust and can easily becoming dislodged from the stock by the movement of air. The simplest way to ensure that the moisture content is constant is by sprinkling the aggregate with water at regular intervals to keep it constantly saturated. Where necessary special probes can be used to ensure that the moisture level within any aggregate stack or storage bin is at an optimum level, although these will work better with finer aggregates that coarse particles, which can damage the probes.
Finally, one of the most important things to consider when storing aggregates is your attitude. It is essential to make sure that workers adhere to all policies and procedures at all times to ensure that your aggregates are always of a high quality and that they contain a good mix of different-sized particles. It only takes one break in procedure to damage the integrity of your aggregates, which can have harmful effects for your business if this in turn spoils a relationship with one of your clients. By staying vigilant and making sure that all members of your team know exactly what they need to do with regards to the storing of aggregates, you can stop such a situation from ever occurring.
Lee Newell is the marketing manager at ESE Direct, a UK supplier of products for business and industry.