The Importance of Site Testing – CBR Testing

Written by Henry Young. Posted in Education & Training

Everyone knows how important safety is in general. Well, it is just as important in the field of constructions where nothing has a bigger impact than quality. No matter is it about the soil, the equipment used or the materials involved, one should handle with care whatever is happening on a site. This is the reason why site testing is one of the first things you will have to do before starting to work. Not many people know about the California Bearing Ratio and what its use is in the vast domain of constructions. CBR Testing actually refers by definition to the relation of part to whole between force and unit area needed to penetrate in the soil with a certain device (a specific plunger with a 50 millimeter diameter). This may sound complicated, but in reality what this procedure does is finding out if the natural ground one wants to build on is resistant enough for the activities that will undergo here. Now that you understand what CBR Testing it’s all about, you might want to know a few reasons why it is paramount to use such services for your purposes. You might want to check STS construction for more information about this topic.

First of all, when you are making the required preps for a construction project, there should be one specific step most people forget to take into consideration: the basic structure of the building or the railroad which needs to be built in a certain place demands a specific type of soil resistance. Knowing that, you cannot guess the type of soil your site is placed on, reason for which you will need to apply for CBR Testing. Of course, for this kind of testing there will surely be prerequisites such as acknowledging the degree of saturation of the respective soil area (given the fact that water content highly affects the soil material) and knowing the exact history of construction operations there. If the soil has been modified in any way, the results of the test will probably be altered. Invalid results could trick you and make you believe the soil is either appropriate when – in fact – it is not, or the opposite. This is why gathering as much information as possible about the area you are going to place your construction site to should be done prior anything else. The main benefit of CBR Testing is that you will receive information about the soil strength. This is decisive especially if the construction that is going to be put together there necessitates a certain type of soil with specific characteristics for ensuring safety matters to the future users of the place.

 

You may be wondering what kind of data you will be given after a CBR Test is performed. Penetration, proving ring dial reading, piston load, area of piston and the penetration stress will be included in a data sheet. Along with it, a test report which will state what the moisture content is and what the dry density is will offer precious information about the soil and whether the terrain is ready for holding a construction site or not. After you will be given this information and everything seems on point you can start developing your future plans.

 

Having a mere idea about soils and what’s there to be taken into account about them might help you understand how far-reaching site testing is. CBR Tests are also purposed for measuring the strength of subgrade soils, sub base and base course material when building roads. Now, railroads are meant to be extremely safe and stable through time and the California Bearing Ratio was implemented by Caltrans just because of that reason: to ensure the security of construction sites purposed for transportation. One wouldn’t like putting the life of others in danger because they overlooked such an important factor as testing the mechanical strength of subgrades and base courses and that’s why testing exists. Plus, the relevance of such tests often result in them dictating the actual thickness of pavement and the component layers involved in its construction. The bearing capacity of the soil you are going to obtain from CBR Testing is the main index you will be following through the entire period of the existence of your construction site.

 

The sample that is going to be taken away can be found in two different states: undisturbed (which is obtained by simply cutting mold from the file soil) and remolded (which is obtained by preparing the sample for optimum CBR results). After the sample has been prepared, there will be several steps towards obtaining the testing results. First of all, the mold will be going through a dynamic compaction process which will give information about bulk and dry density of the soil. Also, static compaction will offer the client data about ideal/required water content in order to obtain a certain density. The next step would be soaking which is used to precisely calculate the percent swell (here the change in length during soaking and the original sample length are being compared). Finally, the penetration test will offer data about stress applied and maximum load supported. In the end you will be obtaining info about the optimum moisture content, density, weight, volume and penetration. The final CBR value will be calculated by comparing the corrected load value with the standard load and penetration.

 

You surely might think that the process for obtaining this kind of data is difficult – and it actually is – but you have nothing to worry about given the fact that professionals are doing this job for you. All you need to do is contact a specialized company in this field and make good use of the services they provide. Construction sites need to be tested at all costs to avoid further complications and you should keep that in mind each and every time projects appear in your path. Safety and time-resistance are two concepts that you definitely don’t have to play with.