Soil Compaction Equipment

Every construction project needs good soil compaction; it enables the required solid base to support footings and foundation. In situations where the soil base is not reliable enough, different kinds of problems may arise, such as cracks and leaks, slabs cracks, and foundation erosion. In other to know the type of soil and its level of the basement, there are lots of solutions or alternatives to it, such as compaction equipment. Getting the right ground compacting machine is essential; it will help you compact soil and make it ready for use. The kind device you would use must have at least the following two main criteria. The first criterion is to get the right machine for the kind of soil you want to compact; the second criteria are the quantity of material that needs compaction.

The first and the second criterion required should be able to give the amount of force needed while the second criterion determines by the size of the machine needed to deliver an adequate job.


Soil type: there are different kinds of soil with different characteristics; this is what determines the density and optimal moisture content of the land. These soils are determined by grain size; this grain size is identified from the use of various progressively finer sieves. However, grounds well-graded feature a wide range of small particles; these tiny particles are what help to fill up voids between larger ones; these kinds of soil are easily compacted because they already have a suitable dense structure. 


According to the American Association of State highways, there are 15 different kinds of soil groups; those groups are in three broad categories namely: the cohesive, granular and organic soil, they also made it clear that only the first two out of the three clarified kinds of land can be compacted. 


We can understand that the cohesive soil is the one that only comprises of smaller particles, these smaller particles range from 0.00004 to 0.000 inches, and they are tightly bonded together through the molecular attraction. Naturally, they are dense, and this compact nature is the reason why you can’t easily view separately. You can use water to wet and mold them; they are easily molded and become hard when they dry. 


The second category, which is the granular, falls in the groups of the popular sand and gravel we used to see. Their size ranges from 0.003 to 0.08 inch; you can size them to medium size of 0.08 to 1 inch. You can hold and view them individually, and the soil feels gritty when rubbed among fingers. They don’t keep water to themselves unlike the earlier explained kind of land. Let’s now take a look at the compaction specifications of these soils.


Compaction specifications

When carrying out a project, the soil meant for a project is expected to attain a certain level of compartment agreed by the site engineer. A soil sample is generally measured with a soil texture instrument called ASTM1557; the device is mostly used to know the characteristic of the soil sample that is subjected to compaction forces when examined in the laboratory. The process of soil examination in the laboratory is called proctor or modified proctor; this process requires that the contractor meets up with a percentage of between 90-95% before soil can compactable enough for use.


Compaction machines

Compaction machines do no other works than to increase soil density. Some among the said machine apply static forces like pressure and kneading generated from the dead weight and configuration of the compaction machines. However, here are three primary compacting machines used for soil compaction.


Rammers: this is a machine configured to jump and move forward as it tries to make compaction on the soil, applying massive force generated from small gasoline or diesel engine that powers a piston with two sets of springs. Rammers have a relatively small footprint controlled by an operator when in use delivering a high-amplitude frequency blows of between 500 to 700 vpm.


Vibrator plates

This machine is not as powerful as rammers but produces an amplitude-frequency ranging from 2500 to 6000 vpm compactable for granular soils. The light-duty tool is made of a plate width of between 14 to 20 inches; it is also available in bigger sizes with bigger vibrator plates made to produce more compaction forces on semi-cohesive and granular soils. Its plate width is around 16 to 28 inches wide.



Rollers are the third kind of compacting machine available for soil project compaction. It is a walk-behind and ride on model soil compacting machine suitable for both mixed and granular soils specially made for larger areas such as parking lots, driveways and roadways. It releases a high frequency of forces of about 400vpm. It comes with padded rollers also called trench design mainly to compact cohesive soils often used in confined space of utility trenches.


Rollers are powered by diesel engine and use either of hydraulic or hydrostatic steering and operation it home unit in it controlled with remote control.


Compaction trend and innovations

When looking to get a compactor machine, it is essential to look out for the ones that reduce the transmission of machine vibrations to the operator’s hand and arms. The vibration produced by the machine can cause harm to the operator and result in a body strain injury called Reynaud’s syndrome. The damage usually leads to finger tingling, numbness, loss of sensation, and loss of muscle control. In the developed countries, strict policies are on ground to control the use of compacting machine so that this injury will not become a norm in the society such that devices that have vibration control are only in circulation.


However, there are now some modern compacting machines that have a sensor; this sensor is used to know soil stiffness and help to know compaction progress. It is so effective such that it gives real-time feedback that helps to see the level of compaction development and prevent over compaction that is capable of wasting time and fuel.  



How to  Choose the Right Compaction Equipment


The reason why there is need for compaction is to lay a good foundation for a construction job, so that the project about to be layed can have a good base. However, the compaction equipment needed is of different categories and usefulness. The most common and relevant soil compaction machine is trench rollers and rammers, but there is need to consider the following factors if you really want to end up with a perfect job simply by using the right compaction for your job.

However, we need to understand that the major reason why we are compacting the soil is to apply force to the soil so we would be able to remove air voids from the ground so that we can arrive at a soil texture that can hold greater weight. Compacting soil mechanically helps, the natural process of soil compartment, making construction easy particularly on marginal sites.

Identifying the soil is the best step to take when trying to determine the best equipment needed to arrive at a good compaction results because soil is clarified into two categories which are the granular and the cohesive.

The granular type of soil consists of only sand and gravel, sand and gravel are the kind of soil that is coarse and big in size for easy identification. At any time a granular soil is wet, it can be easily moulded and this will make it crumble easily. They are easy to compact as they crumble easily during compaction; the best kind of machine used for such soils is vibrator plate or vibrator roller. The vibration process helps to reduce the frictional forces at the contact surface thereby allowing particles fall under their own weight.  As soil compactor starts to vibrate, the soil particles begin to separate from each other allowing them to turn and twit until they are able to find a movement that stop them from further twisting and turns.

Cohesive soils are soils that fall in the categories of silts and clays, they are soil particular that are soft when you hold them and can be easily rubbed within hands. If you find cohesive soil in a wet condition, they can be easily moulded into any shape of your choice. However when the cohesive soil is dry, it they are mostly difficult to crumble and they are best compacted by impact force. The best machine for this kind of soil is rammer or sheepsfoot, when you use either of these machines on the soil. It pushes out air and water from within the particles.   

In situations where you have a project and do not know the kind of machine that will be suitable for its use, you can make use of a jobsite website for specifications. There is always a specification to come up with the use of this website, but the most common and regular specification includes a percentage of proctor density needed to achieve optimum compaction. If the machine is not powerful enough to handle the job, the proper density will not be reached and if the machine is too powerful for the job it will definitely result to over compaction.

Even as we know that the jobsite is the best place for us to know the right compactor for a particular job, we also need to understand that this compactors are more effective than each other. In reality, vibrator plates are more powerful and effective than rollers, because of how its baseplate spread around the ground while in use. The difference between vibrator plates and rollers is that, vibrator are easy to maneuver while rollers are only useful in areas where there is enough land to move around and has high travel speed. However, this same logic applies to rammers. Rammers are mostly applicable on cohesive soils and they are easy to maneuver while trench rollers are to be used in large trenches and in open areas.   

Safety measures

Ensuring safety on a job site is more important than any other thing. The reason is that, implementing proper measures and safety care on your job site is paramount to your success. One of the best ways you can ensure safety on your job site as an engineer is to make safety equipments available for use.

A standard job site does not lack the two following two control signals, the radio frequency and infrared. Radio frequency control is very effective, it does not necessarily require that the machine should be within the sight of the operator which is supposed to be a dangerous idea but the operator also have a monitoring devise that helps in knowing the present position of the machine.

The second safety measure equipment which is infrared is developed by a great engineer Wacker Neuson. This safety measure implies that the operator maintain a visual contact with the machine at all time so as to know the present job position of the machine. The initiator of this infrared also configured the devise to be able to use reversible plate options because infrared do not rely on radio frequency to perform and the risk of interference with other equipment on the jobsite in minimized.

How safety and productivity works hand in hand

The modern way productivity is ensured on jobsite nowadays is now beyond the mere protecting the operator from minor accidents. Several jobsite safety measures are now in place, operators are now getting more protection from noise and hand and arm vibrations and exhaust. More safety laws as well as engine emissions are now the talk of the town in the engineering construction field. Renowned contractors are aware that safety is part of machine selection as it is one of the most effective tools that improve work rates and productivity.

However, as a project engineer, it is important that you should use your level of experience in the construction field to put the necessary equipment on ground for good work delivery so as to arrive at a good level of work success. Make sure you are buying the right equipment for your jobs and place your engineers under the right safety laws.