Basic machinery required for executing General Construction Work, Structural & Equipment erection
I’m writing this blog to not only to help my readers refresh their information but also to refresh my own information as I’m also a civil engineer and need to keep myself updated on machinery being used in construction projects.
Most of the big companies who can afford to give training to their employees (both on regular roles & hired from contractors) give training to their employees to add their information by means of refreshing courses on the information already learnt and on the information on new technologies which comes in the market on time to time. Continual improvement is the first mantra of success in construction industry (for that matter anywhere & in any industry).
In this article I’ll be restricting myself to the name and few functions of equipment used in construction industry as I’m not an automobile engineer nor directly involved in the plant and machinery department of my company so I’ll not go in details of maintenance of equipment or comparison of various brands of equipment. Though at many places I’ll use the brand name but that is only because I’ve used those brands and am not aware of many- many others. Also this is not a paid article so there is no advertisement of any brand. This can be taken as disclaimer of this article and any article which I’ve written or shall write.
Now, coming to the main point: We construction engineers knows the importance of plant & machinery (shall refer as P&M now onwards) very well, out of 4 M – Men, Machine, Material, Money & 1 T – Time, this is one of the most important resource which at execution level helps us in achieving our targets. All others are equally required for successful completion of target.
The resource required in construction project can broadly be categories & grouped under the group of activities. Still, while planning we should understand and consider that few equipment are used at many locations under many activity groups for example a Hydra crane is used at reinforcement yard, structural steel yard, lying of pipe lines, small erections, shifting of concrete pumps for a smaller distance etc. all the activities are actually grouped under different heads. Similarly a Weigh Bridge is used for all materials required to be consumed under different activities and are to be procured on weighment basis for example aggregate, coarse sand, cement for concrete, reinforcement steel, structural steel etc. so while planning for deployment of P&M in a construction project we have to be very careful while allocating the resources to each activity and ensure that no surplus equipment is being deployed which may be rendered idle after a small use and hence increase the cost of P&M deployment.
I’ve also kept the scope of this article
Grouping of P&M based on activities:
Activities are grouped based on the similar nature of activity type and here in this article I would be taking reference of CPWD item master & specifications which is already an established standard and is invariably applicable for all type of construction projects.
Earthwork the most machine oriented group of activities where almost 98% of work if performed by machine will result in economical cost and for large projects this is very well possible. Labour is required only for dressing of the final layer need to prepare the base for PCC concrete or at the most the small drains where using excavator is uneconomical or not feasible due to its size & location. Earthwork require many equipment few of them are listed here:
- Excavators or shovels – There are two basic type of hydraulic excavators depending upon their type of dragging (excavation) action. Front Shovel have their dragging action in upward direction, backhoe have their dragging action in a downward direction and are mainly used below natural surface such as trenches, basements and deep excavations etc.. They are generally rated based on the bucket capacity and reach. Also identified based on wheel or track mounting. The location of use of the same is also dependent on the location & feasibility of the work. Common commercial names are L&T-Poclain, L&T Komatsu, Samsung, Tata-Hitachi, JCB etc. categorized as.
- Wheel Loader is also a type of wheel mounted front hoe used for digging and loading of loose material like earth, aggregates etc. not a specific to excavation only machine.
- Trenching machine – For shallow trenches
- Draglines – for excavating earth for drainage channels and building leeves where water is present.
- Clamshell – for lifting material vertically
- Hauling Machines – Trucks – are used to haul the material excavated by shovels / excavators. The capacity of a truck / hauling unit can be expressed in tons or cubic meter.
- Scrappers – Used for excavation & hauling of earth for highways, airports, dams, canals and levees.
- Earth Shapers & Compactors – For compacting earth in fill.
- Sheep’s-foot roller
- Static roller
- Dynamic roller
- Drilling machines for rock blasting – Drill machines are used to either break the small lumps of rocks or drill a hole in them to receive the blasting material for blasting of rocks.
- Bulldozer – is an equipment with a substantial metal plate (known as a blade) used to push large quantities of soil, sand, rubble, or other such material during construction or conversion work and typically equipped at the rear with a claw-like device (known as a ripper) to loosen densely compacted materials.
There are many more machines but I’m restricting myself to this list for time being here as they are the most commonly used machines at general construction project site.
Concrete production and placement machines – used for production of concrete under controlled conditions, transporting, placing it to location by many means and compacting to achieve the desired density and even flow using the vibrators.
- Batching Plant – as the common name for batch mixing of concrete ingredients to make concrete. Batching plants are classified based on their capacity of production and the type of mixing drum they have but most commonly by the capacity viz. 10 Cum per hour, 20 Cum per hour, 30 cum per hour, 60 cum per hour etc.
Water chilling plant; Sand screening plant; Cement Silos to store cement for direct feeding of cement into batching plant pan / drum; Conveyor system to take material from bins to feed hopper to take it further to mixing pan / drum; Aggregate Bins to store aggregate’s minimum stock nearest to the batching plant so that conveyor can drag the material to hopper.
- Mixer Machines – The concrete mixing is also executed / achieved by other machines like mixer machine designated as 10/7 or any other nomenclature based on the capacity of production they may have load cell attachment to weigh the ingredients or may be used for volumetric mixing of ingredients as this is the method not very much acceptable for mass concreting and where concrete using mix design is mandatory so have not covered much details here.
- Transit Mixer – used for transportation of ready mix concrete a vital machine to take concrete from the batching plant to the location of placement.
- Concrete Placement using pumps & Boom placers – They are different machines to serve the same purpose – concrete pumping & placement. Concrete pump as most commonly called are stationed at one location near concreting location and then a pipe line to carry the concrete to its exact location is laid which is used to take the concrete. Whereas the Boom Placer is a machine which is truck mounted, movable and has the pipe line flexibly attached to the pump which can be maneuvered as per requirement. The stationary pump with pipe line attached can be used till great heights whereas Boom placers has the height limitations restricted to the pre-attached pipe line.
Concrete pumps are also identified based on their pumping capacity and movability very commonly.
Though there are other aspects for identification for each machine but we are restricting ourselves to the common use and common nomenclature being used by general civil engineers.
- Lifting concrete using winch & hoist – A more common method being used in building construction where the small batching plants or big capacity concrete mixer machines are being installed at the location of concrete itself and the mixed concrete is then directly poured into the bucket of hoist.
- Concrete Vibrators – A very important tool used at the time of placement of concrete. A concrete vibrator is used to consolidate freshly poured concrete so that trapped air and excess water are released and the concrete settles firmly in place in the formwork. So while planning concrete activity ensures the additional availability of concrete vibrators lest you may have to stop the activity in case one gets breakdown and there is no other alternative available. There are many type of concrete vibrators commonly referred based on type of fuel i.e. Electrical or Diesel and thickness of needle i.e. 20mm or 40mm or 60mm etc.
Again restricting myself here with the list shared above.
Form Work & Shuttering – there are many methods of formwork and they are also part of the Plant & Machinery as suppose in the case of slipform system Jacks, climbing rods along with shuttering plate etc. is used still we’ll cover those things under the section of formwork & shuttering and for time being excluding the same from the scope of this article.
The article is actually part “1” of the series of articles on P&M I’ve planned to write or arrange good P&M engineers to share their experience of the machines used in construction industry. Hope that in next article I can cover plants, machines or tools related to form work, reinforcement & structural steel and separate article on specialized machines like piling, tunnel boring machine etc.
then in next to that a complete list in the tabular form for the various Plant & Machinery being used in construction with a small narration about their usage.