How to do excavation in Construction

Excavation work basically contains excavating earth and getting out. What this means is that you have to take the soil out and throw it at a distance far away. In Site Engineering you have to remove excess earth from your construction site before you can do anything, You have to dig to get to the ground level before you start your construction, and even after that you have to excavate further down to get to the foundation level.

How to do Excavation

You will either use a machine or manually dig the soil, with a Total Station or an AutoLevel you will note the levels of ground before and after excavation. You will use these levels when calculating the amount of earth excavated (It is important because this is how you know how much to charge the client)

You will also momentarily halt excavation to check levels with an auto level, this way you don’t over excavate. If you dig more, you have to fill it up and you won’t be paid for the extra work( because its your fault for digging extra and you won’t be paid to correct your own mistake ).

We have to excavate in a way which allows workers to do construction jobs safely. If you are digging up to 2 meter you can basically go staring down. But if you have to dig more than 2m you either have to dig in a slope of steps.

Stepping Excavation

For Stepping excavation every 2 meter from the bottom you will provide steps of 50cm.

What this means is if you have to dig up to 5m below ground level, 5 meter is 2+2+1, so you will have 2 meter from bottom then one step of 50 cm then another 2m above that and a step of 50cm and finally 1m at the top.

Obviously you are going to dig from the top, but you plan from the bottom so you know how much you have to dig extra at the top. This allows the walls of the trench to be sturdy.

Sloping Excavation

For Sloping Excavation you dig with a slope of 1:4 ( 1 Horizontal 4 Vertical ), what this means is that if you have to dig up to 5m you will dig 1.25m(one fourth) extra around the perimeter at the top.

Filling

Soil you use for filling should be free from roots, grass, shrubs etc.

you will fill in layers of 20cm with soil and them consolidate it with half tonne roller, and every 3rd layer should be compacted with a roller of 8 tonne.

Now you know how to do excavation and filling, and you also learned the importance of Total Station and AutoLevel in excavation. That is why these two are the most important surveying instruments, and every site engineer must know how to use them. If you want to learn Total Station I highly recommend you use the official Total Station Tutor App