An app that helps you calculate & transfer levels using an Autolevel or a Dumpy level.
The app is a calculator that requires inputs such as TBM RL, HI, Staff reading, Required levels, and based on the inputs it provides the current level and how much you need to elevate or depress the staff to get the desired level.
How to Use:
With reference to the image above, follow the steps:
- Enter a TBM RL, that could be established from the contour survey on your site.
- Once your instrument is set up, just backsight the staff that is held on the TBM or station point that you'd like to make a reference. Enter the BS Reading in the field and then hit the "Compute HI" button. This'll calculate and display the height of the instrument. (it is the axis height of the instrument, collimation height)
- You would be having a level that you need to transfer, on my site it was 97.7 as the footing top so I would enter 97.7 in the required level field. Then click on "Calculate Staff Reading Required".
- This will then display the staff reading that you should have if you want the required level.
- Now, sight the staff at the location which you want to check the elevation and type the visible reading and click the "Calculate Difference" button.
- The app will then calculate the difference and the RL at that location. It will also give prompts like if you should excavate more or you'll require some filling in that location by Depress or Elevate as text adjacent to the difference.
The best part is that it holds the values of TBM RL, HI, BS, Level required and all you need to do is keep altering the value of Staff reading to check the level.
Story:
I was working on a construction site in the Raigad district and used an auto-level to transfer the levels of the foundation work. We had to cast a number of footings for a production unit and a warehouse. It was a bit tedious to carry a calculator, save the TBM RLs in a variable and run a quick computation in the sunny and bad uncertain monsoon weather.
As a solution, I was thinking of creating a spreadsheet that I could use on my phone, and to a certain extent, it worked good but had a few limitations like a bad UI and the need for me to zoom in and zoom out to fill in values.
I found an app on the Google Playstore that allowed me to code the same calculations with minimal coding. It was based on scratch so the coding was taken care of in the background but I had to provide the logic. With a few trial and errors, I was able to complete the app and get it working for myself and believe me, it made my work so easy that I used to start it once during the day, set up my instrument, and for the entire day it was working great. It was very good when I had to move my instrument due to some work, resetting and getting it working again was very simple.
Now that the app was working great for me, I decided to share it with other, first the site engineer, supervisors, and then even the laborers. I was glad to see that we were able to get the complicated task of transferring levels using an auto-level by labor who had never used that instrument before. I had to train him on how to take the readings and with some practice, he was good to go. I had installed that app on his MI phone, not sure why but MI phones were cheap and quite popular amongst construction workers during that time.
Finally, I had to leave the site to grab an opportunity I'd been eyeing for quite a long time. But, still, the app is in use by a number of people and a few have motivated me to put it on the play store. Sure, I'll be looking forward to putting it there as well. At the moment the app is still buggy, it kinds of crashes when there's no input in the TBM field and you try to run the calculations but overall it gets the work done so it isn't a show stopper.
Check out my site tour video on Youtube
If you're a programmer and would like to collaborate on this, please do get in touch with me.
Thanks for reading, please comment and share your views.
Shadaab
Engineering the Digital Civilization