BargeSafe – Trim and Stability Calculator for Pontoon Barges

Description

****The price indicated is per-vessel per-year. There’s no automatic payment, and to continue usage after a year, the user needs to repurchase the app****

What does this Excel-based App do?

This App can be used to calculate Trim, Hydrostatics, and Ship Stability for an unmanned Pontoon Barge for any loading condition

How to use this App

After you purchase, input the following to prepare the database of the vessel:
1. Principal Particulars of the Vessel
2. Hydrostatics of the Vessel (zero trim and zero heel)
3. Cross Curve Data of the Vessel
4. Downflooding points location
5. Tanks data
6. Existing Stability booklet of the vessel (Generally the above data is available in the Stability Booklet)

Once the above is done, the user can create a new loading condition by giving it a unique name. The user has to input the Tank status, Fixed Weights, and Deck Cargo for the loading condition
Once all inputs for a loading condition are provided by the user, the user can Solve the Loading condition. This will give the GZ curve, Trim, and Heel status
Once a loading condition is solved and floating hydrostatics obtained, the stability can be evaluated as per IMO A749(18) Sec 4.7 which applies to Pontoon Barges

Assumptions/Limitations
The origin of the vertical axis is at the baseline of the vessel
Vessel is assumed to be symmetrical Port and Stbd
Only hydrostatics for zero heel and zero trim are utilised in calculations, so this spreadsheet is to be used only for low trim conditions (upto 5 deg)
The effect of free surface in tanks is calculated by considering the effect of free surface as a rise in the VCG of the vessel
While this may not represent the actual CG shift in tanks, it is a conservative approach in evaluation of the Righting Lever GZ
If detailed tank characteristics are not available, then the app calculates the FSM considering the tank as rectangular. While this may not be accurate for tanks which are not rectangular in shape, this gives conservative results

References
1. Principles of Naval Architecture, Vol 1, Edward V. Lewis
2. IMO Res A749(18), Code of Intact Stability for all types of Ships – Section 4.7 (Barges)