How to Set Pipe Invert Level Based on Gradient

For utility modules, you might have situations where you want to maintain a certain gradient for your pipe to cater for the site constraints or the design requirements. Rather than manually determining the invert levels of each pipe for a fixed gradient, MiTS allows users to input the desired gradient and it will automatically propose the suitable start and end IL based on settings.

Sewerage and Drainage Module #

Change Gradient Setting at Spread Input #

To set the gradient, you may change at the spread input under the Gradient column, where you first need to change the Iterate setting from Yes to No. Iterate =  Yes setting will allow the software to compute suitable gradient based on the overall design.

So to fix the gradient, you need to change Iterate = No setting to allow for user defined gradient. Then you will be able to insert the gradient value accordingly for each pipe.

Change Gradient Setting at RHS Properties Tab #

If you plan for all your pipes to have the same gradient, you are also able to directly set the gradient of all newly created pipes at the RHS properties setting other than changing the gradient at the spread input. Please note that this settings here will only be applied to the pipes created after the settings are changed. For existing pipes, please refer above.

Before inputting any nodes or pipes, users need to change the ‘End Invert Level Setting’ from ‘Default Setting’ to ‘Calculated by Gradient’. Then, you will be able to input the gradient value. Please note that it is important to also change the ‘Iterate Gradient’ setting from ‘Yes’ to ‘No’. If not, the software will propose the suitable gradient instead of following the gradient that you input when you analyse your design.

Limitations #

The gradient input (user defined) needs to be in the allowable range of 50.00 to 200.00 for sewer pipe and for drain, it would depend on the drain types used. Otherwise, you may need to change the minimum or maximum gradient setting if it is allowable to do so in your design.

So make sure that your input gradient is within the range, else you will get a verification error of ‘Gradient is out of range’. Another limitation is regarding the iteration setting on the IL and gradient.

While having the gradient setting to be fixed (Iterate = No), users cannot have both start and end IL to also set to Iterate = No. If the user did not allow for the software to have freedom to propose either on the IL or gradient, you will get an error and analysis will fail due to software not able to propose suitable values.

Below (Image 1.3.3 & Image 1.3.4) are the possible errors when we set both IL and the gradient to be Iterate = No with the gradient set does not reflect the calculated gradient from IL.

Make sure to leave an opening for the software to propose either the start IL or the end IL once you decide to fix the gradient.

Water Reticulation Module #

As for the water reticulation module, the setting is quite different from the drainage and sewerage module. The gradient column at the spread input only serves to show the gradient value. Users are not able to edit the gradient directly at the spread input.

However, you are allowed to directly set the gradient of all newly created pipes at the RHS properties setting. Please note that this settings here will only be applied to the pipes created after the settings are changed.

Before inputting any nodes or pipes, users need to change the ‘Specify Gradient’ from ‘Default Setting’ to ‘Calculated by Gradient’.  Then, you will be able to input the gradient value.

It is worth to note that for the water reticulation module, once you make any changes to the ground level or the start and end invert level, the gradient will then automatically be calculated according to the new IL and no longer follow the inputted gradient.