Motivation: #

In MiTS road design, cut-and-fill computations are determined by comparing the finished road level to the existing ground level.

However, this is not the case for an overpass- an elevated road structure that is supported by piers or abutments, typically designed to facilitate traffic movements. If the traditional cut-and-fill concept is applied for an overpass, the software will fill the entire void beneath the structure– this leads to inaccurate volumes as the non-existent fill is included in your computation.

So, how can we ensure this non-existent fill volume is not considered for a more accurate road cut and fill volumes in MiTS?

Exclude Sections feature in MiTS 3 Road & Highway Module #

It is possible to exclude the overpass in cut and fill computation with our latest feature, Exclude Sections (Per road basis), available in the Horizontal Alignment design.

This feature allows users to exclude a specific section of the chainages across your road stretch, and the exclusion will be reflected in the Road End Area Report.

Steps to be applied: #

Sample project file here

Step 1: Setting up your existing ground level #

The existing ground level is required to ensure the cut and fill can be done for your at-grade roads.

In the project file,

Input > Survey Points & Soil Info section > Import Manage

For detailed steps, users may refer to our User Manual, Steps to Import Survey Data.

Step 2: Define the road and its centerline #

• In the Road & Highway Module, define the road under Project View on the left grid of the program.

• Model the centerline (horizontal alignment) of the road by going to

Input tab of Roa & Highway Module > Horizontal > Line > Click anywhere to activate your cursor > Place the IPs, which will be connected to represent the centerline

• Set a proper Design Standard and Design Speed for your road.

• Repeat the steps above for your overpass road.

Step 3: Design the Vertical Alignments of the roads #

To design the road levels, go to

• Vertical > Line > Click to update the cursor and place the start point- Do note the start point should be equivalent to the start chainage.

• Continue to create the vertical alignment until the end chainage- Do note that the end point should be equivalent to the end chainage displayed.

• To add more points for the vertical elevation of the road, go to

Vertical > Point > Click on ‘+’ icon under Spread Input > Enter the chainage offset and the elevation

• Repeat the steps for the overpass road. However, for the overpass, you will need to ensure the elevation passes the height clearance for the vehicles accordingly. As an example,

Determine the chainage where the overpass will start and end. You may

select the overpass road under Project View > click Cross Section > click at the start and end of the overpass > the software will detect the chainages automatically

• For the elevation, let’s say the clearance is 5.4m; Add this value to the elevation of the at-grade road beneath the overpass.

Possible error faced #

Once the vertical IPs and levels are input, you may find that the vertical curves overlap, as in the image below.

These overlaps stemmed from the K and Vertical Curves Length (VCL) applied to the vertical lines- These values are available under

Vertical > Curves > Spread Input

In this overpass design, it may not be possible to apply the standard values. Hence, it is recommended to adjust the K and VCL values accordingly.

Step 4: Excluding the overpass chainages from the cut and fill computation #

One of the pros of designing with the MiTS Road & Highway Module is that users do not have to generate any platforms or slopes to obtain the cut and fill volume.

Excluding the chainages: #

• Select the overpass road from the Project View > Horizontal > Line > Right-Hand Side Properties Tab > Click on the Edit button

• Under the Exclude Section dialog, input the Start chainage and End chainage (should be the start and end of the overpass, similar to the vertical alignment design) and click OK

Generate the End Area Cut-and-Fill Report #

• Ensure there is no verification error related to your road design. For warnings, you may ignore them if needed.

• Click on Road Output > The End Area Report will be launched > Go to the Detail Calculation for the overpass road > the cut and fill computed will skip the chainages excluded above.

Tutorial Video: #

Users may refer to the video below for visual guides.