Innovation · AECOM India Pvt Ltd
Souvik Biswas is a Structural Engineer at AECOM India Pvt Ltd. Before joining AECOM, Souvik Biswas did doctoral research at IIT (ISM) Dhanbad on how highway bridges respond to seismic, blast and fire loading. Today much of the bridge modelling runs through a Python script. Here is why Souvik Biswas automated it, and where the time saved goes.
In Souvik Biswas's own words.
"A finite element model can give you a very precise result
and still be wrong if the assumptions behind it are wrong."
I have always felt that it is important to understand what is happening behind the numbers, question results that do not seem right, and check whether the model actually makes sense from an engineering point of view. Whether it is modelling construction stages, checking load assumptions or validating a complex model, I try not to let the software make the judgement for me. That is something I want to keep carrying with me as I grow as an engineer.
Checking the model against the shake table
As a doctoral researcher at IIT (ISM) Dhanbad, I investigated the structural response of highway bridges under seismic, blast and fire loading. A major part of the research involved system-level testing of 1:8 scale reinforced concrete slab culverts on a shake-table facility, along with developing finite element models and validating them against the experimental results. This experience taught me to look beyond numerical results and critically assess whether a model actually represents real structural behaviour.
Automating the repetitive part
I found that creating complex bridge geometry and applying loads manually was repetitive and also created opportunities for small input errors. Instead of continuing with the usual workflow, I started using Python with the MIDAS Civil NX REST API to automate parts of the modelling process. I first focused on automating geometry and node generation, then extended the approach to loading and model verification.
The result was a more consistent workflow, less repetitive manual work and greater confidence in the models being created. More importantly, it showed me that automation does not have to replace engineering judgement. It can remove repetitive work and allow more time to be spent checking whether the model and its results actually make engineering sense.
From one span to the whole structure
On a Metro project, I developed and analysed the model for a 35m curved steel composite span, including metro train live loads and the centrifugal forces arising from the curvature. It gave me practical experience in translating complex geometry and loading into a reliable structural model.
I also developed the MIDAS Civil NX structural model of a 430 m long steel composite foot over bridge, including the steel superstructure, composite deck, eccentric steel piers and the pile foundation with pile caps. The modelling had to represent the overall behaviour and the load transfer from the superstructure through the eccentric piers into the piles and pile caps. Working on the complete system gave me a better understanding of how modelling decisions in one part of a structure can influence the behaviour and design of the structure as a whole.
Q. When did MIDAS start to look like something more than an analysis program?
When I started using the MIDAS Civil NX API with Python to automate parts of the bridge modelling process. Until then, I had mostly thought of MIDAS as a tool I used to build and analyse models. Working with the API changed that perspective. I realised I could build my own workflow around the software, automate repetitive tasks and put checks in place to make the modelling process more consistent.
I no longer see it only as an analysis program, but as a platform that I can adapt to the way I work and use to solve engineering problems more efficiently.
Souvik Biswas automated the repetitive parts of bridge modelling and put the time saved back into checking. Souvik Biswas tells us that automation does not have to replace engineering judgement, since a modelling decision in one part of a structure can change how the whole structure behaves. That is why Souvik Biswas tries not to let the software make the judgement.