Once upon a time I did a project at university on traffic simulation. In case you’re interested, here is some information about it.
I used NetLogo, an agent-based modelling (ABM) environment, to design and implement a simple working traffic simulation model.
This is quite a cool piece of software and if you’re interested in multi-agent modelling I recommend you check it out. There’s loads of online models you can run in your browser.
You can read more about the project here.