PTV Visum is described as 'is used to model transport networks and travel demand, to analyse expected traffic flows, to plan public transport services and to develop advanced transport strategies and solutions'. There are more than 10 alternatives to PTV Visum for Windows, Linux, Mac and Docker. The best alternative is Anylogic. It's not free, so if you're looking for a free alternative, you could try MATSim or Simulation of Urban MObility (SUMO). Other great apps like PTV Visum are TransCAD (Paid), TSIS-CORSIM (Paid), HCS (Paid) and TransModeler (Paid).
AnyLogic is a cross-platform multimethod simulation modeling tool developed by The AnyLogic Company (former XJ Technologies). It supports agent-based, discrete event, and system dynamics simulation methodologies.
"Simulation of Urban MObility" (SUMO) is an open source, highly portable, microscopic and continuous road traffic simulation package designed to handle large road networks. SUMO is licensed under the Eclipse Public License V2.
TSIS is an integrated development environment that enables users to conduct traffic operations analysis. Built using a component architecture, TSIS is a toolbox that contains tools that allow the user to define and manage traffic analysis projects.
This release of the Highway Capacity Software (HCS7) includes updated modules to implement the Highway Capacity Manual 6th Edition (HCM6) procedures for Signalized Intersections, Urban Streets, Alternative Intersections, Roundabouts, Freeway Facilities, Basic Freeway Segments...