# Simulation

> We create digital simulations based on project requirements: 4D construction sequences, 5D cost analysis and virtual control rooms. They help choose phases and methods before they turn into costs on site.

A simulation links the BIM model to the construction schedule (4D) and to costs (5D). The result is a virtual build of the asset, phase by phase, on which the team checks sequences, time clashes, site areas and the cost impact of each choice.

BIMON uses simulations from tender to site. On the Intermodal Territorial Interconnection Center (CITT) of the new Mexico City Airport, for Astaldi, time and cost simulations made it possible to optimize the solutions proposed in the bid. On the Naples-Bari high-speed rail line, for Pizzarotti, the model was used for 4D and 5D simulations of the construction phases and for quantity estimates. On the new Skurusund bridge in Sweden a 4D model showed the construction sequence and gave constructability feedback for program revisions.

During construction the simulation becomes a site tool. On the WTE trigeneration plant in Trieste, for Hera Group, simulations of the phases and installation methods of the components helped resolve clashes before they appeared on site and keep to the schedule. At Fiumicino and at Naples-Afragola station the construction model made it possible to anticipate problems that would otherwise have surfaced during the works.

Virtual control rooms bring this content into a shared environment where designers, contractor and client read the same model and the same schedule. You need them when the asset is complex, when the site sits next to infrastructure in operation, or when the tender rewards improvements on time and cost.

## Deliverables

- Virtual Control Rooms
- 4D time simulations
- 5D cost simulations

## Process

1. **Simulation goals** — With the client we define the questions the simulation must answer: phasing, construction methods, site areas, comparison between alternatives.
2. **Model and schedule** — We organize the BIM model by WBS and link it to the schedule and, for 5D, to quantities and unit prices.
3. **Simulation and analysis** — We run the simulation, identify time clashes and critical points, and propose sequence alternatives.
4. **Sharing** — We deliver videos, reports and, where required, a virtual control room to use in coordination meetings.

## FAQ

**What are 4D and 5D simulations?**

4D links the BIM model objects to the construction schedule and shows how the asset is built over time. 5D adds quantities and costs, so every phase also has an economic value. Together they let you compare construction alternatives before works start.

**Are simulations useful at tender stage?**

Yes. On the new Mexico City Airport and the Naples-Bari line BIMON used the model and simulations at tender stage, to verify quantities and optimize the proposed improvements on time and cost. A bid backed by a simulation is easier to demonstrate to the contracting authority.

**What is a virtual control room?**

It is a shared digital environment where the model, the schedule and project data can be consulted from one place. Designers, contractor and client can follow the simulated phases and make decisions on the same information base.