Bridge Construction - Field Preparation

Challenge

The question to answer was how to model, analyze, and sustain the workflow and productivity of a construction system under dynamic constraints and hierarchical decision-making entities. The focus was analyzing the impact of simulation parameters on system effectiveness, taking into account real-time situations and giving insight to the project management team on the best control approach.

The objectives were to:

• Generate and optimize a construction schedule
• Revise and re-optimize the schedule during disruptions
• Offer a decision-making platform for the project team

The problem required consideration of the interactions and workflows of several working members (project manager, construction manager, operators, etc.), external influences (rain, road accidents), management techniques, and machine optimization.

Solution

A multi-method simulation model was developed in AnyLogic:

• Agent-Based modeling captured the interactions between individuals for project initiation — meetings, research, proposal construction, finding internal or external resources, etc.
• Discrete-Events simulated the field activities to clean, dig, fill, and prepare the terrain for bridge construction
• System Dynamics simulated the external influence of rain and bad weather on the field

The project also required construction of a full business process model, with training and support.

Outcome

Under normal conditions, 2 bulldozers and 2 excavators per area were defined. But what if the manager says one is enough? A Monte Carlo experiment was developed to understand the risk of not meeting the deadline under different machine configurations. Weather was the most critical influence affecting project outcomes.

Key Findings

• With only 1 team of machines per area: ~680 days to finish
• With 17 teams of 2 bulldozers and 2 excavators each: only 300 days
• Optimal target of finishing within 500 days led to this configuration:
• Number of bulldozers: 2
• Number of excavators: 2
• Areas per cluster: 11 (equivalent to 3 teams)

The simulation serves as a tool usable in different terrains with different external influences as a project management tool to define the correct use of resources and work strategy.

Project Features

• Industry: Construction
• Model: Discrete Events, Agent-Based, System Dynamics
• Duration: 1 year