VISION tool
What is VISION tool?
The VISION tool is a dynamic simulation model designed to illustrate the life cycle of concrete and soil within the construction industry. It integrates key environmental components by calculating CO₂ emissions associated with cement production, aggregate use, transportation, and waste processing—offering a comprehensive view of the sector’s environmental impact. Through scenario-based modeling, VISION enables the simulation of circular economy strategies, allowing for comparative analysis of their effectiveness in promoting sustainable construction practices.
Tutorial
Definition of Variables:
- Concrete Recycle %: Fraction of concrete from demolished houses used in new construction.
- Soil Reuse %: Fraction of soil from demolished sites reused in new construction.
- Max RCA Permitted: Maximum share of recycled concrete allowed in new buildings.
- Houses Built/Demolished Per Year: Number of houses built or demolished annually.
- Number of Years: Period for scenario comparison.
- Materials / Metrics: Which results to display on the graphs.
Understanding the Graph Values:
- Total CO2: Total CO₂ emissions in kg.
- Recycled Concrete: Total recycled concrete used in tonnes.
- Virgin Aggregate: Aggregate extracted from natural sources in tonnes.
- Reused Soil / Virgin Soil: Soil reused or newly used in tonnes.
- Sand and Gravel Saved: Quantity of sand and gravel saved by using recycled concrete in tonnes.
Simulation Inputs: Choosing Simulation Variables
- Concrete Recycle %: Enter a value between 0 and 1 (0 = no recycled concrete, 1 = 100% of demolished concrete reused). Higher values reduce the need for new concrete, lowering CO₂ emissions from production and transport.
- Soil Reuse %: Enter a value between 0 and 1. More reused soil reduces the extraction of virgin soil, lowering transport emissions and environmental impacts.
- Max RCA Permitted: Enter a value between 0 and 1. This limits the recycled concrete actually used. A low limit forces the use of more virgin concrete.
- Houses Built/Demolished Per Year: Enter positive integers. More houses built increase material demand and emissions; more demolished houses increase potential recycled concrete and soil. Avoid negative or unrealistic values like letters.
- Number of Years: Enter an integer ≥ 1. Extends calculations over multiple years to show cumulative effects. Avoid zero or negative numbers.
Simulation Results
- Summary of chosen parameters: Houses built/demolished per year and number of years.
- Results table: Total CO₂ emissions (kg), recycled concrete used (t), virgin aggregate used (t), reused soil and virgin soil (t), sand and gravel saved (t).
- CO₂ Breakdown Chart: Shows emissions from cement production, transport, waste processing, and virgin soil, helping identify major emission sources (kg).
Scenario Comparison Results
- Define Scenario A and Scenario B with different values for concrete recycling, soil reuse, and RCA limits.
- Select which values to display: CO₂ total, recycled concrete, reused soil, sand and gravel saved, etc.
- View line graphs over multiple years for each metric and scenario. The “best” scenario is highlighted for each metric, making comparisons clear.
- Compare cumulative final values between scenarios for a single year or the entire period.
- You need to click on a scenario if you want to see only one scenario (above the graph).