{"id":24493,"date":"2026-02-01T11:11:50","date_gmt":"2026-02-01T11:11:50","guid":{"rendered":"http:\/\/141.23.68.248\/wp\/?page_id=24493"},"modified":"2026-02-08T16:13:05","modified_gmt":"2026-02-08T16:13:05","slug":"4-life-cycle-analysis","status":"publish","type":"page","link":"http:\/\/141.23.68.248\/wp\/?page_id=24493","title":{"rendered":"4. Life-Cycle Analysis"},"content":{"rendered":"\n

In the context of large-scale infrastructure, LCA is an indispensable tool. Because these assets are designed for extreme longevity -in this case, a 120-year lifespan- decisions made during the initial design and early maintenance phases have massive compounding effects. By applying LCA, we can move beyond “first-cost” thinking and understand the true environmental and economic price of an asset over a century of service. This allows us to optimise maintenance intervals, select resilient materials, and ultimately reduce the long-term footprint of our built environment.<\/p>\n\n\n\n

<\/div>\n\n\n\n

Goal<\/h2>\n\n\n\n
<\/div>\n\n\n\n

The primary goal of this Life Cycle Assessment (LCA) is to evaluate the long-term sustainability and economic viability of the optimised maintenance strategy defined in our Maintenance Planning<\/a> phase. Embodied energy reflects the total energy demand of material production and serves as a proxy for resource intensity and long-term sustainability [1]<\/strong>.<\/p>\n\n\n\n

CO\u2082 emissions reflect the primary indicator of climate impact, aligning with international decarbonization objectives such as the UK\u2019s Decarbonising Transport initiative [14]<\/strong><\/p>\n\n\n\n

NO\u2093 emissions were included as a critical indicator for local air quality and human health, regulated under stringent UK and EU standards.<\/p>\n\n\n\n

Cost was incorporated because publicly funded bodies with limited budgets manage most rail networks. As a result, financial constraints are inseparable from environmental and operational considerations in maintenance planning [13]<\/strong><\/p>\n\n\n\n

<\/div>\n\n\n\n

Scope<\/h2>\n\n\n\n
<\/div>\n\n\n\n

The analysis is conducted over a 120-year lifespan, capturing the compounding environmental and economic effects of recurring maintenance cycles on the train station system as defined in the integration context<\/a> section.<\/p>\n\n\n\n

<\/div>\n\n\n\n

Boundary<\/h2>\n\n\n\n
<\/div>\n\n\n\n
\"\"<\/a>
Figure 1 – Boundary Diagram
<\/figcaption><\/figure>\n\n\n\n
<\/div>\n\n\n\n

This study adopts a cradle-to-gate boundary, incorporating maintenance impacts derived from R calculations.<\/p>\n\n\n\n

Figure 1, boundary diagram This boundary was selected to maintain a high level of data integrity for this specific challenge. Transportation, construction logistics, operational energy, and end-of-life processes are highly variable and strongly influenced by external factors such as user behaviour, supply chains, and future policy conditions. To avoid introducing speculative assumptions, these stages were excluded, ensuring that the results reflect documented industrial manufacturing data rather than uncertain logistical estimates. Focusing on material production and maintenance-related impacts enables the analysis to isolate the direct consequences of maintenance scheduling decisions. This controlled system boundary allows consistent comparison between alternative strategies and highlights the influence of maintenance planning on long-term environmental and economic performance.<\/p>\n\n\n\n

<\/div>\n\n\n\n

Maintenance LCI Table<\/h2>\n\n\n\n
<\/div>\n\n\n\n

Table 1 outlines the life cycle inventory for materials used across our maintenance events. Because our infrastructure assets vary in type, material quantities are scaled to the specific functional unit of each intervention (detailed in the “Units” column).<\/p>\n\n\n\n

Embodied energy, emissions (CO2 and NOx), and costs are calculated as impact factors per kilogram (kg). This standardised approach allows for direct material comparisons. Zinc-vinyl coating is evaluated per m\u00b2 to reflect it\u2019s functional unit.<\/p>\n\n\n\n

All costs are ex-works, representing factory-gate prices in Germany. This excludes shipping, handling, and installation.<\/p>\n\n\n\n

<\/div>\n\n\n\n
Material<\/th>Quantity<\/th>Unit<\/th>Energy (MJ\/kg)<\/th>CO2<\/sub> (kg\/kg)<\/th>NOx<\/sub> (kg\/kg)<\/th>Cost (\u20ac\/kg)<\/th><\/tr><\/thead>
Reinforced concrete<\/td>506.25 [2]<\/td>kg\/m\u00b2<\/td>1.095 [2]<\/td>0.187 [2]<\/td>0.0298 [6]<\/td>0.258 [7]<\/td><\/tr>
EPS insulation<\/td>20 [3]<\/td>kg\/m\u00b2<\/td>89 [3]<\/td>2.8 [3]<\/td>0.009 [6]<\/td>4.09 [8]<\/td><\/tr>
TiO2<\/sub> coating<\/td>0.3 [4]<\/td>kg\/m\u00b2<\/td>93 [4]<\/td>7.5 [4]<\/td>0.001 [6]<\/td>47.3 [4\/7]<\/td><\/tr>
Sealant<\/td>0.08 [5]<\/td>kg\/m<\/td>85 [5]<\/td>4.2 [5]<\/td>0.005 [6]<\/td>12.9 [8]<\/td><\/tr>
Aluminium<\/td>42.3 [20\/22]<\/td>kg\/m\u00b2<\/td>3.3 [20\/22]<\/td>0.11 [20\/22]<\/td>0.00026 [20\/22]<\/td>3 [25]<\/td><\/tr>
IGU \/ Float Glass<\/td>30 [20\/23]<\/td>kg\/m\u00b2<\/td>7.5 [20\/23]<\/td>1.45 [20\/23]<\/td>0.0003 [20\/23]<\/td>2.1 [26]<\/td><\/tr>
EPDM Gasket<\/td>0.3 [20]<\/td>kg\/m\u00b2<\/td>0.2 [20]<\/td>0.08 [20]<\/td>0.0004 [20]<\/td>6.2 [27]<\/td><\/tr>
Cleaning agent<\/td>0.05 [20\/21]<\/td>kg\/m\u00b2<\/td>5 [20\/21]<\/td>1.8 [20\/21]<\/td>0.004 [20\/21]<\/td>2.5 [26]<\/td><\/tr>
High-Strength Repair Mortar<\/td>5.87<\/td>kg\/m\u00b2<\/td>99.5 [1]<\/td>4.65 [15\/16]<\/td>0.0045 [Ivy M.]<\/td>16 [1]<\/td><\/tr>
Polyurethane (PU) Sealant<\/td>0.12<\/td>kg\/m<\/td>85 [17]<\/td>3.2 [17]<\/td>0.0025 [Ivy M.]<\/td>8 [17]<\/td><\/tr>
Anti-Carbonation<\/td>3<\/td>kg\/pillar<\/td>60 [16]<\/td>2.5 [16]<\/td>0.0021 [Ivy M.]<\/td>10 [16]<\/td><\/tr>
High-Strength Cement Grout<\/td>30.7<\/td>kg\/slab<\/td>5 [1]<\/td>0.9 [18]<\/td>0.0016 [Ivy M.]<\/td>1.2 [1]<\/td><\/tr>
Steel S355<\/td>64380<\/td>kg\/bridge<\/td>30 [28]<\/td>2.01 [28]<\/td>0.003 [Ivy M.]<\/td>1 [29]<\/td><\/tr>
Zinc-vinyl coating*<\/td>450<\/td>m\u00b2\/bridge<\/td>18.9* [30]<\/td>1.6* [30]<\/td>0.0037* [30]<\/td>24.7* [31]<\/td><\/tr>
Concrete<\/td>260<\/td>kg\/sleeper<\/td>1.1 [33]<\/td>0.13 [32]<\/td>0.0003 [6]<\/td>0.258 [7]<\/td><\/tr>
Steel<\/td>60.21<\/td>kg\/m<\/td>33.5 [34]<\/td>2.5 [35]<\/td>0.00066 [28]<\/td>0.66 [37]<\/td><\/tr>
Timber sleeper \u2013 Oak<\/td>750<\/td>kg\/m\u00b3<\/td>10.4 [1]<\/td>0.87 [1]<\/td>0.00015 [6]<\/td>1.85 [9]<\/td><\/tr>
Timber \u2013 Wood preservative<\/td>60<\/td>kg\/m\u00b3<\/td>51 [1]<\/td>0.43 [1]<\/td>0.0045 [6]<\/td>2.28 [11]<\/td><\/tr>
Polypropylene geotextile<\/td>0.45<\/td>kg\/m\u00b2<\/td>95.4 [1]<\/td>4.98 [1]<\/td>0.0038 [6]<\/td>1.033 [12]<\/td><\/tr><\/tbody><\/table>
Table 1 – Life cycle inventory per material
*Note: For Zinc-vinyl, emissions are measured per m\u00b2, not per kg.<\/em>
<\/figcaption><\/figure>\n\n\n\n
<\/div>\n\n\n\n

Maintenance Inventory and Material Quantities<\/h2>\n\n\n\n
<\/div>\n\n\n\n

The material quantities for each maintenance event were derived from a combination of literature review and structural estimations.<\/p>\n\n\n\n