Evaluating Carbon Emissions during Slurry Shield Tunneling for Sustainable Management Utilizing a Hybrid Life-Cycle Assessment Approach
Abstract
:1. Introduction
- Flexible: It can be used as two different methods to estimate the GHG emissions during different phases of a tunnel. Instead of one single method, we opt for one method or the other or both, depending on site conditions, data category, local market, etc. It will be possible to adjust the carbon emissions factors according to the country or region specifics.
- Effective and time-saving: The task of calculating the GHG emissions, especially by P-LCA, is data-intensive and time-consuming. With the I-O LCA method based on the monetary value and conversion factor to CO2, we can make a rapid calculation of GHG emissions. The P-LCA method is not efficient enough to achieve the calculation target under severe missing data circumstances. This hybrid approach may be effective by completing missing data in the life-cycle inventory.
- Easy to implement: No special skills are required for its practice. The simplicities of the proposed hybrid method are based on the following: (a) the budget quota and energy consumption of tunnel construction; (b) the use of the conversion factor method to convert the amount of energy and materials consumed into GHG emissions; (c) focus not on the whole life cycle but on the construction phase of a tunnel; (d) only account for the CO2 emissions and not for other gas emissions.
- Provide a holistic view of GHG emissions: This hybrid approach could provide a rounded analysis of the emissions associated with materials production, materials materialization, materials transportation and off-road machinery. It can not only address those emissions arising from auxiliary materials (grease, bentonite, PVC pipe and rubber material) but also provide a method to estimate the emissions during the upstream fuel when carbon emissions factors do not consider indirect emissions.
2. Research Background
2.1. Carbon Emissions during the Tunnel Construction Process
- Materials production: The main materials considered are cement, steel bars, sand and gravel aggregates, etc., and auxiliary materials, including PVC pipe, adhesive, steel molds and wooden molds.
- Materials materialization: This mainly includes the production, maintenance and installation of prefabricated components and the work of casting.
- Materials transportation: It involves raw materials and prefabricated components transportation around the construction site.
- Off-road machinery: It mainly refers to construction machinery needed to perform tasks during the course of tunneling, including shield tunneling, slurry treatment and recycle, casting, lining and auxiliary services including ventilation and light during construction.
2.2. Life-Cycle Assessment Background
2.3. P-LCA Model for GHG Emissions during Tunnel Construction
2.3.1. GHG Emissions Released from Materials Used
2.3.2. GHG Emissions Produced during Materials Transportation
2.3.3. GHG Emissions Emitted by Off-Road Machinery during the Excavation
2.4. I-O-LCA Model for GHG Emissions during Tunnel Construction
2.4.1. GHG Emissions Released from Materials Used
2.4.2. GHG Emissions Produced during Materials Transportation
2.4.3. GHG Emissions Emitted by Off-Road Machinery during the Excavation
3. Hybrid Model Development
3.1. Method Slection Discussion
3.1.1. Materials Production
3.1.2. Material Materialization
3.1.3. Materials Transportation
3.1.4. Off-Road Machinery
4. Case Study
4.1. Inventory Data
4.2. Results and Analysis
4.3. Discussion
5. Conclusions
- (1)
- The GHG emissions of the tunnels with 41 rings are 2895.07 × 103 t CO2 eq, with the GHG emissions of each ring ranging from 69.68 × 103 t CO2 eq to 71.93 × 103 t CO2 eq.
- (2)
- Materials accounting for 93.88% of total emissions have a leading role in carbon reductions. Among these materials, segments contributed most of the GHG emissions associated with the materials. Altering the reinforcement ratio of segments can help meet the materials GHG emission reduction targets on the premise of structural stability and durability.
- (3)
- During the material materialization stage, by switching to renewable energy sources instead of diesel when producing steam for segment maintenance, the goal of emission reductions during the stage can be achieved.
- (4)
- GHG emissions from materials transportation are subject to the site’s location. Avoiding separating the materials prefabrication site and tunnel construction site may lead to great progress in reducing GHG emissions from transportation.
- (5)
- GHG emissions during the tunneling stage have a significant bearing on the efficiency of tunnel construction, and they are negatively correlated. The results suggest that at least three rings per day should be maintained so as to reduce energy waste.
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
Appendix A
Material/Fuel | Unit | Emission Factors |
---|---|---|
C40 concrete [23] | kg/m3 | 288.9 |
C60 concrete [23,26] | kg/m3 | 222.3 |
Bolt [23,26] | kg/kg | 2.526 |
Grouting [23,26] | kg/kg | 71.4 |
Steel [26] | kg/kg | 2.364 |
Grease [27,28] | kg/104CNY | 3710 |
Bentonite [27,28] | kg/104CNY | 5420 |
PVC pipe [27,28] | kg/104CNY | 6232.2 |
Rubber [27,28] | kg/104CNY | 2210 |
Diesel [12] | kg/L | 2.655 |
Gasoline [12] | kg/t | 2.938 |
Electricity [12,24] | kg/KWh | 0.923 |
Materials | Specification | Unit | Quantity | Cost (CNY) |
---|---|---|---|---|
Segment | ||||
Concrete | m3 | 58.6 | 41,020 | |
Steel | kg | 10,507 | 48,122 | |
Mould | ||||
Concrete | m3 | 9.37 | 5809 | |
Steel | kg | 1748 | 8005 | |
Flue sheet | ||||
Concrete | m3 | 20.12 | 12,475 | |
Steel | kg | 2565 | 11,747 | |
Pavement | ||||
Concrete | m3 | 4.7 | 2915 | |
Steel | kg | 855 | 3916 | |
Bolt | Bolt | kg | 4.7 | 2915 |
Grouting | Grouting | m3 | 855 | 3916 |
Grease | Grease | kg | 200 | 23.50 |
Bentonite | Bentonite | t | 3.8 | 300 |
PVC pipe | PVC pipe | m | 4 | 260 |
Rubber material | Rubber material | ring | 1 | 1840 |
Process | Specification | Fuel | Energy Consumption per Ring |
---|---|---|---|
Prefabricated segment | |||
Steaming boiler | Diesel | 178 L | |
Steel processing plant | Electricity | 55.5 kWh | |
Electric air compressor | Electricity | 275.31 kWh | |
Vacuum chuck | Electricity | 246.05 kWh | |
Concrete mixing plant | Electricity | 180 kWh | |
Prefabricated mould | |||
Concrete mixing plant | Electricity | 72 kWh | |
Steel processing plant | Electricity | 154.6 kWh | |
Prefabricated flue sheet | |||
Concrete mixing plant | Electricity | 47.52 kWh | |
Steel processing plant | Electricity | 102.04 kWh | |
Flue sheet installation | |||
Installation plant | Electricity | 29.7 kWh |
Process | Specification | Fuel | Energy Consumption per Ring |
---|---|---|---|
Transportation vehicle | |||
Steyr truck | Gasoline | 331.20 L | |
Delivery truck | Gasoline | 6.08 L | |
Double-ended lorry | Gasoline | 0.81 L | |
Lorry | Gasoline | 5.79 L | |
Concrete mixing carrier | Diesel | 5.51 L |
Process | Specification | Fuel | Energy Consumption per Ring |
---|---|---|---|
Slurry disposal | |||
Disposing plant | Electricity | 1496.25 kWh | |
Roller screen | Electricity | 19.95 kWh | |
Spray | Electricity | 204.82 kWh | |
Water pump | Electricity | 129.01 kWh | |
Fluid pump | Electricity | 30 kWh | |
Shearing pump | Electricity | 55 kWh | |
Slurry delivery | |||
Sludge feed pump | Electricity | 47.65 kWh | |
Sludge discharge | Electricity | 47.65 kWh | |
Relay pump | Electricity | 47.65 kWh | |
Shied tunneling | |||
Cutter head driving | Electricity | 617.49 kWh | |
Cooling | Electricity | 25.38 kWh | |
Hydraulic assistance | Electricity | 135.34 kWh | |
Grouting | Electricity | 16.92 kWh | |
Electric air compressor | Electricity | 33.83 kWh | |
Ventilation | Electricity | 5.92 kWh | |
Ground support system | |||
Lighting | Electricity | 16.27 kWh | |
Ventilation | Electricity | 41.84 kWh | |
Electricity for working | Electricity | 41.80 kWh | |
Water discharge pump | Electricity | 25.57 kWh | |
Machine repair room | Electricity | 30.22 kWh | |
Crane | Electricity | 74.38 kWh |
No. | Segment | Mould | Flue Sheet | Pavement | Bolt | Grouting | Grease | Bentonite | PVC Pipe | Rubber Material | Total Emissions |
---|---|---|---|---|---|---|---|---|---|---|---|
1 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
2 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
3 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
4 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
5 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
6 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
7 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
8 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
9 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
10 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
11 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
12 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
13 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
14 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
15 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
16 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
17 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
18 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
19 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
20 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
21 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
22 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
23 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
24 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
25 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
26 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
27 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
28 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
29 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
30 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
31 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
32 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
33 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
34 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
35 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
36 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
37 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
38 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
39 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
40 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
41 | 37,865 | 6839 | 3379 | 11,876 | 1149 | 1761 | 1743 | 618 | 648 | 407 | 66,287 |
No. | Prefabricated Segment | Prefabricated Mould | Prefabricated Flue Sheet | Prefabricated Casting | Flue Sheet Installation | Total Emissions |
---|---|---|---|---|---|---|
1 | 1173 | 209 | 138 | 9 | 27 | 1557 |
2 | 1173 | 209 | 138 | 9 | 27 | 1557 |
3 | 1173 | 209 | 138 | 9 | 27 | 1557 |
4 | 1173 | 209 | 138 | 9 | 27 | 1557 |
5 | 1173 | 209 | 138 | 9 | 27 | 1557 |
6 | 1173 | 209 | 138 | 9 | 27 | 1557 |
7 | 1173 | 209 | 138 | 9 | 27 | 1557 |
8 | 1173 | 209 | 138 | 9 | 27 | 1557 |
9 | 1173 | 209 | 138 | 9 | 27 | 1557 |
10 | 1173 | 209 | 138 | 9 | 27 | 1557 |
11 | 1173 | 209 | 138 | 9 | 27 | 1557 |
12 | 1173 | 209 | 138 | 9 | 27 | 1557 |
13 | 1173 | 209 | 138 | 9 | 27 | 1557 |
14 | 1173 | 209 | 138 | 9 | 27 | 1557 |
15 | 1173 | 209 | 138 | 9 | 27 | 1557 |
16 | 1173 | 209 | 138 | 9 | 27 | 1557 |
17 | 1173 | 209 | 138 | 9 | 27 | 1557 |
18 | 1173 | 209 | 138 | 9 | 27 | 1557 |
19 | 1173 | 209 | 138 | 9 | 27 | 1557 |
20 | 1173 | 209 | 138 | 9 | 27 | 1557 |
21 | 1173 | 209 | 138 | 9 | 27 | 1557 |
22 | 1173 | 209 | 138 | 9 | 27 | 1557 |
23 | 1173 | 209 | 138 | 9 | 27 | 1557 |
24 | 1173 | 209 | 138 | 9 | 27 | 1557 |
25 | 1173 | 209 | 138 | 9 | 27 | 1557 |
26 | 1173 | 209 | 138 | 9 | 27 | 1557 |
27 | 1173 | 209 | 138 | 9 | 27 | 1557 |
28 | 1173 | 209 | 138 | 9 | 27 | 1557 |
29 | 1173 | 209 | 138 | 9 | 27 | 1557 |
30 | 1173 | 209 | 138 | 9 | 27 | 1557 |
31 | 1173 | 209 | 138 | 9 | 27 | 1557 |
32 | 1173 | 209 | 138 | 9 | 27 | 1557 |
33 | 1173 | 209 | 138 | 9 | 27 | 1557 |
34 | 1173 | 209 | 138 | 9 | 27 | 1557 |
35 | 1173 | 209 | 138 | 9 | 27 | 1557 |
36 | 1173 | 209 | 138 | 9 | 27 | 1557 |
37 | 1173 | 209 | 138 | 9 | 27 | 1557 |
38 | 1173 | 209 | 138 | 9 | 27 | 1557 |
39 | 1173 | 209 | 138 | 9 | 27 | 1557 |
40 | 1173 | 209 | 138 | 9 | 27 | 1557 |
41 | 1173 | 209 | 138 | 9 | 27 | 1557 |
No. | Segment Transfer | Segment | Mould | Flue Sheet | Grouting | Internal Materials | Total Emissions |
---|---|---|---|---|---|---|---|
1 | 973.08 | 1.66 | 0.22 | 0.73 | 1.36 | 8.96 | 986.00 |
2 | 973.08 | 2.47 | 0.33 | 1.10 | 2.02 | 8.96 | 987.96 |
3 | 973.08 | 3.27 | 0.43 | 1.47 | 2.67 | 8.96 | 989.89 |
4 | 973.08 | 4.09 | 0.54 | 1.83 | 3.34 | 8.96 | 991.84 |
5 | 973.08 | 4.90 | 0.65 | 2.20 | 4.00 | 8.96 | 993.80 |
6 | 973.08 | 5.71 | 0.76 | 2.57 | 4.67 | 8.96 | 995.75 |
7 | 973.08 | 6.52 | 0.87 | 2.93 | 5.33 | 8.96 | 997.69 |
8 | 973.08 | 7.33 | 0.98 | 3.30 | 6.00 | 8.96 | 999.65 |
9 | 973.08 | 8.14 | 1.09 | 3.67 | 6.65 | 8.96 | 1001.59 |
10 | 973.08 | 8.96 | 1.19 | 4.03 | 7.32 | 8.96 | 1003.54 |
11 | 973.08 | 9.76 | 1.30 | 4.40 | 7.98 | 8.96 | 1005.48 |
12 | 973.08 | 10.57 | 1.41 | 4.76 | 8.65 | 8.96 | 1007.44 |
13 | 973.08 | 11.39 | 1.52 | 5.13 | 9.31 | 8.96 | 1009.39 |
14 | 973.08 | 12.07 | 1.63 | 5.50 | 9.98 | 8.96 | 1011.21 |
15 | 973.08 | 13.00 | 1.74 | 5.86 | 10.64 | 8.96 | 1013.29 |
16 | 973.08 | 13.82 | 1.85 | 6.23 | 11.31 | 8.96 | 1015.24 |
17 | 973.08 | 14.63 | 1.95 | 6.60 | 11.97 | 8.96 | 1017.20 |
18 | 973.08 | 15.43 | 2.06 | 6.96 | 12.64 | 8.96 | 1019.14 |
19 | 973.08 | 16.25 | 2.17 | 7.33 | 13.30 | 8.96 | 1021.09 |
20 | 973.08 | 17.06 | 2.28 | 7.70 | 13.97 | 8.96 | 1023.05 |
21 | 973.08 | 17.88 | 2.39 | 8.06 | 14.63 | 8.96 | 1025.00 |
22 | 973.08 | 18.68 | 2.50 | 8.43 | 15.30 | 8.96 | 1026.94 |
23 | 973.08 | 19.49 | 2.61 | 8.80 | 15.96 | 8.96 | 1028.90 |
24 | 973.08 | 20.31 | 2.71 | 9.16 | 16.63 | 8.96 | 1030.85 |
25 | 973.08 | 21.12 | 2.82 | 9.53 | 17.29 | 8.96 | 1032.81 |
26 | 973.08 | 21.92 | 2.93 | 9.90 | 17.96 | 8.96 | 1034.75 |
27 | 973.08 | 22.74 | 3.04 | 10.26 | 18.62 | 8.96 | 1036.70 |
28 | 973.08 | 23.55 | 3.15 | 10.63 | 19.29 | 8.96 | 1038.66 |
29 | 973.08 | 24.37 | 3.26 | 11.00 | 19.95 | 8.96 | 1040.61 |
30 | 973.08 | 25.17 | 3.37 | 11.36 | 20.62 | 8.96 | 1042.55 |
31 | 973.08 | 25.98 | 3.48 | 11.73 | 21.28 | 8.96 | 1044.51 |
32 | 973.08 | 26.80 | 3.58 | 12.09 | 21.95 | 8.96 | 1046.46 |
33 | 973.08 | 27.60 | 3.69 | 12.46 | 22.61 | 8.96 | 1048.41 |
34 | 973.08 | 28.41 | 3.80 | 12.83 | 23.28 | 8.96 | 1050.36 |
35 | 973.08 | 29.23 | 3.91 | 13.19 | 23.95 | 8.96 | 1052.31 |
36 | 973.08 | 30.04 | 4.02 | 13.56 | 24.61 | 8.96 | 1054.27 |
37 | 973.08 | 30.84 | 4.13 | 13.93 | 25.28 | 8.96 | 1056.21 |
38 | 973.08 | 31.66 | 4.24 | 14.29 | 25.94 | 8.96 | 1058.17 |
39 | 973.08 | 32.47 | 4.34 | 14.66 | 26.61 | 8.96 | 1060.12 |
40 | 973.08 | 33.28 | 4.45 | 15.03 | 27.27 | 8.96 | 1062.07 |
41 | 973.08 | 34.06 | 4.56 | 15.39 | 27.94 | 8.96 | 1063.99 |
No. | Slurry Disposal | Slurry Delivery | Shield Tunneling | Ground Support System | Total Emissions |
---|---|---|---|---|---|
1 | 694.74 | 65.91 | 497.78 | 123.41 | 1381.84 |
2 | 694.74 | 65.91 | 497.78 | 123.41 | 1381.84 |
3 | 694.74 | 65.91 | 497.78 | 123.41 | 1381.84 |
4 | 694.74 | 65.91 | 497.78 | 123.41 | 1381.84 |
5 | 694.74 | 65.91 | 497.78 | 123.41 | 1381.84 |
6 | 694.74 | 65.91 | 497.78 | 123.41 | 1381.84 |
7 | 596.07 | 64.70 | 597.74 | 170.66 | 1429.17 |
8 | 596.07 | 64.70 | 597.74 | 170.66 | 1429.17 |
9 | 315.48 | 65.91 | 389.05 | 55.29 | 825.72 |
10 | 315.48 | 65.91 | 389.05 | 55.29 | 825.72 |
11 | 444.24 | 112.33 | 535.52 | 203.79 | 1295.88 |
12 | 414.71 | 69.04 | 551.77 | 113.99 | 1149.51 |
13 | 627.27 | 64.52 | 504.14 | 73.11 | 1269.03 |
14 | 531.56 | 62.49 | 484.76 | 59.07 | 1137.87 |
15 | 427.72 | 48.73 | 546.97 | 79.56 | 1102.99 |
16 | 427.72 | 48.73 | 546.97 | 79.56 | 1102.99 |
17 | 427.72 | 48.73 | 546.97 | 79.56 | 1102.99 |
18 | 705.36 | 74.95 | 941.83 | 304.41 | 2026.55 |
19 | 705.36 | 74.95 | 941.83 | 304.41 | 2026.55 |
20 | 705.36 | 74.95 | 941.83 | 304.41 | 2026.55 |
21 | 705.36 | 74.95 | 941.83 | 304.41 | 2026.55 |
22 | 522.60 | 78.17 | 891.07 | 199.37 | 1691.21 |
23 | 545.87 | 103.65 | 762.21 | 244.97 | 1656.69 |
24 | 594.50 | 172.32 | 632.63 | 283.55 | 1683.00 |
25 | 578.17 | 151.37 | 788.98 | 301.63 | 1820.16 |
26 | 578.17 | 151.37 | 788.98 | 301.63 | 1820.16 |
27 | 578.17 | 151.37 | 788.98 | 301.63 | 1820.16 |
28 | 578.17 | 151.37 | 788.98 | 301.63 | 1820.16 |
29 | 578.17 | 151.37 | 788.98 | 301.63 | 1820.16 |
30 | 668.07 | 196.23 | 993.42 | 285.95 | 2143.67 |
31 | 668.07 | 196.23 | 993.42 | 285.95 | 2143.67 |
32 | 668.07 | 196.23 | 993.42 | 285.95 | 2143.67 |
33 | 668.07 | 196.23 | 993.42 | 285.95 | 2143.67 |
34 | 668.07 | 196.23 | 993.42 | 285.95 | 2143.67 |
35 | 651.91 | 214.14 | 1102.70 | 227.79 | 2196.55 |
36 | 425.41 | 251.15 | 1212.64 | 322.59 | 2211.79 |
37 | 857.09 | 276.99 | 1409.89 | 471.75 | 3015.72 |
38 | 731.75 | 285.30 | 887.83 | 330.43 | 2235.31 |
39 | 704.24 | 278.75 | 840.21 | 324.35 | 2147.55 |
40 | 777.17 | 303.39 | 1411.73 | 92.21 | 2584.50 |
41 | 682.29 | 296.75 | 1502.92 | 262.59 | 2744.55 |
References
- IPCC 2022. Available online: https://www.ipcc.ch/sr15/ (accessed on 25 February 2024).
- Liu, Q.Q.; Wang, S.J.; Zhang, W.Z.; Li, J.M.; Kong, Y.L. Examining the effects of income inequality on CO2 emissions: Evidence from non-spatial and spatial perspectives. Appl. Ener. 2019, 236, 163–171. [Google Scholar] [CrossRef]
- DOE (Department of Energy, U.S.). Department of Energy Awards over $16 Million for 23 Projects That Will Reduce Carbon Emissions across the Manufacturing Sector. U.S. Department of Energy. 2021. Available online: https://www.energy.gov/eere/articles/department-energy-awards-over-16-million-23-projects-will-reduce-carbon-emissions (accessed on 25 February 2024).
- Dong, F.; Bian, Z.; Yu, B.; Wang, Y.; Zhang, S.; Li, J.; Su, B.; Long, R. Can land urbanization help to achieve CO2 intensity reduction target or hinder it? Evidence from China. Resour. Conserv. Recycl. 2018, 134, 206–215. [Google Scholar] [CrossRef]
- Khan, H.; Weili, L.; Khan, I. Environmental innovation, trade openness and quality institutions: An integrated investigation about environmental sustainability. Environ. Dev. Sustain. 2021, 24, 3832–3862. [Google Scholar] [CrossRef]
- Wu, P.; Song, Y.; Wang, J.; Wang, X.; Zhao, X.; He, Q. Regional variations of credits obtained by LEED 2009 certified green buildings-a country level analysis. Sustainability 2017, 10, 20. [Google Scholar] [CrossRef]
- Wang, T.; Wang, J.; Wu, P.; Wang, J.; He, Q.; Wang, X. Estimating the environmental costs and benefits of demolition waste using life cycle assessment and willingness-to-pay: A case study in Shenzhen. J. Clean. Prod. 2018, 172, 14–26. [Google Scholar] [CrossRef]
- Miliutenko, S.; Åkerman, J.; Bjorklund, A. Energy use and green-house gas emissions during the Life Cycle stages of a road tunnel -the Swedish case norra lanken. Eur. J. Transport Infrastruct. Res. 2012, 12, 39–62. [Google Scholar]
- Zhang, X. Carbon-emission assessment of large shield tunnel based on data-mining methodology. In Proceedings of the World Tunnel Congress 2016, San Francisco, CA, USA, 22–28 April 2016. [Google Scholar]
- Li, X.; Liu, J.; Xu, H.; Zhong, P. Calculation of endogenous carbon dioxide emission during highway tunnel construction: A case Study. In Proceedings of the International Symposium on Water Resource and Environmental Protection, Xi’an, China, 20–22 May 2011; pp. 2260–2264. [Google Scholar]
- Huang, L.; Bohne, R.; Bruland, A.; Drevland, P.; Salomonsen, A. Life Cycle Assessment of Norwegian standard road tunnel. In Proceedings of the 6th International Conference on Life Cycle Management in Gothenburg 2013, Gothenburg, Sweden, 25–28 August 2013. [Google Scholar]
- Li, Q.S.; Li, L.; Bai, Y. CO2 emissions during the construction of a large diameter tunnel with a slurry shield TBM. In Proceedings of the World Tunnel Congress 2013, Geneva, Switzerland, 31 May–7 June 2013; Anagnostou, G., Ehrbar, H., Eds.; Taylor and Francis Group: Abingdon, UK, 2013. [Google Scholar]
- Rodríguez, R.; Pérez, F. Carbon foot print evaluation in tunneling construction using conventional methods. Tunn. Undergr. Space Technol. 2021, 108, 103704. [Google Scholar] [CrossRef]
- Fava, J.A.; Denison, R.; Jones, B.; Curran, M.A.; Vigon, B.W.; Selke, S.; Barnum, J. A Technological Framework for Life-Cycle Assessment; Society of Environmental Toxicology and Chemistry (SETAC) Press: Pensacola, FL, USA, 1991. [Google Scholar]
- Hendrickson, C.T.; Lave, L.B.; Matthews, H.S. Environmental Life Cycle Assessment of Goods and Services: An Input-Output Approach; Resources for the Future: Washington, DC, USA, 2006. [Google Scholar]
- Oladokun, M.G.; Odesola, I.A. Household energy consumption and carbon emissions for sustainable cities e a critical review of modelling approaches. Int. J. Sustain. Built Environ. 2015, 4, 231–247. [Google Scholar] [CrossRef]
- Hitchcock, G. An integrated framework for energy use and behaviour in the domestic sector. Energy Build. 1993, 20, 151–157. [Google Scholar] [CrossRef]
- Sandanayake, M.; Zhang, G.; Setunge, S. Environmental emissions at foundation construction stage of buildings e two case studies. Build. Environ. 2016, 95, 189–198. [Google Scholar] [CrossRef]
- Ahn, C.; Xie, H.; Lee, S.H.; Abourizk, S. Carbon footprints analysis for tunnel construction processes in the preplanning phase using collaborative simulation. In Construction Research Congress 2010: Innovation for Reshaping Construction Practice; ASCE: Reston, VA, USA, 2010; pp. 1538–1546. [Google Scholar] [CrossRef]
- Su, B.; Huang, H.C.; Ang, B.W. Input-output analysis of CO2, emissions embodied in trade: The effects of sector aggregation. Energy Econ. 2010, 32, 166–175. [Google Scholar] [CrossRef]
- Quota Station for Highway Engineering, MOT. JTGT B06-02-2007 Highway Engineering Budget Quota; China Standard Press: Beijing, China, 2007. (In Chinese) [Google Scholar]
- The PRC MOHURD. The Drafting Standard for the Cost Budget of the National Unified Construction Machine Team; China Planning Press: Beijing, China, 2011. (In Chinese) [Google Scholar]
- Chau, C.; Soga, K.; O’Riordan, N.; Nicholson, D. Embodied energy evaluation for sections of the UK Channel Tunnel rail link. Proc. Inst. Civ. Eng. Geotech. Eng. 2012, 165, 65–81. [Google Scholar] [CrossRef]
- National Development and Reform Commission of Climate Change. Chinese Regional Power Grid Baseline Emission Factors in 2016. 2017. Available online: https://www.ndrc.gov.cn/hdjl/yjzq/index.html (accessed on 1 May 2017). (In Chinese)
- IPCC. 2006 IPCC Guidelines for National Greenhouse Gas Inventories; IPCC: Geneva, Switzerland, 2006; Volume 3, pp. 1–40. [Google Scholar]
- GB/T 2589-2008; National Standard of the People’s Republic China. General Principle for Calculation of Total Production Energy Consumption. China Standard Press: Beijing, China, 2008.
- Department of National Account of National Bureau of Statistics. Input-Output Tables of China in 2012; China Statistics Press: Beijing, China, 2015. [Google Scholar]
- Energy Statistics Division of National Bureau of Statistics. China Energy Statistics Yearbook 2013; China Statistics Press: Beijing, China, 2014. [Google Scholar]
- Chen, K.; Duan, H.; Zhang, Y. Research on carbon emission intensity and reduction potential in Guangzhou metro shield tunnel construction phase. Tunn. Constr. 2022, 42, 2064. [Google Scholar]
- Li, Q.; Bai, Y.; Li, L. Study of Influential Factors and Measures for Low Carbonization during the Construction of Shield Tunnels. Mod. Tunn. Technol. 2015, 52, 1–7. [Google Scholar]
- Su, Y.; Zhang, Y.; Duan, H.; Li, Q. Research on Environment impact assessment and emission reduction potential of metro construction: A Case Study in Shenzhen, China. Environ. Eng. 2022, 40, 184–192, 236. [Google Scholar]
P-LCA | I-O-LCA | |
---|---|---|
Advantages | Detailed analysis of specific processes | Objective boundary selection |
Product comparisons | Economy-wide, system LCA | |
Simple principle | Publicly available and fast-update data | |
Easy to achieve | Take indirect inputs into account | |
Identify process improvements | ||
Disadvantages | Subjective boundary selection | Aggregated level of data |
Truncation error | Difficult to identify the process improvements | |
Take no account of indirect inputs | No detailed analysis of specific processes | |
Lack of comprehensive in certain cases | Uncertainty | |
Data-intensive and time-consuming | ||
Poor timeliness | ||
Uncertainty |
Value | Materials (kgCO2) | Materialization (kgCO2) | Materials Transportation (kgCO2) | Tunnelling (kgCO2) | Total (kgCO2) |
---|---|---|---|---|---|
Maximum | 66,286.8 | 1566.5 | 986.0 | 825.7 | 69,665.0 |
Minimum | 66,286.8 | 1566.5 | 1064.0 | 3015.7 | 71,933.0 |
Average | 66,286.8 | 1566.5 | 1025.0 | 1733.0 | 70,611.3 |
Percentage | 93.88% | 2.22% | 1.45% | 2.45% | 100% |
Segment Type | Thickness (mm) | Steel Ratio (kg) | Concrete (m3) | Steel (kg/m3) | Emissions (kgCO2) | Variation |
---|---|---|---|---|---|---|
Ⅰ | 600 | 179.3 | 58.6 | 179.3 | 37,865 | 100% |
Ⅱ | 500 | 179.3 | 50.2 | 179.3 | 31,617 | −16.5% |
Ⅲ | 600 | 161.4 | 58.6 | 161.4 | 35,290 | −6.8% |
Sources | Value | Unit | Emission Factor (kgCO2/Unit) | Emissions (kgCO2) |
---|---|---|---|---|
Electricity | 757 | KWh | 0.923 | 699 |
Diesel | 178 | L | 2.655 | 473 |
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Shi, X.; Kou, L.; Liang, H.; Wang, Y.; Li, W. Evaluating Carbon Emissions during Slurry Shield Tunneling for Sustainable Management Utilizing a Hybrid Life-Cycle Assessment Approach. Sustainability 2024, 16, 2702. https://doi.org/10.3390/su16072702
Shi X, Kou L, Liang H, Wang Y, Li W. Evaluating Carbon Emissions during Slurry Shield Tunneling for Sustainable Management Utilizing a Hybrid Life-Cycle Assessment Approach. Sustainability. 2024; 16(7):2702. https://doi.org/10.3390/su16072702
Chicago/Turabian StyleShi, Xiaodong, Lei Kou, Huiyuan Liang, Yibo Wang, and Wuxue Li. 2024. "Evaluating Carbon Emissions during Slurry Shield Tunneling for Sustainable Management Utilizing a Hybrid Life-Cycle Assessment Approach" Sustainability 16, no. 7: 2702. https://doi.org/10.3390/su16072702