Life-cycle low-carbon design and assessment of UHPC beams integrating flexural capacity requirements

Abstract

The excellent mechanical properties of ultra-high performance concrete (UHPC) will reduce the cross-sectional size of UHPC beams, resulting in a decrease in the amount of UHPC and the carbon emission. However, the large amount of cement in UHPC can lead to significant carbon emissions during the production process. Few existing studies have paid attention to the relationship between the mechanical properties of UHPC beams and carbon emissions. In this study, a 30 m prestressed UHPC beam was taken as the research object. Based on the analysis of the actual force, a cross-section and reinforcement scheme considering its mechanical properties was formulated. The influence of material ratio and different design parameters on its bending moment capacity was then analyzed. Additionally, a carbon emission calculation model for the entire life cycle of the UHPC beam was constructed, and the carbon emissions of the 30 m UHPC beam under different material ratios were obtained. On this basis, the carbon strength of UHPC beams was introduced and analyzed. The results show that the structural carbon strength of the 30 m UHPC beam is better when the fiber volume fraction is 2%, the reinforcement ratio is 1.3%, and the UHPC compressive strength is between 140–160 MPa. In addition, a formula for calculating the structural carbon strength of the 30 m UHPC beam with different material ratios was obtained by machine learning. Through the formula, the carbon emissions in the entire life cycle of the 30 m UHPC beam after meeting the requirements of the bending moment capacity can be determined.

Keywords

UHPC / Life-cycle assessment / Carbon emissions / Carbon strength / Bending moment capacity

References

[1] Newell, P., & Phylipsen, D. (2018). Implications of the IPCC Special Report on 1.5 degrees for scaling up Nationally Determined Contributions (NDCs) under the Paris Agreement. Climate Strategies. http://www.jstor.org/stable/resrep21727

[2] Wang CQ, Chen Y, Chi CY, Tao Y, Li XB, Jiang XD. Calculation method of carbon emission flow in power system based on power flow distribution matrix. Science Technology and Engineering, 2022, 12: 4835-4842

[3] Pathak, M., Slade, R., Shukla, P. R., Skea, J., Pichs-Madruga, R., Ürge-Vorsatz, D. (2022). Climate Change 2022 Mitigation of Climate Change: Technical Summary. In Shukla, P. R., et al. (Eds.), Climate Change 2022: Mitigation of Climate Change. Contribution of Working Group III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press. https://doi.org/10.1017/9781009157926.002

[4] Gan VL, Cheng JCP, Lo MC. A comprehensive approach to mitigation of embodied carbon in reinforced concrete buildings. Journal of Cleaner Production, 2019, 229: 582-597.

[5] Shi C, Wu Z, Xiao J, Wang D, Huang Z, Fang Z. A review on ultra high-performance concrete: Part I. Raw materials and mixture design. Construction and Building Materials, 2015, 101: 741-751.

[6] Haber, Z. B., De la Varga, I., Graybeal, B. A., Nakashoji, B., & El-Helou, R. (2024). Properties and behavior of UHPC-class materials. United States: Federal Highway Administration, Office of Infrastructure.

[7] Yoo DY, Shin W. Improvement of fiber corrosion resistance of ultra-high-performance concrete by means of crack width control and repair. Cement and Concrete Composites, 2021, 121104073

[8] Ding C, Jia ZJ, Wang ZH, Ding YX. UHPC carbon emission control potential based on life cycle assessment. Journal of the Chinese Ceramic Society, 2023, 10: 1242-1251

[9] Kien TT. Comparison of energy consumption, CO2 emissions between normal concrete and UHPC in rural bridge application. Journal of Science and Technology in Civil Engineering (STCE), 2023, 17: 168-179.

[10] Dong Y. Performance assessment and design of ultra-high performance concrete (UHPC) structures incorporating life-cycle cost and environmental impacts. Construction and Building Materials, 2018, 167: 414-425.

[11] Shao Y, Parks A, Ostertag CP. Carbon footprint between steel-reinforced concrete and UHPC beams. Journal of Structural Engineering, 2023, 149(3): 06023001.

[12] Wang YZ, Fu CG. Abaqus structural engineering analysis and example explanation, 2010China Building Industry Press

[13] Hu YQ, Qiu JR, Li ZJ, Yao YM, Liu JP, Wang JQ. Shear strength prediction method of the UHPC keyed dry joint considering the bridging effect of steel fibers. Journal of Engineering Structures, 2022, 255113937

[14] Zhang Z, Shao XD, Li WG, Zhu P, Chen H. Axial tensile behavior test of ultra-high performance concrete. China Journal of Highway and Transport, 2015, 28(8): 50-58

[15] Chen L, Graybeal BA. Modeling structural performance of ultrahigh performance concrete I-girders. Journal of Bridge Engineering, 2012, 17(5): 754-764.

[16] Ministry of Transport of the People's Republic of China. General specifications for design of highway bridges and culverts, 2015China Communications Press

[17] Guo Z, Wang Q, Zhao N, Dai R. Carbon emissions from buildings based on a life cycle analysis: Carbon reduction measures and effects of green building standards in China. Low-carbon Mater. Green Constr., 2023, 1: 9.

[18] Burgess AA, Brennan DJ. Application of life cycle assessment to chemical processes. Chemical Engineering Science, 2001, 56(8): 2589-3260.

[19] Fang K. A framework for quantification and integration of environmental footprints: From the perspective of life cycle assessment. Acta Ecologica Sinica, 2016, 36(22): 7228-7234

[20] Ministry of Housing and Urban-Rural Development of the People's Republic of China. Standard for building carbon emission calculation, 2019China Architecture & Building Press

[21] Wei, M. Z., Lin, M. Q., Xie, Q., Hu, Z. W., & Yu, Y. (2024). Analysis and calculation of carbon emissions from recycled aggregate concrete throughout its entire life cycle. Concrete, 1–10.

[22] Xu S. The calculation method of life cycle carbon emissions of bridges with different structural materials is studied. Wuhan University of Technology, 2012, 11: 58

[23] Wang Q, Wang S. Why does China’s carbon intensity decline and India’s carbon intensity rise? A decomposition analysis on the sectors. Journal of Cleaner Production, 2020, 265121569

[24] Zhang F, Wang C, Liu J, Zou X, Sneed LH, Bao Y, Wang L. Prediction of FRP-concrete interfacial bond strength based on machine learning. Journal of Engineering Structures, 2023, 274115156

Funding

Anhui Provincial Department of Science and Technology(2308085QE185)

National Natural Science Foundation of China(No.52308129)

Anhui Provincial Department of Education(2023AH050175)

RIGHTS & PERMISSIONS

The Author(s)