Full Text:   <930>

Summary:  <518>

CLC number: TU998

On-line Access: 2015-02-03

Received: 2014-05-28

Revision Accepted: 2014-12-17

Crosschecked: 2015-01-22

Cited: 0

Clicked: 1647

Citations:  Bibtex RefMan EndNote GB/T7714

 ORCID:

Wei-yun Shao

http://orcid.org/0000-0001-8896-8355

-   Go to

Article info.
Open peer comments

Journal of Zhejiang University SCIENCE A 2015 Vol.16 No.2 P.117-130

http://doi.org/10.1631/jzus.A1400154


Assessment of the safe evacuation of people walking through flooding staircases based on numerical simulation


Author(s):  Wei-yun Shao, Li-jie Jiang, Lei Fang, David Z. Zhu, Zhi-lin Sun

Affiliation(s):  College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China; more

Corresponding email(s):   shaowy@zju.edu.cn, fanglei1999@126.com

Key Words:  Staircase, Rest platform, Flood, Evacuation, Computational fluid dynamics (CFD) simulation


Wei-yun Shao, Li-jie Jiang, Lei Fang, David Z. Zhu, Zhi-lin Sun. Assessment of the safe evacuation of people walking through flooding staircases based on numerical simulation[J]. Journal of Zhejiang University Science A, 2015, 16(2): 117-130.

@article{title="Assessment of the safe evacuation of people walking through flooding staircases based on numerical simulation",
author="Wei-yun Shao, Li-jie Jiang, Lei Fang, David Z. Zhu, Zhi-lin Sun",
journal="Journal of Zhejiang University Science A",
volume="16",
number="2",
pages="117-130",
year="2015",
publisher="Zhejiang University Press & Springer",
doi="10.1631/jzus.A1400154"
}

%0 Journal Article
%T Assessment of the safe evacuation of people walking through flooding staircases based on numerical simulation
%A Wei-yun Shao
%A Li-jie Jiang
%A Lei Fang
%A David Z. Zhu
%A Zhi-lin Sun
%J Journal of Zhejiang University SCIENCE A
%V 16
%N 2
%P 117-130
%@ 1673-565X
%D 2015
%I Zhejiang University Press & Springer
%DOI 10.1631/jzus.A1400154

TY - JOUR
T1 - Assessment of the safe evacuation of people walking through flooding staircases based on numerical simulation
A1 - Wei-yun Shao
A1 - Li-jie Jiang
A1 - Lei Fang
A1 - David Z. Zhu
A1 - Zhi-lin Sun
J0 - Journal of Zhejiang University Science A
VL - 16
IS - 2
SP - 117
EP - 130
%@ 1673-565X
Y1 - 2015
PB - Zhejiang University Press & Springer
ER -
DOI - 10.1631/jzus.A1400154


Abstract: 
A numerical model was developed to evaluate the possibility of people walking in a flooding flow on a staircase with rest platforms. Commercial software was used and validated by experimental data for flows on staircases and stepped spillways. The effects of the rest platform, the staircase slope, and the staircase pattern on the flooding flow characteristics are discussed. A comparison of staircases with or without rest platforms shows that the flow velocity increases significantly downstream of the rest platform on a straight-run type, which would have negative effects on the safe evacuation of people walking through a flooding staircase. The slope of the staircase, ranging from 26.6° to 30°, has less effect on safe evacuation. A comparison of flows on straight-run (with or without rest platforms), 90°-turn and 180°-turn staircases (with rest platforms) shows that the rest platforms on the latter two staircases could induce a redistribution of the flow field on the rest platform and downstream. The distribution of evacuation indicators along the longitudinal planes of those staircases indicates that a 90°-turn staircase or a straight staircase without rest platform would be the first choice for trapped people evacuating from underground spaces.

基于数值模拟的阶梯水流中行人安全撤离研究

目的:研究不同形式阶梯水流中被困人员的安全撤离,为地下空间水侵灾害脆弱性评价及防灾避灾提供参考。
方法:根据试验结果和数值模型的相关理论构建数值模型,验证数值模拟阶梯水流流场的可靠性和合理性,并基于数值模型的灵活性和可变性,模拟休息平台、阶梯坡度和阶梯形态对水流流场的影响,据此对有无休息平台、不同阶梯坡度和不同阶梯形态下阶梯水流流态、流速分布以及对被困人员的安全撤离的影响进行深入分析。
结论:中间休息平台的存在增加了被困人员撤离的风险;阶梯坡度对阶梯上水流的水力特性影响很小;L型阶梯中间休息平台有利于减小平台下游撤离风险,被困人员可以优先选择L型阶梯或者不含休息平台的直线型阶梯撤离。

关键词:阶梯;休息平台;水侵灾害;逃生;数值模拟

Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article

Reference

[1]Ariff, M., Salim, S.M., Cheah, S.C., 2009. All Y+ approach for dealing with turbulent flow over a surface mounted cube: part II-high Reynolds number. 7th International Conference on CFD in the Mineral and Process Industries, Australia.

[2]Ashley, R.M., Balmforth, D.J., Saul, A.J., et al., 2005. Flooding in the future-predicting climate change, risks and responses in urban areas. Water Science and Technology, 52:265-273.

[3]Boes, R.M., Hager, W.H., 2003. Two-phase flow characteristics of stepped spillways. Journal of Hydraulic Engineering, 129(9):661-670.

[4]BUEDRI (Beijing Urban Engineering Design & Research Institute Co., Ltd.), 2003. Code for Design of Metro. China Planning Press (in Chinese).

[5]Cain, P., 1978. Measurements within self-aerated flow on a large spill-way. Research Report, Department of Civil Engineering, University of Canterbury, New Zealand, p.650.

[6]Chanson, H., 1994. Hydraulics of skimming flows over stepped channels and spillways. Journal of Hydraulic Research, 32(3):445-460.

[7]Chanson, H., Toombes, L., 2001. Experimental investigations of air entrainment in transition and skimming flows down a stepped chute: application to embankment overflow stepped spillways. Department of Civil Engineering, University of Queensland.

[8]Chanson, H., Toombes, L., 2003. Strong interactions between free-surface aeration and turbulence in an open channel flow. Experimental Thermal and Fluid Science, 27(5):525-535.

[9]Chen, Q., Dai, G., Liu, H., 2002. Volume of fluid model for turbulence numerical simulation of stepped spillway overflow. Journal of Hydraulic Engineering, 128(7):683-688.

[10]Cheng, X., Chen, Y., Luo, L., 2006. Numerical simulation of air-water two-phase flow over stepped spillways. Science in China Series E: Technological Sciences, 49(6):674-684.

[11]Felder, S., Chanson, H., 2009. Energy dissipation, flow resistance and gas-liquid interfacial area in skimming flows on moderate-slope stepped spillways. Environmental Fluid Mechanics, 9(4):427-441.

[12]Felder, S., Chanson, H., 2011. Air-water flow properties in step cavity down a stepped chute. International Journal of Multiphase Flow, 37(7):732-745.

[13]Gonzalez, C.A., Takahashi, M., Chanson, H., 2008. An experimental study of effects of step roughness in skimming flows on stepped chutes. Journal of Hydraulic Research, 46(S1):24-35.

[14]Gotoh, H., Ikari, H., Sakai, T., et al., 2006. Computational mechanics of a force on a human leg in flow over a underground staircase in urban flood. Annual Journal of Hydraulic Engineering, JSCE, 60:865-870 (in Japanese).

[15]ICC (International Code Council), 2011. International Building Code (IBC). ICC (Distributed by Cengage Learning), 500 New Jersey Avenue, NW, Washington, DC 20001.

[16]Inoue, K., Toda, K., Nakai, T., et al., 2003. On the inundation process in the underground space. Annuals of Disaster Prevention Research Institute, Kyoto University B, 46: 263-273 (in Japanese).

[17]Ishigaki, T., Toda, K., Baba, Y., et al., 2005. Experimental study on evacuation from underground space by using real size models. Annuals of Disaster Prevention Research Institute, Kyoto University B, 48:639-646 (in Japanese).

[18]Ishigaki, T., Kawanaka, R., Onishi, Y., et al., 2009. Assessment of safety on evacuating route during underground flooding. Advances in Water Resources and Hydraulic Engineering, 1-6:141-146.

[19]Jiang, L.J., Shao, W.Y., Zhu, D.Z., et al., 2014. Forces on surface-piercing vertical circular cylinder groups on flooding staircase. Journal of Fluids and Structures, 46:17-28.

[20]Kositgittiwong, D., Chinnarasri, C., Julien, P.Y., 2013. Numerical simulation of flow velocity profiles along a stepped spillway. Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering, 227(4):327-335.

[21]Kotani, K., Ishigaki, T., Suzuki, S., et al., 2012. Evaluation for emergency escape during stair climbing in a simulated flood evacuation. Network of Ergonomics Societies Conference (SEANES), Southeast Asian, IEEE, p.1-5.

[22]Launder, B.E., Spalding, D., 1974. The numerical computation of turbulent flows. Computer Methods in Applied Mechanics and Engineering, 3(2):269-289.

[23]MOHURD (Ministry of Housing and Urban-rural Development of the People’s Republic of China), 2005. Code for Design of Civil Buildings. Chinese Architecture and Building Press, Beijing (in Chinese).

[24]Ohtsu, I., Yasuda, Y., Takahashi, M., 2004. Flow characteristics of skimming flows in stepped channels. Journal of Hydraulic Engineering, 130(9):860-869.

[25]Qian, Z., Hu, X., Huai, W., et al., 2009. Numerical simulation and analysis of water flow over stepped spillways. Science in China Series E: Technological Sciences, 52(7):1958-1965.

[26]Relvas, A.T., Pinheiro, A.N., 2011. Velocity distribution and energy dissipation along stepped chutes lined with wedge-shaped concrete blocks. Journal of Hydraulic Engineering, 137(4):423-431.

[27]Salim, S.M., Cheah, S., 2009. Wall Y strategy for dealing with wall-bounded turbulent flows. Proceedings of the International MultiConference of Engineers and Computer Scientists, Hong Kong.

[28]Schubert, J.E., Sanders, B.F., 2012. Building treatments for urban flood inundation models and implications for predictive skill and modeling efficiency. Advances in Water Resources, 41:49-64.

[29]Shao, W.Y., 2010. Critical rainfall intensity for safe evacuation from underground spaces with flood prevention measures. Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering), 11(9):668-676.

[30]Shao, W.Y., Jiang, L.J., Zhang, Y.P., et al., 2014. Hydraulic features of air-water mixture flow on staircase with rest platforms. Journal of Hydraulic Engineering, 140(6):04014016.

[31]Simões, A.L.A., Schulz, H.E., De Melo Porto, R., 2010. Stepped and smooth spillways: resistance effects on stilling basin lengths. Journal of Hydraulic Research, 48(3):329-337.

[32]Takahashi, M., Ohtsu, I., 2012. Aerated flow characteristics of skimming flow over stepped chutes. Journal of Hydraulic Research, 50(4):427-434.

[33]Taylor, J., Lai, K.M., Davies, M., et al., 2011. Flood management: prediction of microbial contamination in large-scale floods in urban environments. Environment International, 37(5):1019-1029.

[34]Tongkratoke, A., Chinnarasri, C., Pornprommin, A., et al., 2009. Non-linear turbulence models for multiphase recirculating free-surface flow over stepped spillways. International Journal of Computational Fluid Dynamics, 23(5):401-409.

[35]Yoneyama, N., Toda, K., Aihata, S., et al., 2009. Numerical analysis for evacuation possibility from small underground space in urban flood. Advances in Water Resources and Hydraulic Engineering, p.107-112.

Open peer comments: Debate/Discuss/Question/Opinion

<1>

ganyu<yulin>

2015-02-08 18:21:59

A numerical model was developed to evaluate the possibility of people walking in a flooding flow on a staircase with rest platforms.

Please provide your name, email address and a comment





Journal of Zhejiang University-SCIENCE, 38 Zheda Road, Hangzhou 310027, China
Tel: +86-571-87952783; E-mail: cjzhang@zju.edu.cn
Copyright © 2000 - Journal of Zhejiang University-SCIENCE