A new experiments-based methodology to define the stability threshold for any vehicle exposed to flooding

Abstract

This is an Accepted Manuscript of an article published by Taylor & Francis Group in Urban water journal on 2017, available online at: http://www.tandfonline.com/doi/full/10.1080/1573062X.2017.1301501A vehicle exposed to flooding, after losing stability, becomes buoyant and may be washed away with potential injuries and fatalities. Such vehicles cause additional disruption to traffic that is already affected by flooding, which may lead to substantial indirect economic impact, especially in urban areas. Therefore, the analysis of the stability of vehicles exposed to flooding is important in order to make decisions to reduce damages and hazards. In this research, based on an experimental campaign that included a range of twelve car models, a new methodology to obtain the stability threshold for any real vehicle exposed to flooding is developed. A stability coefficient (SCmod) is derived with which the vehicles can be sorted by stability against water flows and their stability functions may be determined. The experiments were conducted with three different model scales (1:14, 1:18 and 1:24) and involved analysis of both friction and buoyancy effects, which made this the most comprehensive research study to date. This methodology enables the definition of a stable area in the flow depth-velocity domain for any real vehicle. A tool is provided that decision-makers in the field of urban flood risk management can employ and after defining a design vehicle they can obtain its corresponding stability threshold.Peer ReviewedPostprint (author's final draft

Full‐scale testing of stability curves for vehicles in flood waters

“…Shand et al (2011) provided a comprehensive summary of literature published prior to 2010 which was recently expanded by Martínez-Gomariz et al (2016). Most previous research used small-scale model cars for the assessment of vehicle stability curves (e.g., Bonham & Hattersley, 1967;Gordon & Stone, 1973;Keller & Mitsch, 1992;Kramer, Terheiden, & Wieprecht, 2016;Martínez-Gomariz, Gómez, Russo, & Djordjevi c, 2017;Shu, Xia, Falconer, & Lin, 2011;Toda, Ishigaki, & Ozaki, 2012;Xia, Falconer, Xiao, & Wang, 2013;Xia, Teo, Lin, & Falconer, 2011). The common approach in model scale research of vehicle stability has been to assume a surface friction coefficient, often μ = 0.3 (e.g., Bonham & Hattersley, 1967;Keller & Mitsch, 1992;Kramer et al, 2016), and to measure the flow conditions which displace a model vehicle.…”

Methodology for the damage assessment of vehicles exposed to flooding in urban areas

“…As a general criticism for all three developments, it has to be noted that vehicles may lose their stability even for just 50 cm of water depth or less (Martínez‐Gomariz, Gómez, Russo, & Djordjević, ; Martínez‐Gomariz, Gómez, Russo, & Djordjević, ) and therefore. This vehicle's instability may cause a total vehicle damage and after being washed away may collapse against other urban element, thereby increasing the damages.…”

Methodology to quantify clogging coefficients for grated inlets. Application to SANT MARTI catchment (Barcelona)

“…Therefore, design values for c o should not be related to low flow conditions, but to higher values of Q. On the other hand, in urban areas high hazard conditions for pedestrian and vehicles are mainly related to high flow velocities (and consequently medium and low flow depths y) produced by low roughness of impervious surfaces like streets and sidewalks and/or their high slope (Martínez et al, 2016(Martínez et al, , 2017(Martínez et al, , 2018Russo et al, 2013a) In this framework, it seems justified the adoption of high ratios Q/y for the design of surface drainage systems. If the ratio Q/y = 10 is considered as a reference for high hazard conditions, coefficients for c o are indicated in Table 6, for the tested inlets and associated patterns.…”

“…Flow on the streets in a rainy day depends on several factors like rainfall intensity, urban area, slopes, street cross-sections, and finally the type and number of inlets. Streets have an important role associated to stormwater management and any street must ensure safety for pedestrians (Gómez, Macchione, & Russo, 2011;Martínez, Gómez, & Russo, 2016;Russo et al, 2013a) and vehicular traffic according to a level of service associated to a return period (Martínez, Gómez, Russo, & Djordjevíc, 2017, 2018.…”