Guidelines For Emergency Ventilation Smoke Control In Roadway Tunnels

"TRB's National Cooperative Highway Research Program (NCHRP) Research Report 836: Guidelines for Emergency Ventilation Smoke Control in Roadway Tunnels presents guidelines for ventilation in roadway tunnels to facilitate human evacuation and emergency responder safety. These guidelines consider tunnel geometrics such as tunnel altitude; physical dimensions (i.e., length, cross section); type of traffic flow (i.e., single or bi-directional flow); and fan utilization and placement. They also consider cargo types and quantities as they pertain to fire heat release rates (FHRRs) and ventilation requirements. The guidelines determine the effects of ventilation on tunnel fires including fire size, and the interaction of firefighting and ventilation system operation. " -- Publisher description

A research project is being conducted at the National Research Council of Canada (NRC) to evaluate the effectiveness of current emergency ventilation strategies to control smoke spread in the event of a fire in two road tunnels. The research study includes numerical and experimental phases. The numerical phase uses Computational Fluid Dynamics (CFD) models to study smoke ventilation in the tunnels. The experimental phase is used to calibrate and to partially validate the chosen CFD models and to provide the necessary initial and boundary conditions. SOLVENT, a CFD model, was used to model ventilation scenarios using existing data. The current paper presents the efforts to validate the CFD model against onsite flow and fire test measurements conducted in a 1.8 km road tunnel. The CFD model includes aerodynamically significant physical features of the tunnel and is customized to provide general roughness replicating the actual roughness in the tunnel.

To investigate the performance of current emergency ventilation strategies for an existing road tunnel system in the event of a fire, a research project is being conducted by the National Research Council (NRC) of Canada. The primary objectives of the study are: a) to assess and validate the ability of emergency ventilation strategies to control smoke spread and minimize the impact of smoke on tunnel users; and b) to recommend guidelines for improving the ventilation operation to maximize intervention effectiveness. This will allow future development of an intelligent ventilation system based on a pre-established ventilation scenario activated using automatic fire detection. The current paper presents the initial investigation of comparing the predictions of a CFD model against the onsite flow measurements conducted in the tunnel. A version of this paper is published in Tunnel Management International Journal, v.7 no. 4, Dec. 2004, pp 1-10.

The ventilation system is an important element for the safety of a tunnel, as well as its investment and operating costs. Investors, operators and designers of road tunnels bear a responsibility for the safety of persons, as well as for important investment decisions. The new Road Tunnel Ventilation Compendium fosters understanding of basic aspects of ventilation in the context of tunnel safety, describes the actual state of the art and shows how to design and realise safer tunnels, at lower costs, with reliably functioning systems.

Like New, No Highlights,No Markup,all pages are intact.

TRB’s National Cooperative Highway Research Program (NCHRP) 415: Design Fires in Road Tunnels information on the state of the practice of design fires in road tunnels, focusing on tunnel fire dynamics and the means of fire management for design guidance.

This book covers a wide range of issues in fire safety engineering in tunnels, describes the phenomena related to tunnel fire dynamics, presents state-of-the-art research, and gives detailed solutions to these major issues. Examples for calculations are provided. The aim is to significantly improve the understanding of fire safety engineering in tunnels. Chapters on fuel and ventilation control, combustion products, gas temperatures, heat fluxes, smoke stratification, visibility, tenability, design fire curves, heat release, fire suppression and detection, CFD modeling, and scaling techniques all equip readers to create their own fire safety plans for tunnels. This book should be purchased by any engineer or public official with responsibility for tunnels. It would also be of interest to many fire protection engineers as an application of evolving technical principles of fire safety.

"This report complements the previous PIARC report "Fire and smoke control in road tunnels" published in 1999 and re-printed in 2004"-P. [4] of cover.