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Phase 5 (2012 Deadline)
Capacity Building for Pakistan in Fire Risk Management Venkatesh Kodur, Michigan State University
Muhammad Masood Rafi, NED University of Engineering and Technology Project Overview There has been a rapid influx of people to cities in developing countries in recent years. To meet the demands of a larger population, construction of commercial, industrial, and residential buildings has taken hold in urban areas. These types of buildings are historically vulnerable to hazards such as earthquakes, floods, high winds, etc. However fire is considered one of the biggest threats to the safety of the occupants and the contents of the building. An important factor to address is the absence of studies relating to fire risk management in Pakistan and mechanisms for fire damage assessment of buildings. The project aims to build Pakistan’s capacity in fire risk management through developing a critical mass of professionals, initiating academic programs, and encouraging international collaborations. The team hopes to improve the quality and capacity of Pakistani academic institutions and to benefit the local construction industry. Progress Reports 2014 Summary Report:
The urbanization of big cities has increased many folds in the developing countries owing to a rapid population influx. The development process, which is triggered by this rapid population growth, prompts various types of construction in order to cater for the needs of this population. Commercial, industrial and residential buildings typically constitute a significant proportion of the overall construction. Historically, these are very vulnerable to several possible hazards like earthquakes, floods, high winds, fire, etc. However fire is considered one of the biggest threats to both the building occupants and its contents.
One key challenge in mitigating fire hazard in Pakistan is the absence of studies related to fire risk management and necessary mechanisms for fire damage assessment of buildings. The overall capacity of the Pakistani academia, and public and private sectors to assess fire risk is currently limited. Without significant increases in capacity in this important area, efforts in risk reduction will have limited success. In order to address some of these challenges a Pakistan-US collaboration project was planned with the aim of Capacity Building (in Pakistan) in fire risk management through research and technology transfer activities. The proposed project plans to develop a critical mass of professionals, to help initiating academic programs and to encourage international collaboration. These efforts will help in improving the quality and capacity of Pakistani academic institutions and will benefit local construction industry.
In the first year of the project, a number of activities were undertaken to achieve the objectives as stated above. Two graduate students, one in Pakistan and one in USA and three undergraduate
students in USA were trained in fire related research. Infrastructure development for fire research is being planned at the NED University of Engineering Technology in Pakistan. The Pakistani research team is setting up test equipment for evaluating thermal and mechanical properties of construction materials at elevated temperatures. A meeting between the US and Pakistan research teams which was originally planned for May or June is scheduled in October 2014.
As part of research, “Strategies for evaluating residual capacity of fire exposed concrete structures”, has been selected as one of the main research areas for this project. A literature review to identify knowledge gaps revealed that there is lack of reliable data regarding fire induced degradation of bond in reinforced concrete which is critical in evaluating residual capacity of fire exposed concrete structures. Thus, both experimental and numerical studies have been planned as part of research.
As part of experimental studies, concrete test specimens for determination of fire induced bond degradation have been prepared. Based on knowledge gaps identified through literature review, the test variables to be studied in this experimental program are the effect of concrete strength (NSC and HSC), effect of fiber reinforcement and effect of reinforcement type (deformed and smooth). A finite element based numerical model is being developed in ABAQUS to study the extent of influence on temperature induced bond strength variation on residual capacity of fire exposed reinforced concrete members. In the upcoming year, predictions of the numerical model will be compared against test data to establish validity of the model. Following validation, the model will be utilized to study the effect of varying levels of bond on determining fire resistance of reinforced concrete beams based on different failure limit states. It is expected that results from the numerical model will infer that temperature induced bond degradation has an influence on fire resistance of reinforced concrete beams.
In addition to research, technology transfer activities are being planned in the 2nd and 3rd years of the project. A technology transfer workshop in fire safety is being planned to be held in Pakistan (or in the middle-east region) to educate engineers, practitioners and university researchers from Pakistan and middle-eastern region on all aspects of fire safety. Also, discussions have been initiated to facilitate curriculum development in fire safety engineering in Pakistan.
2015 Summary Report:
In the second year of the project, a number of activities were undertaken to achieve the objectives as stated above. Three graduate students, one in Pakistan and two in USA were trained in fire related research. The Pakistani team sought advice from MSU researchers regarding necessary testing equipment for evaluating mechanical and thermal response of construction materials at high temperatures. In the first year itself, MSU researchers reviewed the available test equipment and provided recommendations based on existing capabilities for fire testing at MSU and elsewhere. Subsequently, based on guidance from the MSU team, the Pakistani team has placed orders for testing equipment that can evaluate mechanical properties of materials at elevated temperatures. Furthermore, in the 2nd year, MSU researchers have provided guidance to Pakistani team on testing equipment and procedures for thermal property tests at high temperatures. Various testing guidelines and codes regarding thermal property evaluation of construction materials at elevated temperatures have been communicated to the Pakistani team. The Pakistan team will soon initiate the procurement process for testing equipment and accessories based on recommendations made by MSU researchers.
A meeting between the US and Pakistan research teams which was originally planned for May or June took place in the third week of October, 2014 (2nd year of the project). Since Prof. Lodi (co-PI) was unable to secure US VISA till September, 2014, Prof. Rafi (PI) alone visited MSU. During the visit, Prof. Rafi visited fire test facilities at MSU accompanied with graduate students and researchers working at The Center for Structural Fire Engineering and Diagnostics (SAFE-D) at Civil Infrastructural Laboratory (CIL), MSU. Also, a mini - seminar on structural fire safety was organized during Prof. Rafi’s visit to MSU. The seminar was focused on introducing on-going fire research at MSU and other leading international institutions to participating researchers. In addition to fire researchers from MSU (US), delegates from India, New Zealand and China were also present at the seminar and discussed emerging trends in fire safety and engineering in their respective countries. Two researchers from Pakistani universities, namely, Dr. Aqeel Ahmed and Dr. Wasim Khaliq, from National University of Sciences and Technology (NUST), Pakistan participated and presented papers at the conference PROTECT2015 -Fifth International Workshop on Performance, Protection & Strengthening of Structures under Extreme Loading was organized at MSU from 28-30th June, 2015. This workshop, although not organized as part of this project, provided a good venue for students working in this project and Pakistani researchers to share their work and learn about the latest research findings of international researchers in the field of fire safety engineering.
Academic programs in “Fire Safety and Engineering (FSE)” are essential for building a critical mass of professionals and researchers who would actively work towards reducing the impact of fire hazard. NED University of Engineering has expressed interest in starting a graduate degree program in FSE in Pakistan. If this is not feasible, NED in short term would like to introduce few courses related to FSE in current degree programs within civil and mechanical engineering fields. Therefore, guidance has been provided to Pakistani collaborators for development of academic programs in fire safety engineering. A detailed survey of existing degree programs and courses in various universities around the world was conducted. Furthermore, in-depth information on course structure, topics and content offered in these programs was also collected. Details of compiled course content and syllabi were sent to Pakistani collaborators for initiating new courses in their graduate curriculum.
As part of research, an approach for evaluating residual capacity of fire exposed beams has been developed. The residual capacity is evaluated using a three stage procedure, namely, ambient response analysis at room temperature (Stage 1), elevated temperature analysis during fire exposure (Stage 2) and finally, post-fire residual analysis after cooling down of the concrete member (Stage 3). This approach has been implemented using a numerical model developed in the finite element based computer software ABAQUS. The developed model accounts for various parameters including load level, temperatures experienced within the beam during fire exposure, the rate of cooling and strength recovery after fire.Based on the results of analysis it was found that RC beams retain significant residual flexural capacity after exposure to most design fire scenarios wherein the peak temperatures experienced by rebars remain below 500oC.
As part of experimental studies, first phase of testing to evaluate fire induced bond degradation between reinforcement and concrete was carried out. This testing is being carried out to establish bond stress-slip curves and failure modes for different types of concrete at room temperature conditions. Characterizing the bond properties at room temperature provides benchmark data for comparing extent of temperature induced degradation in subsequent high temperature tests. Also, due to the unique nature of test specimens and setup, testing at room temperature ensures the reliability and accuracy of obtained results. After establishing the room temperature bond properties, both ‘elevated temperature (hot) tests’ and ‘residual (cold) tests’ will be carried out in the upcoming period. Data from these tests will be utilized to develop models for predicting temperature induced bond degradation between reinforcement and concrete and therefore lead to a more rational performance of RC structures under fire conditions. A finite element based numerical model is developed in ABAQUS to study the extent of influence on temperature induced bond degradation on fire performance of reinforced concrete members. Results from preliminary studies indicates that incorporating temperature-dependent local bond-slip behavior in analysis leads to more accurate predictions of deflections observed in RC beams during fire exposure.
In the next cycle (3rd year) of the project, a more sophisticated numerical model that can incorporate various parameters, especially fire induced bond degradation, would be developed for evaluating residual capacity of fire exposed reinforced concrete members. Also, experiments would be conducted to evaluate interfacial bond characteristics between reinforcing steel and concrete at high temperatures. In addition to research, a technology transfer workshop in fire safety is being planned to be held in Pakistan (or in the middle-east region) to educate engineers, practitioners and university researchers from Pakistan and middle-eastern region on all aspects of fire safety.
2016 Summary Report:
In the third year of the project, a number of activities were undertaken to achieve the objectives as stated above. Four graduate students, one in Pakistan and three in USA, were trained in fire related research. The training received by students at MSU encompassed use of sophisticated test equipment for evaluating thermal properties of constructional materials, undertaking fire resistance tests on structural members, and utilization of advanced computational programs for studying response of structures exposed to fire. Specifically, students gained experience in the application of ABAQUS (advanced finite element software) to model the response of structural systems exposed to fire. Furthermore, gained experience in conducting full scale fire tests on structural members as well as high temperature material property characterization tests. Moreover, students developed communication skills through technical presentations and writing papers based on the research undertaken. The Pakistani researchers have also trained the recruited MS student in various aspects of fire research.
As part of technology transfer initiative on various aspects of fire safety, a web based seminar was planned in the third year for students and researchers in Pakistan. Under this initiative, a special lecture by PI Dr. Kodur, on the role of fire issues in the collapse of a number of buildings during 9/11 WTC disaster, and of the engineering lessons learnt from these collapses, was recorded and sent to Pakistani PI for showing to students and researchers at NED University and elsewhere. Also, Prof. Kodur (US PI) helped American University of Sharjah (AUS) to organize the “Third Mini Symposium and Workshop on Design for Fire Safety in Buildings and Built Infrastructure” at American University of Sharjah (AUS) in Sharjah, UAE. US and Pakistani PIs delivered presentations at this fire safety symposium which were well received by attendees of this symposium and helped showcase research undertaken as part of this project.
US and Pakistani researchers met at American University of Sharjah (AUS) in Sharjah, UAE for the second annual meeting for this project. Prof. Kodur, PI from US, as well as Profs. Rafi and Lodi, PIs from Pakistan, took part in this meeting held on 12th March 2016. Different tasks pertaining to various project objectives ranging from research activities, knowledge transfer and curriculum development were reviewed at this meeting. Furthermore, possibilities of future interaction and collaboration between researchers at MSU (US) and NED University (Pakistan), beyond the project period and towards capacity building in Pakistan for fire safety, were explored. Furthermore, Pakistani PIs requested US research team to develop a simplified guidance document for deploying in Pakistan for inspecting fire damaged buildings in Pakistan, during this meeting. It was felt that such a document would be highly beneficial for capacity building for Pakistan in fire risk management.
At present, there are limited approaches and guidelines to assess the extent of fire induced damage in a structure following a fire incident. A detailed literature review was undertaken on thumb rules that can be used to quantify fire damage to a concrete structure. Some of the key findings from the research undertaken as part of this project as well as that is available in literature, are being summarized in the form of a design guide to assess fire damage in concrete structures. The document will contain detailed steps and thumb rules on conducting preliminary inspection, damage assessment, and detailed testing and capacity assessment after a fire incident in a building. Such a document will help practitioners, engineers and firefighters to inspect fire damaged structures and also provide insight into repair strategies for reinstating fire damaged structures.
As part of research, both experimental and numerical studies for evaluating residual response of fire damaged structures were conducted. Full scale fire tests, followed by residual capacity test, on two fire damaged reinforced concrete (RC) beams were conducted. The tests yielded valuable insight into the response of fire damaged RC beams. It was seen that RC beams retain significant residual capacity even after being exposed to moderate or severe design fire. At the material level, simplified bilinear bond stress-slip relations varying with temperature were proposed based on data obtained from high temperature bond tests. Also, a detailed numerical model that can incorporate temperature induced bond degradation was also developed. This model was applied to analyze fire performance of RC beams which indicated that variations in interfacial bond between rebar and concrete has an influence on the fire response of RC beams, and incorporating bond-slip relations, specific to concrete type, is critical in evaluation residual capacity of fire damaged RC structures.
This project was approved in early October 2013 but there were delays in hiring students and setting up accounts for project expenditure within the institutions. Further delays were caused when Pakistani PIs could not get US VISA in time and project meetings could not take place in the first year as planned originally. It was felt during the recent project meeting between US and Pakistani PIs that while significant progress has been made, some of the project tasks require further work. Also, as part of capacity building in fire risk management, Pakistani PIs requested US research team to develop of a guidance document for rapid assessment of fire damaged concrete structures in Pakistan. Work on this document is currently underway at MSU. Additional fire tests are needed to generate data for validating the applicability of these guidelines to wide ranging fire damage scenarios encountered in Pakistan. These tests would require fabrication of test specimens as well as extensive planning for conducting the necessary fire tests. In addition to research related activities, video lectures with focus on structural fire engineering will be recorded and sent to Pakistani researchers as part of technology transfer initiative. A “No-Cost-Extension” has been requested since these tasks are expected to take another 12 to 18 months to complete. Moreover, since significant financial support was available from MSU particularly for hiring students, the remaining funds in the project will be expended in various aforementioned tasks in the next cycle (4th year) of the project.
2017 Summary Reports:
A number of activities were undertaken in the fourth year of the project to achieve stated objectives of the project. One graduate student in Pakistan and three graduate students in USA gained extensive experience in fire related research by working on various tasks associated with this project. The students were trained in utilizing sophisticated test equipment for both material characterization at elevated temperatures, and structural level fire tests. Students also gained experience in applying advanced finite element based computer software (ABAQUS) to predict response of structural members exposed to fire. In addition, students improved their communication skills through technical presentations and by writing papers based on research work carried out as part of this project. The Pakistani researchers have also trained the recruited graduate student in various aspects of fire research.
A project meeting between the US and Pakistani research teams took place in during November 7th to 10th, 2016 to discuss progress, and to plan remaining tasks of this project. Different tasks pertaining to various project objectives ranging from research activities, knowledge transfer and curriculum development were reviewed at this meeting. Furthermore, possibilities of future interaction and collaboration between researchers at MSU (US) and NED University (Pakistan), beyond the project period and towards capacity building in Pakistan for fire safety, were explored. Furthermore, US research team updated the Pakistani visitors on the simplified guidance document for inspecting fire damaged buildings in Pakistan, during this meeting. This document would be highly beneficial for capacity building for Pakistan in fire risk management.
As part of research, both experimental and numerical studies for evaluating residual response of fire damaged structures were conducted. Full scale fire tests, followed by residual capacity test, were conducted on two reinforced concrete (RC) columns. The tests yielded valuable insight into the response of fire damaged RC columns. It was seen that the RC columns retained significant residual capacity even after being exposed to 90 minutes and 120 minutes of heating under fire respectively. At the material level, non-destructive ultrasonic pulse velocity (UPV) tests were carried out on to evaluate extent of temperature induced damage in fire exposed concrete structures. Also, a detailed numerical model developed to evaluate residual capacity of fire damaged structures, was extended to incorporate the effect of temperature induced bond degradation. This model was applied to analyze fire performance of RC beams, as well as residual response of fire damaged RC beams, which indicated that variations in interfacial bond between rebar and concrete has an influence on the fire response of RC beams. Thus, incorporating bond-slip relations, specific to concrete type, is critical in evaluation residual capacity of fire damaged RC structures.
At present, there are limited approaches and guidelines to assess the extent of fire induced damage in a structure following a fire incident. To this end, a comprehensive approach, employing visual screening, non-destructive testing, as well as simplified and (or) advanced analysis methods, was developed to assess residual capacity of concrete structures following fie exposure. This document will be sent to Pakistani researchers for deploying in the field for assessing fire damaged concrete structures. In addition, limited guidelines for evaluating thermal and mechanical properties of construction materials in Pakistan. Therefore, researchers at MSU developed detailed guidelines for such tests were developed based on international codes and standards. Further, the applicability of these guidelines was demonstrated through tests conducted at MSU. Such guidelines will form the basis for conducting further tests, and developing temperature dependent property relations for construction materials that can be incorporated in Pakistani codes and standards.
This project was approved in October 2013, which is off-cycle from both Fall (beginning in August) and Spring (beginning in January) academic semesters, causing delays in hiring of students and setting up of accounts for project expenditures. Further delays were caused when Pakistani PIs could not obtain US VISA in time and project meetings could not take place in the first year as planned originally. Additionally, there was equipment (fire furnace needed for undertaking experiments) breakdown, imposing further delays on the project.
Nonetheless, both the Pakistani and US research teams have achieved said goals of the project towards capacity building for fire risk management in Pakistan.
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