Posts By: Dept. of Civil + Mineral Engineering

Scholarship & Awards Reception Student RSVP

Please fill in the form below to RSVP for the

Scholarships and Awards Reception

on
Tuesday, November 5, 2019
6:30 p.m.

 


Scholarship & Awards Reception RSVP

Please fill in the form below to RSVP for the

Scholarships and Awards Reception

on
Tuesday, November 5, 2019
6:30 p.m.

 

 


U of T Students are connecting communities around the world, one bridge at a time

In June 2018, the University of Toronto Engineers in Action team (formerly Bridges to Prosperity) constructed a 64-metre suspended footbridge over the Gonchu Mayu river in Bolivia, their third bridge project since 2016.

The project began in January 2018 when Engineers in Action was asked to design and build a bridge for Tablas Monte, a village of 140 families located on the tropical slopes of the Andes. Community members had difficulty crossing the nearby river of Gonchu Mayu to reach agricultural lands. The unsafe access has resulted in three fatalities over just three years.

To complete the bridge, the team’s most ambitious and difficult project to date, students faced a long 40-minute commute to the site, requiring them to wake before sunrise and work until after sunset each day. Other challenges include a river profile, which varied greatly from the survey that they originally received; and the necessity to use a deadman anchor in dynamited rock. Despite these challenges, the team completed a bridge of great quality as scheduled, working alongside a local engineer and masons.

The team of six University of Toronto students and three Western university tag-along students completed design, construction, and community engagement plans for the project with the assistance of the parent organization’s technical advisory board. Additionally, engineers from Arup acted as technical supervisors and provided assistance throughout construction.

The teams were fortunate enough to spend the six weeks together with the community of Tables Monte, bonding over and building on the international network of engineers working to solve global infrastructure problems.

“We arrived at the community with a warm-hearted welcome, and an invitation to stay in their old schoolhouse,” said one student organizer.

While in Bolivia, the University of Toronto Chapter worked with teams from Duke University and University College London (UCL), who were constructing a bridge located 15 minutes away from the Gonchu Mayu site.

The bridge was inaugurated with speeches, the traditional breaking of chicha (corn liquor vases), and a night of Bolivian music and dance. The community’s celebration included participation from the governing municipality of Colomi, a locality in Bolivia.

The achievements in Tablas Monte showcase the University of Toronto Chapter’s resilience. Though the club is transitioning from working with Bridges to Prosperity to working with Engineers in Action, the missions and values will remain the same.

The University of Toronto Engineers in Action Chapter is a student organization working to raise awareness for global development and provide students with opportunities to become responsible,

professional engineers through bridge projects. They have previously completed bridge projects in Patzula, Guatemala and Chillcani, Bolivia.

The University of Toronto Chapter will be continuing their mission this year. The students will be working with Western University to build their fifth bridge in Lipez, Bolivia, between May and June 2019. The bridge will be located near a community of 1,000 people, and will help some of the locals reach their farmlands during the rainy summer season. If you would like to be part of our initiative, feel free to contact them at eia.uoft@gmail.com. We are also accepting donations to fund their impactful project through the University of Toronto donation page. Go to https://donate.utoronto.ca/give/show/5, and enter “Engineers in Action – University of Toronto Chapter” in the “Additional Information” box before you check out, and you will receive a tax receipt for your kindness.


U of T CECA/NECA Competes in the 2018 Green Energy Challenge

Aiming to best their third place honours received last year, the University of Toronto student chapter of the Canadian/National Electrical Contractors Association (CECA/NECA) is competing in the 2018 ELECTRI International/NECA Green Energy Challenge.

Leading up to the Green Energy Challenge, the team has hosted several events to spread awareness about sustainable buildings among U of T students.

“Our club has become smarter about the way we explain our work to others,” said President Sneha Adhikari (CIV 1T8+PEY). “Throughout this school year, we have implemented activities to get people engaged in sustainability and make this competition more approachable, allowing our team to grow.”

The U of T team leads include: Rashad Brugmann (CIV 1T9), Noah Cassidy (CIV 1T9), Dorothy Liu (CIV 2T0), Niloufar Ghaffari (CIV 1T9), Shambhavi Niraula (CIV 2T0), Nasteha Abdullahi (CIV 1T9), and Pavani Perera (CIV 1T9).

For this competition, the team is partnering with the Christie Refugee Welcome Centre (CRWC) in Toronto to design a net-zero energy retrofit for their buildings. CRWC is an emergency shelter that warmly welcomes about 300 refugees from around the world each year. This organization is driven by its mission to offer hope and dignity and allow each person they serve to thrive. U of T CECA/NECA is working to contribute to this mission by creating a proposal to both provide cost-saving improvements and to enhance the living experiences of new Canadians. Also, the team is volunteering at CRWC’s children’s programs to get younger generations engaged in becoming stewards of the environment.

The team has conducted an energy audit on site at CRWC. They are using this data (measuring electricity usage, building enclosures, and mechanical systems) in combination with insights from resident interviews to recommend and design improvements for the buildings’ performance. Recently, several members joined CRWC’s Children’s Literacy Program to teach a group of eight children about energy saving, renewable energy, and waste reduction through interactive activities.

Rashad Brugmann (CIV 1T9) expressed the challenges and rewards of his role as Project Manager. “Our work has a strong purpose in terms of sustainable development and green buildings,” he said. “The new focus on net zero energy retrofits has allowed our different subteams to work more collaboratively. We want to create a proposal that will not only do well in the competition but also be valuable and feasible for CRWC.”

The team is currently working hard on finalizing their design proposal for the April 30th deadline, ahead of the 2018 NECA Convention in Philadelphia this fall, where the top teams will present their proposals. Last summer, U of T CECA/NECA’s 2015 Green Energy Challenge design entry was in fact implemented by client, the Good Shepherd Ministries.

They would like to thank the following Faculty members for their continuous support and encouragement: Professor Brenda McCabe, Professor Jeffrey Siegel, Professor Marianne Touchie, and Professor Kim Pressnail.


Acoustic Emission Source Parameters

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At the largest scale, fractures give rise to volcanoes and earthquakes and at engineering scales they form pathways for fluids to flow through and reduce the strength of rock. For these reasons, the study of rock fractures has been a major focus of research in the mining, petroleum and civil engineering industries for decades. To study rock fractures in detail and under controlled conditions, laboratory experiments are conducted where radiated Acoustic Emission (AE) is thought to be analogous to earthquakes.

The focus of this research is to bridge the gap between AE produced during small scale laboratory experiments and larger manmade and natural earthquakes via the absolute calibration of AE sensors. After calibration of our AE sensors, we able to estimate the size and magnitude of AE events induced during a true-triaxial deformation experiment. We found that corner frequency and moment magnitude ranged from 180 < fo < 800 kHz and -7.1 < Mw < -6.2, respectively and all source parameters appeared to obey scaling relationships derived for larger earthquakes.

Related Publications

  • Goodfellow, S.D., and R.P. Young (2014), A laboratory acoustic emission experiment under in situ conditions, Geophysical Research Letters, 41, pp. 3422 – 3430.
  • Goodfellow, S.D., M.H.B. Nasseri, and R.P. Young (2014), “Source parameters of acoustic emissions observed in laboratory and mine environments”, ARMA Conference, June 1 – 4, 2014, Minneapolis, Minnesota, USA, pp 1-7.

Thermo-Hydro-Mechanical Properties of Cobourg Limestone

 

The demand for underground radioactive waste repositories makes  the study of thermo-hydro-mechanical (THM) processes in rocks an increasingly important topic. In collaboration with the Nuclear Waste Management Organization (NWMO) we  conducted triaxial deformation experiments on Cobourg limestone, an argillaceous sedimentary rock found in Southern Ontario, Canada. Experiments were conducted at a constant confining pressure of 12.5 MPa where samples were axially loaded at a constant displacement rate until failure. Samples were heated in situ to 50C, 100C and 150C  to study the thermal effect on deformational response, elastic properties and transport properties.

Our preliminary results show the dependency of mechanical and transport properties to applied temperature and stresses as seen in the displayed figure. Permeability was measured at various stages during heating and deformation using the pulse-decay method. We observed that permeability decreased due to the effect of thermal and differential stresses, which caused compaction of pore spaces and weak bedding planes. Permeability increased after further compression  which led to the initiation and growth of axial cracks parallel to maximum principal stress..

Related Publications

  • Nasseri, M.H.B, S.D. Goodfellow, T.S. Wanne, and R.P. Young (2013), Coupled Thermo-Hydro-Mechanical properties of Cobourg, International Journal of Rock Mechanics and Mining Sciences, (61), 212 – 222.
  • Nasseri, M.H.B, S.D. Goodfellow, T.S. Wanne, and R.P. Young, Thermo- Hydrmo-Mechanical properties of Lindsay limestone: A candidate for Nuclear Waste Repository in Canada, ARMA Conference, June 24 – 27, 2011, Chicago, Illinois, USA.

True-Triaxial Testing

The heart of the Rock Fracture Dynamics Facility is a technologically advanced true-triaxial computer controlled rock deformation system with integral permeability measurement and geophysical imaging capability. For the first time, it is possible to carry out multi-axis thermo-mechanical, geophysical, and hydrological measurements essentially simultaneously on rock specimens ranging from hard rock such as granite to weak rocks undergoing deformation well into the post-failure regime of brittle rocks. The deformation system simulates engineering and geophysical problems to depths of over 4000m at temperatures up to 200C, with maximum loads able to induce fracture and failure in rocks while continuously monitoring changes to the physical properties of the samples. The use of 80mm cubical samples loaded between computer controlled servo-hydraulic rams, provides the high degree of operational flexibility that is needed for the range of instrumentation used in the research, including the monitoring of permeability, seismic velocity, resistivity and acoustic emission in 3D. This allows the growth of fractures to be controlled and monitored over a range of simulated earth-like conditions.

Related Publications

  • Nasseri, M.H.B, S.D. Goodfellow, and L. Lombos, R.P. Young (2014), 3-D Transport and acoustic properties of Fountainebleau sandstone during true-triaxial deformation experiments, International Journal of Rock Mechanics and Mining Sciences 69, 1-18.
  • Nasseri, M.H.B, S.D. Goodfellow, R.P. Young, Investigation of permeability anisotropy and polymodal fracture pattern development using a true-triaxial geophysical imaging cell, AGU Fall Meeting, Dec 9-13, 2013, San Francisco, California, USA.
  • Goodfellow, S.D., M.H.B. Nasseri, and R.P. Young, Evaluation of Wave Propagation Properties during a True-Triaxial Rock Fracture Experiment using Acoustic Emission Frequency Characteristics, AGU Fall Meeting, Dec 9-13, 2013, San Francisco, California, USA.
  • Tabari, M.G., S.D. Goodfellow, M.H.B. Nasseri, and R.P. Young, 3D Anisotropic Velocity Tomography of a Water Saturated Rock under True-Triaxial Stress in the Laboratory, AGU Fall Meeting, Dec 9-13, 2013, San Francisco, California, USA.
  • Young R.P., M.H.B. Nasseri, and L. Lombos, Imaging the effect of the intermediate principal stress on strength, deformation and transport properties of rock using seismic methods, Ture triaxial testing of rocks, CRC Press, Taylor & Francisco Group, Balkema, 2013, 167-179.


Hydraulic Fracturing

Hydraulic fracturing is the initiation and propagation of a fracture by means of fluid pressurization. Hydraulic fracturing has grown in popularity over the past couple of decades in response to increasing public demand for energy alternatives, the discovery of large oil and gas reservoirs in North America and the growing demand for minerals.

The objective of this research is to conduct laboratory scale hydraulic fracturing experiments, which investigate  various hydraulic fracture parameters such as, fluid injection rate, fluid viscosity, stress ratio and rock microfabric. We use deformation measurements, ultrasonic velocity surveys, acoustic emission monitoring, micro computed tomography imaging and thin section analysis to study the micromechanics of hydraulic fracture initiation and propagation and quantify induced fracture geometry.

HydroFrac3

Hydraulic fracture experiments are conducted in a triaxial geophysical imaging cell (ErgoTech). Fluid is injected through a central borehole which can be sealed up to approximately 70 MPa by a multi-O-ring packer system (Designed by Laszlo Lombos). Acoustic Emission is monitored continuously by 18 piezoelectric sensors in direct contact with the rock specimen. Fluid is inject at constant flowrates up to 7.5 mL/min using a servo-controlled hydraulic pump capable of delivering a maximum pressure of 100 MPa.

Related Publications

  • Goodfellow, S.D., M.H.B. Nasseri, and R.P. Young, The influence of injection rate on Hydraulic Fracturing of Westerly granite, ARMA Conference, June 23 – 26, 2013, San Francisco, California, USA.

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