Publications | Professional Activity | Awards | Graduate Students | Projects
- Stability of Liners Used to Repair Damaged Sewers and Water Pipes.
Outline: Polymer liners fitted within damaged sewers will respond to external fluid loads, and to changes in earth loads as a result of vehicle loads on the ground surface or deterioration of the backfill in the vicinity of the buried structure. Past work has established the role of damaged pipe and liner geometry on both resistance to buckling under external fluid pressures, and local bending under external earth pressures. Laboratory testing and nonlinear finite element analysis is being used to understand how stability is influenced by erosion voids in the vicinity of the buried sewer pipe. Limit states are now being investigated for water and gas supply pipes repaired using cast in place liners, considering the influence of internal pressure, ground movements and soil-pipe-liner interaction.
Funding: NSERC Discovery Grant, NSERC Strategic Research Grant, Hamilton City.
Collaborators : A. Fam, E. Allouche.
Duration: 1996 - present
Students: K. El Sawy (PhD, 1996), J. Lee (MSc, 2002) , M. Law (PhD, 2004), Z. Tan (MSc, 2007), N. Ampiah (MSc, 2008), M. Brown (PhD in progress).
- Frost damage to buried pipe infrastructure
Outline: Analytical and experimental work is being used to understand stability limit states for buried infrastructure responding to frost loads. Thermo-viscoelastic analysis has been developed for HDPE to permit calculation of temperature-induced deformations or stresses. Three dimensional finite element analyses are being used to examine cast iron pipe damage as a result of differential ground movements caused by different levels of frost susceptibility..
Funding: NSERC Discovery grant
Collaborators: M. Green, A. Take
Duration: 2003 - present
Students: H. Mwana'gonze (MSc, 2004), S. Trickey (MSc, 2005), M. Sarai (PhD in progress)
- Soil-structure Interaction During HDPE Pipe Installation Using Pipe Bursting
Outline: Pipe bursting involves expansion to break and displace existing brittle pipes, and pulling into place of a replacement HDPE pressure pipe. Analysis of the cavity expansion and contraction is being used to investigate radial pressures on the HDPE replacement pipe to permit estimation of pulling forces, peak stresses and maximum pulling lengths.
Funding: NSERC Strategic Research and Discovery Grants
Collaborator: R.W. Brachman
Duration: 1999 - present
Student: V. Fernando (MESc, 2002), M. Nkemitag (PhD, 2007), B. Lapos (MSc, 2004), H. McLeod (MSc, 2008), J. Cholewa (PhD, 2009), K. Rahman (PhD in progress)
- Pulling Forces and Hydraulic Fracture During Horizontal Directional Drilling
Outline: Horizontal directional drilling involves opening of a pilot hole using a horizontally directed drilling rig, hole expansion using a back-reamer, and pulling into place of a new HDPE pipe. Field measurements and finite element modeling are being used to investigate pulling forces on HDPE pipes pulled-into-place. Finite element studies are examining both blowout and brittle fracture of soil surrounding the borehole due to excessive mud pressures.
Collaborators: E.N. Allouche (Louisiana Tech), and R.W. Brachman
Funding: NSERC Discovery and Strategic Research Grants
Duration: 1999 - present
Students: M. Baumert (PhD, 2003), M. Kennedy (MSc, 2004), A. Chehab (PhD, 2008) , H. Xia (PhD, 2008), J. Cholewa (PhD, 2009)
- Analysis of pipe and culvert coupling systems
Outline: High density polyethylene pipes used for stormwater sewers and highway culverts are fitted with a variety of mechanical and pressure rated couplings. The design of these couplings depends on the interaction of the two pipes, as well as the mechanical coupler and/or rubber gasket. Finite element analysis is being developed for use in coupling design, and specific connection problems such as vertical forces at vertical risers are being investigated.
Funding: NSERC Discovery Grant, Ipex, US DOTs through the National Collaborative Highway Research Program.
Collaborators: H. Sezen (Ohio State University), P. Fox (UCSD)
Duration: 2002 - present
Student: J. Chan (MSc, 2002), J. Ye (PhD, 2008), M. Balkaya (PhD, 2010), D. Becerril (PhD in progress)
PAST ENGINEERING PROJECTS
- Limit States Design of Thermoplastic Culverts
Outline: Laboratory testing to define limit states (local bending and local buckling), 2D and 3D finite element analysis and evaluations of published field studies are being used to develop design methods for high density polyethylene and polyvinyl chloride culvert products (being incorporated in the AASHTO Highway Bridge Design Code).
Funding: NCHRP (US Academy of Sciences)
Collaborators: T.G. McGrath at Simpson, Gumpertz and Heger, Arlington MA; R.W. Brachman
Duration: 1999 - 2006
Students: A. Dhar (PhD , 2002), S. Munro (MSc, 2006)
- Use of Type IV bedding for reinforced concrete pipes
Outline: The use of uncompacted native fill to backfill reinforced concrete pipes was investigated through field tests and finite element analysis
Collaborator: E.N. Allouche
Funding: Ontario Concrete Pipe Association, NSERC Discovery Grant
Duration: 2001 - 2002
Student: S. Wong (MESc, 2002)
- Analysis and Design of Loadout Tunnels Under Ore Stockpiles
Outline: Bulk solids are often removed from ore stockpiles using flexible metal or rigid concrete loadout tunnels. The design of the tunnels and the bulk-solids flow requires an assessment of earth pressures in and under the stockpiles. Finite element studies are being used to understand earth pressures during and after initial filling, unloading and refilling.
Collaborators: A. Roberts, and W. McBride, University of Newcastle (Australia)
Funding: NSERC Discovery Grant
Duration: 2000 -
Student: H.-Y. Jeong (PhD, 2005)
- Response of Silo Structures under Bulk Solid Loading.
Outline: Work has been conducted to compute the loads on silos when filled with bulk solids, assess the buckling strength under the action of vertical shear loads (taking into consideration the stabilizing effects of the bulk solid), and determine the shell response resulting from non-uniform solid-shell friction properties.
Funding: NSERC Collaborative Research Grant
Collaborators : J.M. Rotter and J.Y. Ooi, University of Edinburgh
Duration: 1994 - 1998
Students: J. Zhou (MESc, 1999) and M.T. Abdel-Fattah (PhD, 2001)
- Clogging of Drainage Systems for Municipal Solid Waste Landfills.
Outline: Work has been conducted to assess the impact of using large size gravel and large size perforations with plain HDPE leachate collection pipes to minimize biologically induced clogging. Testing and analysis was used to assess influence on local stresses in the HDPE pipe.
Funding: NSERC Collaborative Research Grant Collaborators : R.K. Rowe and others
Duration: 1994 - 2000
Students: R.W.I Brachman (PhD, 2000) and A.Tognon (MESc, 1999)
- Limit States Design of Large-Span Culverts
Outline: Analysis of field tests (conducted by Selig et al at UMass) was used to evaluate the effectiveness of 2D and 3D finite element analyses for calculating metal and concrete culvert response to earth and live loads. Design methods for the AASHTO Highway Bridge Design Code were developed using a parametric study conducted using the analyses.
Funding: NCHRP (US Academy of Sciences)
Collaborators : E.T. Selig at the University of Massachusetts, Amherst MA, and T.G. McGrath at Simpson, Gumpertz and Heger, Arlington MA
Duration: 1996 - 1999
Student: B. Taleb (PhD)