Education

At a cement manufacturing plant in Leamington Utah, two large reinforced concrete clinker silos were observed to be experiencing continued tilting, excessive cracking, and ovalling at their tops. A geotechnical investigation revealed significant variability in the soil conditions surrounding the silos. I was employed to determine the non-uniform support conditions that would lead to the deformations measured on site. The corresponding stresses in the concrete and the steel, as well as the long term implications to the operation of the facility were also examined. I used Abaqus, a finite element program with a non-linear reinforced concrete model, to investigate the condition of the two clinker silos. The analysis explained the observed deformations and demonstrated the need for substantial repairs.

Ontario Hydro had shut down one of the sixteen units at their hydroelectric generation station in Cornwall because of turbine operational problems. A survey revealed that the 33¢ diameter turbine shaft was 0.16² out-of-round. Along with a colleague, I made several trips to Cornwall to determine the in-situ steel stress of selected reinforcing steel bars in the disabled unit. Data collected was instrumental in helping Ontario Hydro decide on the action necessary to alleviate this problem. As well, weldable strain gauges were installed on numerous reinforcing steel bars for long-term monitoring.

Prince Rupert Grain Project : May 1991 - August 1991, February 1992 - March 1992

Prince Rupert Grain Limited observed excessive vertical cracking in their 60 large reinforced concrete storage silos. Cyclic loading of the silos was considered responsible for the increasing widths of the vertical cracks. To verify this suspicion, I conducted an experimental program which involved the construction and cyclic testing of two full-scale segments of the silo wall. A repair for this structure was proposed and then tested. This proposal was accepted and implemented. The structure now performs well.

A grid of three wall beams that span over the main ballroom and support upper floors showed signs of distress. A large internal steel truss was installed to help support the weight of the upper floors above the ballroom. I was involved in assessing the structural condition of the wall beams, and responsible for taking the field measurements necessary to ensure that the steel truss supported its intended share of the load (1300 tons). This involved making and interpreting crack surveys, measuring in-situ reinforcing bar strains, as well as the instrumentation and monitoring of the strains and deformations of the steel truss, existing wall beams, and the 28 Dywidag bars that were used to transfer the load from the wall beams to the truss.

Leamington Clinker Silo Investigation - Part II : December 1991 - February 1992

The operator of the facility desired to strengthen the clinker silos to prevent further damage to these structures. I performed another non-linear finite element analysis which concluded that a proposed 13' deep footings would adequately strengthen the structures. The footing was built and the structure now performs well.

On August 23, 1991, the Sleipner A Offshore Platform sank and imploded in a Norwegian fjord during deck mating, resulting in a one billion dollar loss. A crash program was undertaken to design and construct a replacement structure, Sleipner A2, in a record breaking 16 months. During construction, a potential problem was discovered that could once again lead to disaster during deck mating. To address this concern, three 1/2 scale models of the lower cell wall were tested at the University of Toronto. Under the direction of Michael Collins, I was responsible for all aspects of this program. In late November, 1992, 14 engineers, representing the owners (Exxon and Statoil), the designers, and the contractors, came to witness two of these experiments. Based on these tests and subsequent finite element analyses, it was concluded that the structure would be safe during deck mating. On April 30, 1993, successful deck mating of the Sleipner A2 Offshore Platform was achieved.

of Japan was developing their own non-linear finite element program to help in the design of a nuclear power plant for Tokyo Electric Power Corporation. To develop appropriate constitutive relationships to use in their program, they sent a researcher from Shimizu Corporation to the University of Toronto to conduct experimental work in our Shell Element Tester. This researcher and I worked together to construct, test, and analyze several large-scale elements.

Brent Bravo is an offshore structure in the Brent Oilfield. It was approaching its 20 year design life, but it was desired to continue to operate the structure for up to an additional 20 years. Due to potential problems in the existing internal plumbing system, the structure could be subjected to a larger net external pressure differential than that for which it was originally designed. I was responsible for the development, cost estimate, scheduling, and completion of a $US 130,000 research project with Exxon Production Research to determine the strength of the cell wall - upper dome connection. This work included hiring additional personnel, purchase of data acquisition and hydraulic equipment, modifications to our shell element testing rig as well as the construction, testing, and analysis of three complex test specimens.

A 300’ high open frame structure that in used to support calcinizers was showing some signs of distress. A survey of existing cracks was taken to access the condition of the structure. Instrumentation was installed to measure the change in temperature and deformation of major structural components. This information was analyzed to determine the influence of imposed deformation due to thermal forces, and the deterioration of the structure.

	Leamington Clinker Silo Investigation - Part I	May 1990 - October 1990
	R.H. Saunders Generation Station	November 1990 - March 1991
	Prince Rupert Grain Project	May 1991 - August 1991, February 1992 - March 1992
	Toronto Airport Hilton Investigation	August 1991 - November 1991
	Leamington Clinker Silo Investigation - Part II	December 1991 - February 1992
	Sleipner A2 Project	September 1992 - February 1993
	Tokyo Electric Power Corporation	May 1993 - August 1993
	Brent Bravo Project	August 1993 - February 1994
	St. Mary’s Cement Project	November 1996 – June 1997