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The Restoration of Harvard Stadium

by Wayne R. Lawson, P.E., SECB, Principal

 

Harvard Stadium was originally constructed over a five (5) month period in 1903 at a cost of $310,000.  In 1910 the colonnade level columns, wall, and roof were added.  During the renovation in 1929, steel bleachers were installed at the northeast end making the stadium into an oval configuration and thereby increasing the seating capacity to 57,000.  However, in 1952, the bleachers were removed, reverting the stadium back to its original horseshoe shape with a total seating capacity of 37,000.  In 1982, at a cost of $8 million, a renovation was made including precast concrete seating, making the stadium into what we see today.

CBI Consulting Inc. was engaged by Harvard University to investigate methods and procedures to be used for maintenance repair of Harvard Stadium.  This investigation had several purposes:

a.   Correct some of the more serious areas of concrete spalling and deterioration while replicating the natural color cone of the adjacent concrete surfaces.

b.   Investigate concrete cracking and methods of repair.

c.   Evaluate through load testing the capacity of a typical in-situ concrete transfer beam.

Despite signs of deterioration and evidence of supplemental framing, CBI recognized that the stadium had been successfully utilized for over 100 years without signs of overstress or failure.  It was this historical performance that lead CBI to advise the owner that undertaking a field load test was an expenditure that, if successful, would derive significant cost saving to the overall stadium restoration project.

The interior concrete transfer beam at Seating Section 26 was selected for load testing based on the visual appearance of the beam (extensive cracks, and extreme efflorescence on the concrete surface), petrographic confirmation of ASR and unknown variables, which resulted in installation of two structural support members during the 1982 repairs.

A number of top surface loading methods were reviewed including mass concrete blocks and water, however these required disruption of the stadium activities.  By working with a rigging contractor, an underside loading method was devised, utilizing a crane counterweight load frame that was supported by six (6) 25-ton hydraulic jacks and suspended from the subject beam through a steel cable and harness.

The loading for the test was calculated in accordance with ACI Chapter 20.  CBI concluded that the initial rest load should be 90 kips to satisfy the current “as-built” conditions.  In the event that this loading was successfully supported by the beam, the test load would be raised to the 1903 framing conditions (190 kips) and if permissible ultimately to the shear capacity of the beam concrete (214 kips).

The load test results successfully demonstrated that the existing beams could safely support the required dead and live loads.  These results eliminated the need for installation of permanent supplemental framing, allowing more expenditures for other necessary stadium repairs and improvements. 

The restoration of Harvard Stadium illustrates the challenges that face the engineer.  The completion of a successful project requires an ability to evaluate and solve specific and often unique conditions throughout the design and the construction process.  These issues require engineering/technical knowledge and experience, with a clear understanding of the owner’s financial limitations.