Journal of Performance of Constructed Facilities

A scheme for reviewing the condition of long-span corrugated metal culverts is outlined. The scheme assesses the significance of observed pipe deformations. The scheme has been used successfully in Elgin County, Ontario, to assess culvert performance and to assist in the management of repair and rehabilitation work. Specific measurements are given for 39 culverts with a range of spans, heights, and culvert shapes. Details are given of the culvert ranking, and the courses of action for structures judged to be in need of treatment.

The successful rehabilitation of three corrugated steel plate culverts consisting of 11.28-m-span horizontal ellipses is described. When constructed in 1970, the culverts were the longest-span horizontal ellipse culverts in the world. The original construction is described, with a summary of the discovery and site investigation. The nature of the structural distress and the identification of the cause is discussed. The design of an effective repair is described in addition to the requirements for construction monitoring. Measurements of culvert response are given for pipe excavation and subsequent reburial. Details of the rehabilitation process are provided with a discussion of the structural and backfill design. The total project cost is included.

A barrier to constructability is any significant inhibitor that prevents effective implementation of the constructability program. Barriers to successful implementation of constructability programs are present in almost all organizations at both corporate and project levels. Treatment of constructability barriers should involve a three-phase cycle: identification, mitigation, and review. Initial efforts should focus on determining the presence and relative significance of constructability barriers. Recognition of barriers to constructability has been identified as one of 15 significant parameters critical for effective constructability implementation. Once barriers to constructability are identified within an organization or a project team, they may be mitigated or overcome with certain tactics, known as “barrier breakers.” Such breakers should be both effective in combating the barriers and should be implementable or relatively easy to apply. This paper describes the development, evaluation, characterization, and application of barrier breakers for the seven most prevalent barriers to successful implementation of constructability efforts.

All the technical papers written about the April 23, 1987, collapse of L'Ambiance Plaza, Bridgeport, Conn., have treated it by static-analysis methods. It was established that a 12-ton jack was used just prior to the collapse to plumb the building; however, no one attempted to link the dynamic load generated by the force of the jack to the dynamic vulnerability of the lift-slab structures during the construction stage. This paper is an attempt to show that the dynamic vulnerability of the lift slab, combined with the dynamic load such as the one generated by the 12-ton jack, could have caused the dynamic instability of the structure, which led to the collapse.

This paper describes a failure of linoleum-tile floor covering placed on a concrete slab in a retail grocery facility. Moisture caused the failure, but different parties involved in the project postulated different sources of the moisture, and consequently, each party proposed a different assignment of blame for the failure. This paper reviews moisture movement in concrete slabs and compares the different explanations for the failure. Relationships among the different parties and the impact of these relationships on their postulated causes for failure are also examined. The most likely source of the moisture that caused the tile failure was an excessively thick sand protective layer placed on the vapor retarder. One portion of the floor slab had been left uncompleted. This exposed the sand to prolonged rain, which resulted in a reservoir of water trapped between the floor slab and vapor retarder.

This paper presents results from the experimental investigations of the dynamic characteristics conducted on a long-span bridge in the Vancouver area, the Queensborough Bridge. This bridge is a key component of Canada's Highway 91, which leads through a highly populated area of the Fraser Delta. A major subduction zone is located off the coast of British Columbia and represents a significant risk of a possible megathrust earthquake with magnitude in the range of 8.5–9.0. The four lanes of the Queenborough Bridge were built to cross the North Arm of the Fraser River in 1960. These tests were part of an ongoing seismic retrofit program and were conducted to evaluate the bridge's dynamic response using an efficient technique to determine its fundamental dynamic characteristics from ambient vibration measurements. Although some results matched the expected behavior quite closely, others yielded additional insight into the dynamic response of the bridge. The results of soil-structure interaction at different locations along the bridge, which showed a close relationship between the lateral and vertical modes of vibration, presented rather valuable information for the retrofit efforts.