Expansion joint cover

Abstract

An expansion joint cover (10) broadly comprises a cover plate (38) to cover an expansion joint (12) between a first and second surface (14,16), an anchor assembly (40) to secure the plate (38) to the first surface (14), an insert (46) to protect the second surface (16), and one or more resilient bushings (48) to isolate the plate (38) from the anchor assembly (40). Under adverse conditions, such as during seismic events, the surfaces (14,16) may move significantly with respect to one another, thereby causing the plate (38) to slide over the second surface (16) and the insert (46) and deform the bushings (48). Thus, the flexibility of the plate (38), the durability of the insert (46), and the resilience of the bushings (48) all cooperate to allow the cover (10) to minimize stresses otherwise transferred to the anchor assembly (40).

Description

[0001] 1. Field of the Invention[0002] The present invention relates to expansion joints and expansion joint covers. More particularly, the present invention relates to an expansion joint cover that can be installed over an expansion joint between a first surface and a second surface.[0003] 2. Description of Prior Art[0004] Prior art expansion joint covers include cover plates covering expansion joints between first and second building surfaces. Typically, a first edge of the plate is coupled to the first surface and an opposed second edge is slidably received in a transition recess defined in the second surface. The second edge slides in the recess during relative movement of the surfaces caused by thermal expansion and contraction.[0005] The second surface typically presents a beveled recess wall where the recess meets an adjacent upper surface of the second surface. During a seismic event, the joint may narrow such that the second edge of the plate slides over the recess wall ont...

AI Technical Summary

Problems solved by technology

The recess wall is therefore subject to spalling, corrosion and potential impact damage from the second edge of the plate during a seismic event.

Additionally, stresses involved with the plate sliding onto the upper surface are typically transferred to bolts anchoring the plate, thereby inducing shock and shear forces capable of damaging the bolts.

Furthermore, since the plate and the bolts may be constructed of dissimilar metals, electrolysis may lead to galvanic corrosion of either the plate, the bolts, or both.

Additionally, the movement described above can be quite noisy.

As a result, installation on an existing building as a retrofit can be expensive and labor intensive.

Under adverse conditions, such as during seismic events, the building surfaces may move significantly with respect to one another.

In this case, the plate slides over the second surface, may flex and slide over the insert, and may deform the bushings.

Such stresses may otherwise shear the bolts, cause damage to the surfaces, or both.

Such misalignment may occur during construction of the building, installation of the cover, or during the cover's service life.

Without the bushings, the misalignment would otherwise induce stress on the anchor assembly leading to the damage described above.

Since the plate and the bolts may be constructed of dissimilar metals, electrolysis may otherwise lead to galvanic corrosion of either the plate, the bolts, or both.

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