Flexible expansion joint seal

1. An expansion joint seal for a structure, the seal comprising:

a central portion including a sidewall comprising members, the sidewall configured to define at least one central chamber disposed around a centerline;

a first flange portion extending outwardly from the centerline; and

a second flange portion extending outwardly from the centerline in a direction opposite the first flange portion;

wherein at least one of the first flange portion and the second flange portion is bifurcated into an upper flange portion and a lower flange portion, the lower flange portion being substantially parallel to the upper flange portion, and the upper flange portion extending further in length from the centerline than the lower flange portion, the thickness of each of the upper flange portion and the lower flange portion being planar and substantially the same as the thickness of the members of the sidewall;

wherein when installed on the structure the first flange portion is attachable to a first substrate of the structure and the second flange portion is attachable to a second substrate of the structure such that the central portion is disposed within and seals a gap formed between the first substrate and the second substrate of the structure; and

wherein movement of one or both of the first substrate and the second substrate causes a response in the central portion to maintain the seal.

2. The joint seal of claim 1 , wherein at least one of the first flange portion and the second flange portion is comprised of a flexible materials such that the at least one of the first flange portion and the second flange portion may be affixed to the structure at an angle or an elevation that differs from the central portion.

3. The joint seal of claim 1 , further including a bracket disposed between the upper flange portion and the lower flange portion to facilitate mounting of the expansion joint seal to the structure.

4. The joint seal of claim 1 , wherein when installed the upper flange portion and the lower flange portion interlay with two or more layers of materials.

5. The joint seal of claim 1 , wherein expansion of at least one of the first substrate and second substrate causes the central portion to deflect upward such that the central portion does not impinge on itself or prevent movement of one or both of the first substrate and the second substrate while maintaining the seal.

6. The joint seal of claim 1 wherein contraction of at least one of the first substrate and the second substrate causes the central portion to deflect downward such that the central portion does not impinge on itself or prevent movement of one or both of the first substrate and the second substrate while maintaining the seal.

7. The joint seal of claim 1 wherein the central portion includes a sidewall, the sidewall configured to define the at least one central chamber, the at least one central chamber being configured to be selectively collapsible in response to a force from movement of one or both of the first substrate and the second substrate.

8. The joint seal of claim 7 wherein the at least one central chamber is comprised of at least one pair of central chambers disposed about the centerline.

9. The joint seal of claim 1 wherein the at least one central chamber is comprised of an odd number of central chambers.