STRUCTURE

Structure:

 The bridge consists of superstructure, substructure and spans.

Superstructure

The superstructure consists of the components that actually span the obstacle the bridge is intended to cross and includes the following:

1) Bridge deck

2) Structural members

3) Parapets (bridge railings), handrails, sidewalk, lighting and some drainage features

Substructure

The substructure consists of all of the parts that support the superstructure.

Span

A span is a segment of a bridge that crosses from one substructure unit to the next. This bridge consists of five spans.







Bridge Dimensions

The bridge itself is long and slightly tapered structure that gently curves across the river between the rich area of Canary Wharf and the relatively poor area of West India Quay. The main stipulation of the design competition was that no weight would be imposed onto the riversides or pavements. The winning design by Future Systems and Anthony Hunt Associates was a bridge that appeared to be “floating” on the river. The weight of the bridge is supported by six pontoons that are secured into the riverbed using light tension piles.

·          Slightly curved and tapering aluminium decking supported on four sets of tubular steel legs. 80m long.

·          They rest on mostly submerged pontoons which are held in place by light tension piles.

·          Supported by a set of X-shaped steel struts which are connected at an angle to a central spine beam.

·          Each set of x-shaped legs support two large pontoons, equalling 6 pontoons in total.

·          The splayed legs of the bridge are bolted to the central spine of the bridge; they end in conical shapes that are welded to the surface of the pontoons.

·          Only 500mm of the 2800mm pontoons are visible upon the water surface.  The remaining material of the pontoons are fixed to the river bed with steel piles.

·          The main tension of the weight of the bridge is held on the pontoons. Although it looks like the weight is distributed evenly across to the pavement – this is not correct. The structure of the bridge is only “resting” upon the surface of the said pavements.

Triangulated configurations work through axial loads only; sections are much lighter

Footpath:

Although the main decking of the bridge looks like one long curving structure it actually consists of three sections. Two curved edges that meet the pavement at both ends and one straight middle section. This split is to allow the hydraulic system to open the bridge in case of a passing boat. The handrails are supported within the decking and help protect the crossing pedestrians.

·          The decking section of the bridge is split into three sections. Two “curved” edges and one straight middle section. 

·          This middle section is 6600mm long and is part of a hydraulic system in order to allow the boats to pass through.

·          This hydraulic system works by a simple cantilever counterbalance which is controlled by the harbourmaster.

·          The decking itself is made from a 75mm deep aluminium box with a grooved pattern to create a non-slip surface for pedestrians

·          A balustrade of stainless steel cables connected with turnbuckles to steel T-shaped supports run the length of both sides of the bridge. These are supported within a steel frame on the floor.