e-mosty March 2019 Long Span and Multiple Span Bridges - Page 35

Figures 3 and 4: Location of the Bridge on the map Source: Google maps For hundreds of years the ferry route connected the City of Maputo with the opposite bank. The ferry services were operated by unseaworthy vessels or sometimes disrupted by cyclones. A permanent link to replace the ferries became the source of debate for a number of decades until 2014 when the crossing became real with the proposed bridge solving forever the above mentioned problems. With Pylons reaching up to a height of 143 metres the Suspension Bridge is without doubt an impressive landmark of the city Maputo, for Mozambique and for all Africa. The Bridge was under construction for approximately 3.5 years. The Bridge has been in use since the end of 2018 when it was handed over to the Mozambican Government. DESIGN AND CONSTRUCTION OF THE BRIDGE LAYOUT OF THE BRIDGE The total length of the whole crossing is 3,003m. The North Approach Bridge length is 1,093m, measured from the abutment to the Suspension Bridge North pylon. The South Approach Bridge length is 1,230m, measured from the abutment to the South pylon. The main Suspension Bridge, the longest in Africa, has a total length of 1,224m between the anchorages and comprising a central span of 680m. There is an overlap between the back spans of the suspension cables and the approach viaducts as shown in the layout. The North Approach Bridge is made up of two different bridge types. Measured from the abutment the 8 No. spans were constructed as a Precast Beam Bridge. The maximum span is 30m. It then continued with the construction of one of the most challenging bridge construction stages in the world, a Free Cantilever Bridge (FCB) with a total length of 853m and having a maximum span of 119m. At the beginning of this section viewed in plan, the FCB alignment is highly curved and has a 6% cross slope. It then straightens briefly before a reverse curve leading up to the Suspension Bridge section. Adjacent to this is the three span Suspension Bridge of which the spans are 260m + 680m + 284m = 1,224m. The South Approach Bridge comprises a Precast Beam Bridge. T-beam precast beams lengths vary from 45m to 30m. The total length is 3 x 45m + 3 x 45m + 3 x 45m + 5 x 30m + 5 x 30m + 5 x 30m + 4 x 30m + 4 x 30m = 1,230m. Close to the abutment the bridge is also on a curved alignment (see below). The South Approach Bridge was constructed conventionally with linked spans of Precast Beams with an in-situ deck, with movement joints every 3 to 5 spans. 1/2019