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With a single day remaining before the expression of
interest initation issued by the Ethiopian Roads
Authority (ERA) closed on February 15, only two
bidders bought tender documents for the construction
of an alternative river overpass for the Awash
Bridge.
The only link to the Port of Djibouti along the
paved road located to the east of the capital where
most of the country’s imports and exports pass, bore
the load of a huge transformer four times heavier
than its capacity three weeks ago.
According to Samson Wondimu, public relations head
at ERA, it has been decided that bridges that are on
the main trunk roads of the country should have
contingency routes.
“The back-up planned for Awash Bridge is part of
this decision,” he told Fortune.
The Authority publicised the expression of interest
for the rehabilitation of the existing Awash River
Bridge and design and construction of a new
alternative bridge on January 4, 2008. The notice
published in The Ethiopian Herald states that
the expression of interest must be delivered to the
Authority at or before February 18, 2008, 10:30PM.
“I do not anticipate that other companies would come
to buy the tender documents anymore,” a road
construction engineer told Fortune. “I expect
the Authority to extend the deadline.”
Located 227Km east of Addis Abeba, the 40-year-old
Awash Bridge has been used as the lone outlet of the
country to the Port of Djibouti and prior to that to
the Port of Assab in Eritrea. A transformer weighing
213tns recently crossed the 136m bridge, which has a
carrying capacity of only 50tns.
The transformer was needed for the Gilgel Gibe II
project, which the Ethiopian Electric Power
Corporation (EEPCo) has contracted to Salini
Custruttori SpA to undertake on the Gibe River, in
the Oromia Regional State.
The Spanish, CYMI-SOCOIN that EEPCo hired to
transport the first transformer has planned to move
another 217tns machine on this bridge soon for the
same project.
Although there were fears that the bridge would
rupture and eventually collapse, it only stretched
by 20mm, according to an assessment by Nigussie
Tebeje (emeritus professor).
The bridge is therefore expected contract back to
its original state.
According to a civil engineer, overload bridges
potentially face three types of deformations.
The first, affecting the plasticity index, causes a
brief but unnoticeable stretch and returns to the
normal position afterwards. A breach of the
elasticity index produces a noticeable inversion but
with a return to the previous state. The third and
worst scenario, according to the expert, occurs when
the yield limit is surpassed resulting in rupture
and no return to the original condition.
The civil engineer told Fortune he has heard
that the Awash Bridge expansion was an example of
violating the plasticity index.
“It is because we want to get ready in advance if
anything bad happens that we decided to construct an
alternative bridge,” Samson told Fortune.
ERA also has floated a tender to hire a consultant
engineer that supervises the construction of the
alternative bridge.
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