Less
than six months after the Third Mainland Bridge underwent a major repair work,
a new report at the weekend revealed that about 1,318 foundation piles of the
bridge “have concrete degradation and appreciable loss of concrete materials”.
Even before the new report was issued
last month, THISDAY checks revealed that Lagos State Governor Babatunde Fashola
(SAN) had directed the state’s Commissioner for Transportation, Mr. Kayode
Opeifa to write the Federal Government on the grave conditions of the bridge despite
the recent repair work carried out on the infrastructure.
But the report, which was authored by
NSD Divers & Engineers in collaboration with Concrete Structural
Engineering Laboratory of the Yonsei University, South Korea, was issued after
an independent structural integrity test conducted on the bridge on December 3
and 4, 2012.
The report, which THISDAY exclusively
obtained, was commissioned by Senator Gbenga Ashafa (Lagos East), Senator
Oluremi Tinubu (Lagos Central) and Senator Ganiyu Solomon (Lagos West)
following experts’ complaints about the integrity of the bridge.
The report said underwater inspections
were conducted using the latest tools available in the industry; the residual
thickness of the caissons checked, integrity of the reinforced concrete in-fill
tested and corrosion of the embedded steel reinforcements investigated.
The report further added that the
scope of the inspection covered soil erosion and accretion at the pile or
lagoon bed interfaces, all of which showed grave conditions of concrete
degradation and concrete materials in about 1,318 piles.
Consequent upon the inspections just
conducted, the report noted that there “was concrete degradation and
appreciable loss of concrete material in 46 foundation piles. There was
extensive reinforcement bars deterioration in about 8 piles.
“There was extensive damage of
confining steel caissons and progressive concrete spalling in 24 piles. There
was also progressive caisson deterioration in 1,318 foundation piles,” the
report said along with pictorial evidence that shows the state of the bridge.
In a cover letter attached to the
report and addressed to the lawmakers, the report warned that the Third
Mainland Bridge “is an accident waiting to happen unless the degradations are
urgently arrested” to avert grave situations on Africa’s longest bridge.
Consequently, the report was the
rationale behind a motion which Ashafa co-sponsored with 55 other senators,
asking the Federal Government “to urgently conduct an investigation to
ascertain the true state of the Third Mainland Bridge in Lagos”.
In the motion, the lawmaker explained
that there had been incessant complaints of shifting and unusual vibrations on
the bridge by commuters plying the bridge for quite some time, even after the
Federal Government carried out repair works on the bridge.
He said a report produced by a company
“experienced in underwater surveys indicated that the underwater metal casing,
housing the concrete piles on which the bridge stands have rusted and this
accounts for the vibration experience in some portions of the bridge.
This led to the closure of the bridge
for repairs between July 7 and October 30, 2012”.
The lawmaker further noted that Professor JHT Kim, Head of The Concrete Structural Engineering Laboratory, Yousei University, Seoul Korea “came on research in December 2012 and conducted an underwater examination of the structures holding the bridge and reported that the damages to the structure was worse than what he had been briefed.”
The lawmaker further noted that Professor JHT Kim, Head of The Concrete Structural Engineering Laboratory, Yousei University, Seoul Korea “came on research in December 2012 and conducted an underwater examination of the structures holding the bridge and reported that the damages to the structure was worse than what he had been briefed.”
He said that such abandonment could
lead to the collapse of the bridge as was the case with the bridge over
Mississippi River at Minneapolis in the United States on August 1, 2007 and
Sungsu Bridge in seoul, South Korea on October 21, 1994 among others.
He therefore said the collapse of the
bridge could lead to a huge loss of lives and worsen the traffic situation in
Lagos, the commercial hub of Nigeria taking cognisance of an average
number of 70,000 vehicles that ply the bridge on daily according to the Lagos
State Ministry of Transportation.
The lawmaker urged the Federal
Government “to carry out inspections on all over-water bridges in Nigeria to
save them from further deterioration and collapse”.
Source:
Thisday
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