here - Hyder Consulting

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here - Hyder Consulting

A TALE TWO

BRIDGES

BY CHAUNCEY HOLLINGSWORTH

PHOTOS BY MARTIN BEDDALL

Phil Tindall,

Hyder Consulting,

London, England


OFA PROJECT

TEAM REPLACES TWO

OUTDATED BRIDGES—

AND A TRADITIONAL

CONSTRUCTION

METHODOLOGY IN

THE PROCESS.


London’s traffic is legendary. Take the

A40. Running west through the center

of the English capital, the roadway

handles more than 100,000 vehicles a

day. It also traverses some of the city’s

busiest rail networks. But two of the

A40 bridges dating back to the 1920s

were in serious disrepair and in dire

need of attention.

Transport for London, the government

body responsible for most aspects

of the city’s transport system, realized

the bridges had to be replaced. It just

had to figure out how to pull off the

project—without disrupting all that

traffic or the neighbors.

Hyder Consulting, which won the

bid for the approximately four-year,

£16 million project, knew it was in for

some serious logistical snarls.

“One of the biggest challenges was

the railway,” says Phil Tindall, the

London-based U.K. technical director

for bridges at Hyder.

Together the rail lines handle more

than 800 trains, transporting 145,000

passengers daily.

The first bridge, which goes over the

North London Line, has trains running

18 hours a day.

That one didn’t seem overly daunting.

“Without too much difficulty, you

can get five to six hours on the nights or

>970 tonnes

The weight of the steel girders

used in constructing the bridges—

the weight of 130 London buses

the weekends to work over the railway

lines,” says Mr. Tindall, who started out

as project manager for the job and was

later promoted to project director. “You

could get an extended blockade of the

railway line and close it for a whole

weekend if you had to.”

But the second bridge was another

matter altogether.

Crossing the main rail lines that

come out of Paddington Station—

including the Heathrow Express, serving

the city’s busy airport—the bridge is in

use almost 24/7. At the project’s inception

in October of 2005, the bridge was

functioning 21 hours a day, 363 days a

year. Now it runs every day.

“Doing everything over such a busy

railway line involves working in possession

periods of three hours or negotiating

with the owners of Heathrow Express to

close the line for a period,” says Mr.

Tindall. “They wouldn’t agree to it very

easily or without payment of a very

large sum of money to enable them to

put people on buses with advance

publicity and recoup loss of profits.”

Under more forgiving circumstances,

the bridges would have simply

been torn down and replaced.

“The conventional wisdom for

something like this is you take a 48-

hour railroad possession, you build

something offline, demolish the old

bridge and get it there in one go,” he

says. “But that was looking like it was

going to cost far too much money and

be far too difficult.”

Two other factors foiled the drop-in

approach: a lack of nearby land where

new bridges could be built and

the extraordinary amount of utility

equipment running through

the decades-old structures.

“There are gas mains, electricity

mains—11,000 volts,

fairly high-voltage electric—and

masses and masses of fiber optic

cables that are feeding places

including the BBC’s main studios,”

Mr. Tindall says. “So

you’ve got to find somewhere to

put all that utility equipment first,

which would mean a double diversion

of utility equipment. You’d have to put

it onto a temporary bridge while you

put the new bridge in, then transfer the

equipment to the new bridge. That was

going to cost an absolute fortune.”

48 PM NETWORK SEPTEMBER 2009 WWW.PMI.ORG


HIGH STAKES

As if dealing with all the infrastructure logistics wasn’t enough, Hyder

Consulting also was up against an array of powerful stakeholders. To

secure buy-in from the very beginning, the company relied on in-depth

workshops with key stakeholders, largely highway operating and rail

authorities.

THE FORMAT

“The workshops are done around a value-management exercise so that

we’re exploring alternative ways of doing things,” says Phil Tindall, Hyder

Consulting.

THE RATIONALE

“Rather than everything being a fait accompli, we can involve the stakeholders

in some of the decision-making,” Mr. Tindall says. “Even though

the basic methodology is already there in outline, it’s still important to

allow for modification or change if something happens in the workshop.”

THE PREPARATION

Before starting the workshops, Hyder Consulting discussed its objectives

with a professional facilitator, who helped pull in the right people from

each of the major organizations.

“We want to make sure we have people who are senior enough that

they can make decisions,” Mr. Tindall says. “We want to make sure they

don’t have to go back to their organizations and be overruled.”

THE EXECUTION

The facilitator then touches base with stakeholders to cover main points in

the agenda and seeds thoughts about the issues they might want to discuss.

“The quality of the facilitator and the amount of pre-work he or she

does is as important as what happens on the day of the workshop,” Mr.

Tindall says. “If you don’t have that stuff ahead of time, what happens at

the workshop is not as effective.”

Clearly, conventional wisdom wouldn’t

apply for this project.

OUT OF SEQUENCE

Confronted with a host of options it

couldn’t use, the team faced the roadblock

with a simple premise: What can

we do?

One option was to use the available

space to build a couple of lanes’

worth of traffic alongside the existing

bridges, Mr. Tindall says.

“Using that as a principle, we

worked out a sequence in which we

could move the utilities and move the

traffic around through all the

different phases,” he says.

The team eventually arrived at a

solution by giving sequence the same

weight as design.

“There are so many jobs where the

consultant will do the design or the

permanent works, and the contractor

has to figure out what the construction

sequence is. ‘How am I going to build

it?’” Mr. Tindall says. “For this project,

everything was worked around the

sequence.”

Breaking with convention, the team

completed the demolition and construction

in multiple longitudinal slices

along each bridge.

“That was something that was new

to us,” Mr. Tindall says. “Working in

>

100,000

Number of

vehicles that use

the A40 per day

SEPTEMBER 2009 PM NETWORK 49


How did I handle the

stakeholders? “Patiently”

is the word. You do a lot

of talking, and very early

on in the project, we

held a series of valuemanagement

workshops

that involved some of

the key stakeholders—

the highway operating

and rail authorities, the

real major players.

—Phil Tindall

London—replacing bridges over railway

lines and dealing with all these utilities—

we’d done that quite a bit before. Our

advantage was experience and doing

things in more conventional ways—and

knowing ahead of time what works and

doesn’t work, and where the risks lie

and what you can do to mitigate those

risks. But the particular constraints of

this bridge drove the construction

methodology and sequencing.”

As with many projects, the devil was

in the details.

The team had to look at every aspect

of the construction in light of the piecemeal

nature of the project. All of the

steel beams were sized and arranged to

suit the amount of space available and

the variances demanded by the planned

sequence of sectional replacement.

The reinforcement of the bridges’

concrete decks was also designed to suit

the construction sequence. Steel formwork

was used on top of the steel beams

so the bridge decks could be layered in

concrete while trains ran underneath.

“With a lot of steel formwork systems,

you get gaps that are less than a quarter of

an inch [one-sixth of a centimeter] wide.

So when you form the concrete, you’ll

get water and cement paste dripping

through there,” Mr. Tindall says.

“Because the railway lines are underneath

and it’s high-voltage electrical,

you can’t afford to have wet concrete

50 PM NETWORK SEPTEMBER 2009 WWW.PMI.ORG


dripping onto those overhead lines

because there’s a possibility of electrical

shorting. Also, the cement paste goes

onto the wires, so when the connector of

the train comes along, it hits the cement

paste and wears things very badly.”

SPEAK UP

In many ways, working around the

A40’s constant flow of cars and trains

was a matter of simple traffic direction.

The larger issue was dealing

with the project’s panoply of powerful

stakeholders, including the transport

authorities as well as the British

public.

“How did I handle the stakeholders?”

Mr. Tindall asks. “‘Patiently’ is the

word. You do a lot of talking, and very

early on in the project, we held a series

of value-management workshops that

involved some of the key stakeholders—

the highway operating and rail

authorities, the real major players.”

Hyder used the meetings to present

its concept and then listened to the

stakeholders’ issues and discussed ideas

and solutions.

“We got everybody to work together

to buy into it, and that was very important

in terms of getting a way forward,”

Mr. Tindall says. “Then, for the other

parties who weren’t quite so crucial, we

did a lot of liaisons, a lot of talking and

a lot of meetings. You’d agree on things,

and they’d go away and come back with

something else. We went through a

whole series of iterations to get there in

the end.”

“The result of the feedback was

factored into the proposals where possible

to ensure that the design met the

needs of the customers,” says Chad

Frankish, portfolio manager at Transport

for London and project manager on the

A40 project for its last two years.

The project team decided to review

the pedestrian crossing proposals, for

example, after receiving the community’s

feedback.

To keep locals in the loop, the team

made visits to neighborhood schools,

sent out a quarterly newsletter and set

up a telephone helpline.

The team also tried to minimize the

impact on commuters as well as the

neighborhood and its residents, doing

as much work as possible during the

daytime when cars and trains were on

the move. But for safety reasons, some

tasks—such as the swap-out of concrete

sections—were performed during the

three-hour increments when the trains

weren’t running.

Pedestrian and cyclist access was also

maintained throughout the project.

Looking to keep a low carbon footprint,

the team set a target of achieving

a 5 percent reduction in CO2 emissions

and waste sent to landfills, and developed

an extensive landscaping plan for

the area around the bridges.

The efforts earned the team a silver

2009 national award from the Considerate

Constructors Scheme (CCS), a British

organization set up by the construction

industry to recognize best practices

beyond statutory requirements.

“Transport for London requires all

of its contractors to sign up to and

abide by the CCS code of conduct,”

says Mr. Frankish. “On the A40 project

in particular, strict adherence to the

CCS resulted in minimal complaints

and those received are actioned immediately.

By good teamwork, a proactive

public relations strategy and a united

project management approach, the

project management team has been

able to exceed the required standards.”

END OF THE LINE

With the exception of some finishing

and landscape work, the team is on

track to wrap up work this month.

Over the project’s four years, the

team suffered no major accidents and

even managed to integrate some

upgrades, such as creating access and

crossing improvements for pedestrians,

cyclists and people with disabilities.

And that legendary London traffic is

moving smoothly—above and below

the bridges. PM

>

145,000

Number of

passengers on

the 800 trains that

travel underneath

the A40 bridges

every day

SEPTEMBER 2009 PM NETWORK 51


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