finishes bridge

8/16/2019 Finishes Bridge

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Finishes

1) Road Works

a) Parapet

Specification of the concrete parapet for bridge:-

- Their movement after impact is controlled.

- Reduces the deceleration eperienced b! the passengers "#plastic impact#).

- $ontrols the path of vehicle after impact.

- %oes not transfer the impact energ! to the bridge structures

b) Rain&ater %rainage

- The %esign 'anual for Roads and (ridges (% *+, reuires surface &ater to be

drained a&a! from earth retaining structures or backfill. This &ill normall! allo& the

retaining &all or abutment to be designed &ith /ero ground &ater pressure on the back of

the &all above the perforated drainage pipe level0 this leads to a considerable cost saving.

n instance &here h!drostatic pressures &ill need to be considered is &here there is a

possibilit! of a burst &ater main in the vacinit! of the &all.



n! &ater percolating through the fill is collected in a perforated drainpipe2 not less than

13*mm diameter2 &hich is located at the rear of the vertical stem of the &all at the level

of the top of the footing. ccess to the pipe should be provided for rodding purposes from

inspection manholes positioned at the foot of the &all. Weep holes are often provided as a

safeguard in the event that the drainpipe is blocked0 the! also provide a visual check that

the s!stem is &orking.

4nless the backfill to the &all is highl! permeable then a vertical drainage la!er is

provided at the rear of the &all and is connected &ith the perforated drainpipe.

The vertical permeable la!er sho&n in the diagram above consists of hollo& concrete



block&ork2 ho&ever it ma! also take the form of:

1. $ast in-situ porous no fines concrete

5. 6ranular drainage la!er.

There are also proprietar! s!stems on the market2 such as Terram 6eocomposite %rains2

but the! &ill need %fT approval to be used on a high&a! structure.

Special consideration to the drainage la!er is reuired &hen the backfill contains

materials susceptible to piping such as silt2 chalk or P7. 4nder these conditions then a

granular drainage la!er onl! is recommended0 hollo& blocks or no fines concrete are

unsuitable

c) Road 8erbs

- can be build b! road concrete curb machine

- is constructed at parking lots

- functions

i. separate the road from the roadside2

ii. discourage drivers from parking or driving on side&alks and la&ns.

iii. provide structural support to the pavement edge.

iv. used to channel runoff &ater from rain

d) sphalt Pavement

- sphalt paving

The first person in the paving team2 ho&ever2 is the truck driver &ho fills the asphalt into

the paver9s hopper. T&o mutuall! independent conve!ors transport the material through

the machine to the rear2 &here it is uniforml! distributed bet&een paver and screed b!

t&o individuall! controlled rotating scre& conve!ors. When paving a standard mi2 the

temperature should al&a!s remain above 11* $ in order to ensure sufficient time for

compaction.

The hot mi should be covered &hen delivered b! charging trucks to ensure that the

paving operation is carried out in the most suitable time frame. To guarantee continuous

paving2 the capacit! of the asphalt miing plant al&a!s needs to be higher than the

paver;s la!do&n capacit!. <f the paver stops moving due to lack of material2 disruptive

http://www.terram.com/market-sector/highways/





lateral =oints occur as a result of the paved la!er cooling do&n. When paving standard

mi2 the paving temperature should be higher than 11*$ to allo& an as large time frame

as possible for compaction.

ll paving units need to be heated prior to commencing the paving operation to prevent

the mi from sticking to sensitive parts of the machine. >n modern pavers2 the

compacting s!stems in the screed can be actuated separatel!. Particularl! the high

compaction screeds achieve ver! good compaction. s a result2 the rollers behind the

paver reuire fe&er passes to achieve the specified final degree of compaction.

$ompaction effected b! the high-densit! screed enables the rollers &hich follo& behind

the paver to achieve the overall final densit! specified b! the client in fe&er roller passes.

<n most cases2 the road paver is geared for either high densit! or fast advance speed2 both

of &hich have an effect on the number of roller passes reuired.

e) Roadmarking

- mark is paint bet&een the t&o lanes b! road marking machine.

5) '?@ Works

a) Aighting Pore

b) Wiring

c) Aighting S!stem

d) Road Sign

e) %istance Signboard

f) $$TB S!stem

g) @mergenc! Telephone

finishes bridge

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