Bus Ramp and Roads Do You Know?

# There are lots of things all around us

# Exciting things that surround us

-CHILDREN:

-# But how does it work?

-Do you know?

-# How is it made?

-Do you know?

# Things that go up Things that go down

# Things that go pop Things that go round

# With special cameras to show you inside

# It's going to be a big surprise

-# But how does it work?

-Do you know?

-# How is it made?

-Do you know?

-# Do you know?

-Let's find out! #

Hello, I'm Maddie. Today I'm going to meet my friend Lauren.

We're travelling on a bus.

There are lots of people out and about.

Some are walking their dogs.

Other people are travelling in cars, on bicycles and, of course, buses.

-Hi!

-Hi.

-Lauren, do you like to use buses?

I love using buses. I use them a lot.

And talking of which, there's a bus now!

Hello!

Have you noticed a special part of the bus that helps people to get on

if they're using a wheelchair, or if they can't step up too high?

Can you see that the bus is crouching down?

ALARM WAILS And listen for that sound.

The alarm tells us that

something special is about to happen...and look.

What's that coming out the side of the bus?

This is a bus ramp

and it means that Lauren can get on the bus really easily.

But do you know how a bus ramp works?

Let's find out.

I've come to this factory, where they make bus ramps.

Here, they make almost 2,000 bus ramps every year,

for buses all over the world.

Here's what the ramp looks like before it goes into a bus.

Let's take a closer look.

Underneath the bus, next to the wheels, are airbags called bellows.

They're full of air and keep the bus level.

When the driver presses a button inside the bus,

an electric signal goes to the bellows to tell them

to let some air out.

As the air comes out, the bus gets lower on one side.

It's a bit like letting the air out of a rubber ring.

When the bus is level with the pavement,

the driver presses another button to make the ramp come out.

Under the doors, there's a hidden box.

Inside the box is a bar fixed to the ramp.

When the driver presses the button,

the bar moves forward and pushes the ramp out.

When the ramp rests on the pavement, it's ready to be used.

And then, the ramp goes away,

the bellows fill back up and the bus drives off.

HONK! HONK!

The bus has been brought here so we can get a good look underneath it.

You should never go or play under a vehicle,

but we've got permission to be here,

so we can put my special camera under the bus

to get a closer look at the bellows.

I can see what's going on in the special camera

by looking at the screen on my phone.

Over to you, driver!

Watch the bellows here get squished as the air comes out.

Can you see a big black shape coming down?

That's the bus lowering, and it's squishing the bellows.

Let's see it again.

AIR HISSES Whoa! Listen to the hiss!

That's the sound of the air coming out of the bellows.

It sounds like a snake!

And now the bus has been lowered, the ramp is ready to come out.

How clever is that?

And when the person is finished using the ramp,

the driver presses a button and it goes back to how it started -

the ramp goes in and the bus is lifted back up by the bellows.

Just think, that bus weighs about 12 tonnes.

That's about the same as four elephants.

ELEPHANTS TRUMPET

The bellows have to be pretty strong to lift all of that!

I loved seeing how the bus was lowered and the ramp worked.

What was your favourite bit?

Do you remember what you call the airbags underneath the bus

which make it go up and down?

That's right, they're called bellows.

Did you hear the sound the bellows made as the air came out?

AIR HISSES

It made a hiss, like a snake.

And did you see the way the ramp came out

from a hidden box under the doors?

So, the next time you see someone using a bus ramp,

you'll know just how it works.

Look around. What can you see that all the buses and cars

are using to get around?

That's right, it's a road.

Roads are everywhere.

There's probably a road by your house or flat,

and if you go in a car or a bus, you'll go on a road.

You might use a road to go to the shops, or to school,

or maybe your friend's house.

But do you know how a road is made?

Let's find out!

The workers here are building a new road called a motorway.

Motorways are really big roads,

and lots of cars and lorries travel on them.

Have you been on a motorway?

You should never play on a building site,

but we've been given special permission

to see how a road is made.

First, a big digger arrives.

It's called an excavator.

And it works to dig up the soft ground

ready for the road to be laid.

Just look how much soil they're digging up!

And can you hear it creaking as it scoops up the dirt,

lifts it high in the air

and then dumps it in the back of the bulldozer?

After a lot of digging,

the workers are ready to start building the road.

First, a big truck arrives and delivers gravel.

Now, that is a lot of gravel!

I love the way the truck tips it all the way up in the air.

I've got some gravel here.

It's made of lots of little stones.

The workers need to spread it all over the area

where the road is going to be made.

Do you know how they're going to do it?

They use a bulldozer to spread out the gravel

and make it nice and flat.

The bulldozer is big, isn't it?

Can you see this big metal flat piece at the front?

Well, that's called the blade, and it's pushing the gravel around,

creating a large flat area, ready for the road-building to start.

It's definitely noisy!

Now the gravel has been laid out,

this big machine, called a roller, is going over it.

Listen to the sound the roller makes as it rumbles and rattles along.

ROLLER RUMBLES AND RATTLES

It's so powerful that it's making the ground shake!

The roller is pressing the gravel down and squishing it all together

so that it becomes hard.

And this becomes the base layer of the road.

It's called the formation, and then when that's done,

the workers lay a second layer of gravel,

and that's called the sublayer.

The sublayer is made from smaller pieces of gravel,

and it's spread out over the bigger gravel layer

and then pressed with the roller again.

The more the layers are pressed together,

the stronger the road will be.

And can you see that there are still little gaps between the gravel?

This means that rainwater will be able to drain away

so we don't end up with giant puddles on the motorway.

The next layer of the road is made of something called asphalt,

and the road workers lay it using this machine.

It's called a paver.

This is the front of the paver, where the asphalt is loaded.

Asphalt is made from bits of crushed rocks, sand and a black,

oily liquid called bitumen.

Bitumen is made from oil,

and it's what sticks the rocks and sand together.

It's also what makes the roads strong,

gives them their black colour.

This big lorry is loading the asphalt into the front of the paver.

Then it comes out of the back.

Can you see the steam coming off the asphalt?

That's because it's been heated up to make it super, super hot

so that they can pour it out of the paver and spread it around.

Now the asphalt has been spread out, it needs to be flattened down.

Can you guess what machine does that?

Yes, it's the roller.

But this roller is special,

because the wheel is sprayed with water

to stop the asphalt sticking to it.

Look at the steam as the water from the roller touches the asphalt.

That's because it's still really hot.

To show you just how hot the asphalt is,

I've got a special camera with me.

This is a thermal camera,

and it shows us how hot or cold things are using colour.

So anything that's cold will show up as blue or purple,

and anything that's warm or hot will show up as red or even white.

So let's see what colour the asphalt is.

Wow, OK. So if I point the thermal camera at people,

you can see that they're slightly blue or purple,

and that's because it's a chilly day. They're quite cold.

But if I point the thermal camera at the asphalt,

it looks golden.

It's showing up as white and yellow.

And that's because it's really, really hot.

That's really interesting.

So the roller, on the thermal imaging camera,

is leaving darker streaks in the white hot asphalt,

and that's because the water on the wheels is cooling it down

ever so slightly.

So to build a road, first the ground is dug up by an excavator.

Next, the bulldozer lays the gravel and it's rolled by a roller,

and then finally, the asphalt is laid by a paver.

It's looking good, isn't it? But it's not quite finished yet.

It has to be left to dry properly before anyone can use it.

After a few more layers of asphalt and it's been left to cool down

and go hard, we have a finished road!

And now it's ready for cars and lorries to drive on.

What was your favourite bit about seeing how a road was made?

Do you remember the name of the machine

that dug up the earth before the road was laid?

That's right, it's called an excavator.

Did you hear the sound the roller made when it squished

all the road layers together?

ROLLER RATTLES AND RUMBLES

And did you see how hot the asphalt was

when I used my special thermal camera?

So the next time you travel on a road, you'll know how it's made,

and you can think about all of the layers underneath.

And when you see or travel on a bus,

you now know how it lowers

and how the ramp goes in and out to let people on and off easily.

Right, that's my bus, so I've got to go.

I'll see you next time!

# There are lots of things all around us

# Exciting things that surround us

-# But how does it work?

-Do you know?

-# How is it made?

-Do you know?

-# Do you know?

-Let's find out! #