UHPC pavement for extreme heat and extreme cold

 

Asphalt road surfaces have very big problems when there are extreme summers with long-lasting very
high temperatures. The asphalt loses its bearing capacity the higher the ambient temperatures become, it becomes soft. In extreme cases it sticks to vehicle wheels and shoes. Accidents can occur because there is no longer any adhesion to the surface. Likewise, in extreme cases, people can no longer walk on these surfaces or roads are closed because of the risk of accidents.

Standard concrete road surfaces have problems in extreme cold. Cracks in the concrete and salt spreading to keep the roads passable destroy the concrete including reinforcement in the long run. Water penetrates the concrete cracks, freezes to ice, expands and cracks the concrete. De-icing salt penetrates the concrete cracks, the reinforcement corrodes, expands and blasts the concrete from the reinforcement. 

 

We will always find these extreme situations in many parts of the world in the future. The cost of maintaining transport infrastructure is immeasurable. It is impossible under the present conditions for road and bridge maintenance to carry out all the necessary repairs. In addition to the lack of financial budgets, many places also lack the staff to carry out this work.

UHPC Phalt semi-rigid overlays could be a durable solution for such extreme temperatures. This solution
combines the flexibility of asphalt with the very high load-bearing capacity and wear resistance of UHPC concrete. The standard asphalt is modified in its structure and serves as a matrix for the very fluid UHPC concrete. The UHPC Phalt slurry penetrates the asphalt matrix via the open-pored structure and fills it completely. 

 

 

 

WPE DK International

Phone: 0049 176 601 73146
E-mail: info@wpe-dk.dk
Homepage: www.wpe-dk.com

 

We increase the sustainability of UHPC

With our high-performance UHPC products, we started

using sustainable products years ago. We are also

increasingly focusing on sustainability when it comes

to units for our UHPC binders.

One example is corundum, which we use as an aggregate,

among other things. Corundum can be produced as

synthetic corundum with very high energy consumption

or can be mined as natural corundum in open-cast mining.

We have chosen natural corundum for more than 15 years.

Together with our partner in Africa, we pay attention to a

nature-friendly mining and an equally nature-friendly

restoration of the surface areas. The natural corundum

mined by our partner has proven to be an almost perfect

unit for our UHPC over many hundreds of applications

in the offshore industry, architecture, wear protection

and security industry.

Another problematic aggregate of quartz sand, we can

completely replace today with desert sand, including

from Africa. The technical values ​​of desert sand

concrete are far above the best standard concrete.

In our opinion, it is not necessary to destroy beaches

and rivers by sand mining. The cost of desert sand

mining is many times less than the predatory mining

of river sand or beach sand.

As far as the reinforcement systems or fiber systems

are concerned, nature offers us very sustainable

products that can be used in combination with

high-quality UHPC binder systems to create a perfect

sustainable product.

Our goal is always to produce UHPC binder systems

so flexibly that we can always use a high proportion

of local raw materials.

WPE DK International

Phone: 0049 176 601 73146
E-mail: info@wpe-dk.dk
Homepage: www.wpe-dk.com

 

Test your UHPC Know How - Learning Module

This is one of our learning modules for UHPC Concrete. A new version will be released this year. We use such modules for training purposes. New ones are added every year. This year there will be four new modules. 

You want to check your answers for correctness? Send us an email service@hhbc-consulting.de with the password "LMS 1/6" and we will send you an answer sheet.

Module no. 1/6

What are the main components in UHPC?

1. Cement, microsilica, superplastisizer
2. Cement, flyash, superplastisizer
3. Epoxy, microsilica, dispersant
4. Cement, sand, epoxy
5. Cement, sand, microsilica

Acid will deteriorate UHPC

1. True
2. False
3. Only if pH is below 5
4. Only if pH is above 5
5. Only if pH is below 3

Alkali will deteriorate UHPC

1. True
2. False
3. Only if pH is above 12
4. Only if pH is below 12
5. Only if pH is above 13

The following aggregates are used in UHPC Standard wear protection?

1. Quarz
2. Bauxite
3. Corundum
4. Silicium carbide
5. Titanium carbide

The wear resistanse of UHPC increases with these aggregates?

1. Quarz, bauxite, corundum, silicium carbide
2. Bauxite, quarz, corundum, silicium carbide
3. Silicium carbide, bauxite, quarz, corundum
4. Bauxite, corundum, quarz, silicium carbide
5. Silicium carbide, corundum, bauxite, quarz

What is the lowest temperature at which it is ok to install UHPC?

1. 20°C / 68°F
2. 10°C / 50°F
3.   5°C / 41°F
4.   0°C / 32°F
5. - 5°C / 23°F

What do you need to protect UHPC against when installing it?

1. Drying out
2. Freezing
3. Wind
4. Direct sun
5. Rain

What should you focus on when mixing UHPC in regards to water?

1. The product cannot seggregate
2. The product must remain dry
3. There must be free water on top of the product in the mixer
4. You cannot add too much water to UHPC
5. Any mixing problem can be solved by adding more water

You notice lumps in a bag of UHPC Binder, what do you do?

1. No problem, I just add more water when mixing
2. I contact hhbc-consulting or to have a new bag
3. I control the storage environment
4. I discard the bag
5. I check the date on the bag to see age of product

When mixing UHPC lumps are formed shortly after adding of water?

1. No problem, I just add more water
2. I wait a while to see if they mix out, if not I will add a little more water
3. I throw away the mix
4. I check if the mixer is proper prepared for mixing UHPC
5. I increase the speed of the mixer

When mixing UHPC I notice free water on the surface of the mix?

1. No problem, Just need to use the product fast
2. I allow the mixer to run for longer time, untill the free water is no longer there
3. I will try to scoop out the free water
4. I throw away the mix
5. I add more powder untill the free water disappeares

What is the purpose of Microsilica in UHPC?

1. It is packing between cement particles, increasing density and displacing water
2. It is like little ball bearings making the mortar more flowable
3. It reacts with Ca(OH)2 from the cement hydration and create a denser material
4. It has no significant effect, just a filler to make the product cheaper
5. There is no microsilica in UHPC

What is the purpose of superplasticizer in UHPC?

1. It makes the product more flexible
2. It charges all particles so that they repell each other. At the same time it makes stearic hinderence so that particles cannot bridge build on each other, and in this way it displaces water.
3. There is no superplasticizer in UHPC
4. It is a polymer, added to make the product easier to mix
5. It is lubricating the particles so that they can react better

UHPC Binder can be installed over head?

1. True
2. False
3. Sometimes if you are lucky
4. Only during the weekend
5. Only if you use a special throwel

HT products can be used in temperature areas of

1. Up to 1200°C / 2192°F
2. Not above 1000°C / 1832°F
3. Not above 600°C / 1112°F
4. Not above 400°C / 752°F
5. Not above 200°C / 392°F

UHPC (not HT) can be used in temperature areas of

1. Up to 1200°C / 2192°F
2. Not above 1000°C / 1832°F
3. Not above 600°C / 1112°F
4. Not above 400°C / 752°F
5. Not above 200°C / 392°F

It is important to know what chemicals UHPC will be subjected to

1. True
2. False
3. Only acid or alkalies
4. Especially if there are salts present
5. Only if temperature is above 100 deg C

When mixing you notice the wetting time is increased. What do you do?

1. No problem, I just add more water
2. I wait it out for a while to see if it wets through, and I adjust the water accordingly
3. I throw away the mix
4. I ignore it
5. Cross my fingers and hope everything will be ok

What happens to UHPC if too much water is added?

1. Nothing, you can add as much water as you like
2. The product will most likely seggregate, but properties will in general be reduced in direct correlation with the amount of water added.
3. Especially if we are working with a UHPC Cast product, installation will be a lot easier
4. Strength will increase as we will hydrate more cement
5. The stickyness of the product will increase a lot

How does UHPC differ from cement/concrete?

1. It is the same, no difference
2. UHPC is stronger in terms of compressive strength
3. UHPC is more dense
4. Concrete is more flexible
5. UHPC can be installed under water

How does UHPC differ from refractory?

1. It i the same, no difference
2. Refractory needs heat to finalize its reactions, UHPC does not
3. UHPC is more wear resistant
4. The insulation properties of UHPC is better than that of refractory
5. UHPC can withstand higher temperatures compared to refractories
    
    
   WPE DK International
   
   Phone: 0049 176 601 73146
   E-mail: ber@wpe-dk.dk
   Homepage: www.wpe-dk.com