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

UHPC machine beds, frames and foundation for a high-tech machines

Various UHPC binder systems have been used by us for more than 25 years worldwide for different
industries such as cement plants, power plants, iron, steel and mining industries. Developed and produced as wear protection and industrial flooring or as foundations and anchoring systems for the offshore and engineering industries.

UHPC concretes are very suitable for machine beds and frames of any kind of high-precision drilling machines, grinding and milling machines.

The advantages
A very high surface quality. Due to the accuracy of the moulds, subsequent machining can often be dispensed with. With UHPC, an accuracy of 0.1 mm/0.004 in from the mould can be achieved when using suitable moulds. The accuracy can be increased to 0.005 mm/0.0002 in by grinding.
Very high pressure resistance
Very good stiffness and dimensional stability

Very good damping properties compared to cast steel constructions and same vibration damping as natural stone. The vibration damping of UHPC concretes is approx. 70 - 80% faster than standard cast steel constructions. Higher precision with faster processing speed.

Thermal properties:
Applicable up to 450°C/840°F without loss of engineering properties and dimensional stability.
High thermal shock resistance
Inertia during heat transfer
Low thermal expansion
Non-flammable

Very good flowability.
High integration capability. All types and sizes of anchors, pins, threaded sleeves, structural steel elements
and pipes can be cast without problems.
Extreme adhesion to cast-in fasteners and anchor elements.
Very high corrosion resistance
Due to the high strength development, material thicknesses and material weights can be calculated significantly lower.
UHPC castings can be removed from the mould within 24 hours and reach more than 70% of their final strength after 48 hours.
Faster delivery times
Drastically reduced costs
Elements made of UHPC can be recycled and reused like normal construction waste.
Due to the low energy consumption and low CO2 impact, the production is much more environmentally friendly than cast, steel and reactive resin concrete.


Technical data for UHPC Cast products

Density 2400 - 2900 kg/m3 / 168 - 181 lb/ft3
Compressive strength after 2 days 100 - 120 MPa / 14500 - 17500 psi
Compressive strength after 28 days 140 - 250 MPa / 20300 - 36200 psi
Flexural strength 17 - 29 MPa / 2755 - 4200 psi
Max. Process temperature 450°C / 840°F


Applications
UHPC is suitable
for foundations, beds and frame parts of highly dynamic machine tools
for foundations of highly loaded machines, e.g. engines, generators, turbines, etc.
for foundations in the paper, wood, printing and textile industries

WPE DK International

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

 

UHPC concrete and residential housing construction - infinitely new possibilities

HPC and UHPC materials open up completely new worlds for architects, designers construction companies.

What is the difference between UHPC and standard concrete or natural stone?

The material  

HPC and UHPC binder systems are based on a very low cement content. All HPC and UHPC materials
are fully recyclable and have a service life of 100+ years. It is possible to mix HPC and UHPC binder systems with recycled aggregate. With HPC and UHPC binder systems, up to 50% construction material including reinforcement can be saved due to the high strength values.

The processing
HPC and UHPC materials can be easily processed as mortar, castable or Shotcrete material. The w/c ratio for our HPC and UHPC materials is between 0.22 and 0.17. There are no additives necessary. Pre-cast elements of all sizes and geometries can be produced in exactly the same way as large quantities of elements.

The design
HPC and UHPC surfaces and structures can be made extremely fine. This makes it possible to replicate almost all surfaces that occur in nature exactly. Whether in large or extremely fine size. HPC and UHPC can be combined with all kind of minerals, metals, plastics, pigments, woods, glasses, etc.

The resistance
HPC and UHPC is absolutely waterproof after just less than a 1/2 inch of layer thickness. HPC and UHPC is extremely corrosion-resistant, wear-resistant and easily resists all kind of animal attacks.

The properties
HPC and UHPC has a much higher compressive strength than very good concrete qualities. HPC and UHPC is very flowable and self-compacting in its casting version. HPC and UHPC concrete achieves its maximum strength within less than 48 hours.

The heat resistance
HPC and UHPC in its standard version can withstand temperatures up to 450°C/842°F permanently.
UHPC in its high temperature version can withstand temperatures up to over 1000°C/1832°F permanently. A normal fire, wildfire and bushfire even over a longer period of time can not damage a UHPC construction.

The facade
Vertical and horizontal gardens can be created with HPC and UHPC facades and roof structures. The HPC and UHPC specially produced for these applications is very light, is rot-resistant, waterproof, and plant roots cannot penetrate it. It can be laid seamlessly on a flat roof. For vertical (facade) gardens, combination constructions according to the design of architects or garden designers can easily be made in any size.

The insulation
UHPC can be combined with a variety of modern high performance insulation materials. With these
combinations, it is possible even at extreme outdoor temperatures without great expenditure of
energy to achieve pleasant internal temperatures easily. UHPC in this combination is extremely high energy efficient. 

 

The lightweight HPC and UHPC binder
We have developed lightweight HPC and UHPC mortars, castable and sprayable concretes that offer up to 50% weight savings compared to standard concrete.

The security
UHPC in a certain combination of materials is extremely well burglary resistant.

 Areas where UHPC offers great advantages

• Pool decks

  

• Curbs

• Steps

• Wall 

• Concrete ramps

• Swale

• Drive ways

• Footings, foundation, slabs

• Pads, additions, floors

 

UHPC - Standard concrete comparison

Standard concrete
A mixture of cement binder + sand + gravel + water

UHPC concrete
A mixture of UHPC binder + sand + water

One of the most important quality parameters
when comparing standard concrete and UHPC

Standard Cement Binder                         UHPC Binder         

is water/cement ratio and compressive strength.

The water/cement ratio is the ratio of the weight of water to the weight of cement used in a concrete mix.
A lower ratio leads to higher strength and durability, water/cement ratios of 0.4 to 0.5
are more typically used for standard concrete qualities. For higher-strength concrete, ratios of 0.20 - 0.18 are used.

Despite the extremely low w/c value, UHPC materials of high production quality 

can be processed in much the same way as 

concrete.

Among other things, the low w/c value
means that the pore volume is extremely low
or even absent, which leads to very high
compressive strength (up to 240 MPa) and
very high corrosion resistance. UHPC is also
self compacting.

Another effect of the low pore volume in UHPC
is the extremely high content of wetted surface,
e.g. on steel reinforcements against concrete.
This leads to very strong connection of steel
and UHPC. If you wanted to pull a standard
reinforcing steel out of a UHPC block you
needed enormous tensile forces compared to
a standard concrete reinforcement.

Due to the extremely low pore volume and the

high pressure and tensile strength combined
with the exclusive use of sand as aggregate, the coverage of the reinforcement can be reduced. Likewise, the distance between the reinforcing bars could be reduced.

In this context, UHPC can be used to make
concrete structures that are closer to steel structures than the ones in their dimensions
and bearing capacities.

 

 

 

 

 

 

 

 

WPE DK International

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