Showing posts with label concretetechnology. Show all posts
Showing posts with label concretetechnology. Show all posts

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