New build and repair of sewage treatment plants and sewers with UHPC concrete

Sewage treatment plants and sewers are exposed
to a permanent chemical and mechanical attack
by sewage from households and industry. Due
to the changing climate conditions and the resulting
extreme rain or flood masses, the systems and
channels are extremely stressed and damage that
their function is no longer guaranteed.

A material with high resistance to chemical and
mechanical attacks is necessary for the maintenance
of these systems.
This material should also be able to be processed

flexibly on site and should not require any complex
machinery.

Damage causes in a sewage treatment plant
- due to mechanical wear
- through frost and de-icing salt
- due to chemical attacks or solvents
- due to concrete corrosion in closed systems

UHPC Ultra High Performance Concrete
UHPC are special concrete products with a minimum
compressive strength of 130 MPa and a water/cement
ratio of less than 0.2.UHPC products can be used very
well for the rehabilitation of concrete - and steel structures.
UHPC products can increase to be rehabilitated
construction next to the corrosion protection even
with admixture of ceramic aggregates the static
bearing capacity.

Benefits of UHPC
- Easy installation as spray, mortar, cast
- Very high corrosion resistance
- Extremely wear-resistant
- Extreme low to no carbonation
- Usable at very high humidity
- Very high impact strength
- Extreme low chloride permeabilit
- Very high resistance to mechanical loads
- No pore formation
- Maritime and port water resistant    
- Installation in the water possible
- Duration resistant
- The standard drying time is under 48 hours
- Penetrates into the smallest joints and cracks,
   and closes them permanently
- Joint less installation
- Very good thermal shock resistance
- Absolutely frost and de-icing salt resistant

Machining UHPC concrete like metals

UHPC is a very unusual material that is still

far too little considered by architects and
designers. It is still viewed and processed
like a normal concrete.
Our view is more that we design and
manufacture UHPC to treat it more and more
like metal. UHPC in the right quality can
already be machined with tools from the metal
industry. Very high accuracies can be achieved
here whether in surface processing or in shape
processing.
The surface treatment can either be carried out
using special UHPC casting molds or by
identical processing steps as for metals, or
combined casting and subsequent processing.
There are no limits to the design options here.
In terms of shape, metalworking tools or machines
can be used with the same objective as metals.

Architects, designers and artists have not even
used a fraction of the technical possibilities.

One example is the use of computer-controlled
water jet cutting machines. For a customer, we
should test the possibilities of making special
bevel cuts as plate slots that cannot be cast in
this way. Additional cutting tests were carried
out to check which geometries can be cut and
what minimum wall thicknesses can be achieved
between the individual cuts. With the right
combination of UHPC binder, unit quality and
setting of the cutting machine, amazing results
can be achieved. The tested UHPC plates had a
plate thickness of 15 - 25 mm, no metallic
reinforcement and were dried for 48 hours in
normal ambient temperature before they were
processed.

With the UHPC binder-aggregate combination
used in the test, cutting distances of 5 mm could
be achieved.
As soon as possible, further cutting tests will be
carried out with UHPC desert sand binders.
Water jet cutting enables complete "images" to be cut in UHPC panels or special construction elements.
With this type of material / machine technology, it is possible to produce a large number of facade panels with an elaborate cut design at low cost in a short time.

WPE DK International

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