Opus Concrete for Art 2009 2

8/10/2019 Opus Concrete for Art 2009 2

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Concrete

or

a

t

Rarnnuruo

ennHn^

Concreteechnology

t the

musicians' ouse

at lnselHombroich

The manufactureof aesthetic air-facedconcretewith a

perfect

surface

represents challengeeven under

normal conditions.However,he condi-

tions at

Insel Hombroich raised his craftsmanship o a work of art. A

musicians' ouse was built on the site of the

former rocket station near

Neuss n WesternCermanyaccordingo the

plans

by he New Yorkarchitect

RaimundAbrahamand deserves

espect

n terms of both architecture nd

bui ld ing echnology.

(u

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5

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(U

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l;

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rc

The estate agent

and art lover Karl-Heinrich

Mller

(1936-2007)

had

the

vision many

years

ago of

a

place

where

artists

from all

genres

could live and

work. He

put

this

idea into

practice

with

the

'Stiftung

Insel

Hombroich' (Hombroich Island Trust). As part of this

idea, the building by

the New York architect

Raimund

Abraham is dedicated

o musicians.The building

was

presented

as long ago as 1996 at the

Biannual Inter-

national

Architecture Exhibition in Venice.

However, it

was to be another ten

years

before building

work

began.

During that time the

project passed

through

several

planning

processes

that

were

accompanied

creatively by the builder.

Today, four

apartments, a

large common room, a music library and a recording

studio

are

planned

in

the steel

reinforced concrete

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3/4

respective

pouring

situation. All three

types

of

concrete

were

of consistency lass

F3, i.e. they

were

soft to plasticand did not flow. Over and above hat, a

wire mesh mountedat right angles o the

direction of

flow

prevented

the concrete

from slipping on the

strongly inclined

formwork. The architect s design

envisaged slab

with a thickness f almost50

cm. In

order

to reduce the

weight

of

the concrete disc,

spherical

plastic

hollow bodies

(Cobiax)

with

a

diameterof approx.

25 cm

were

ntegrated

n

the

con-

crete

slab.There ask

s

to create

argeair chambers

n

the concrete

where

statics

allow. Due to their

low

gross

density, however, the

hollow

bodies

act like

buoys and

loat

to the

surface. n order o

prevent

his,

the

manufacturerdelivered the balls

in reinforcing

cages,with the aid of which it was possible o mount

them

in the desired

position.

For

the

musicians house

these steel cages

were concreted n a 15 cm thick

concrete ayer and in this

way fixed. The 30 cm thick

concrete

pouring

above that completely

encases he

plastic

hollow

bodies.

The whole thing is topped off

by a 9 cm thick covering ayer. Polypropylene ibres

have been added to this

layer in

order

to

prevent

shrinkagecracks

as

the concretesets.

n order that the

concrete should

have an aesthetically appealing

appearance,t was he architect s

ish

that all surfaces

should

have

a uniform

colour. n addition o numerous

other

factors, t is in

particular

he sand added o the

mixture that

plays

a decisive

part

in the colour of the

concrete.

However,

sand

is a natural

product

and

varies in

colour, dependingon

its origin. Given the

construction

eriod

of l5

months, t therefore ppeared

to

those responsible o be a

good

idea to stockpile

sufficient

quantities

of sand.A total of

1500 metric

tons of the aggregatewere stored and used in the

preparation

of the concrete.On top of that,

the

experts

from

Heidelberger Beton

chose

an iron Portland

cement

CEM

II/A-S 42.5 R) as he binding agent.

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32


4/4

Lnve

BY AyER

Multi-layer

slzrb

onstructions

re

nothing

or-rt f

the

ordinary

in concrete

buildin-e ractice.

n

order

to

manufacture

monoli thic

slab

using

his

construction

method.

a force-locked

onnection

etween

he indi-

vidual

ayers

s necessary.

he

easiest

ay

to

achieve

this s

to apply

he

concrete

resh-in-fresh.

his

entai ls

pouring

the next

layer

of concrete

onto

the

previous

layer

before

it has

set.

However,

n the

case

of

the

musicians'

ouse

his wns

not

continuously

ossible.

So that

the arti f icial

stone

would

be sol id

enough

o

allow

the hollow

bodies

o

be fixed,

the

employees

from

Heidelberger

Beton

recommended

hat

a

period

of

two dzrys

e allowed

between

he

first layer

ancl

he

subsequent

ouring

processes.

nly

then

could

th e

second

oncrete

ayer

be

poured.

This

contained

a re-

tarder, .e. erchemical hat slows down the concrete

setting process.

As

a result

of

this, the

building

workers

had

sufTicient

ime

to

pour

the final

layer

on

the

sti l l fresh

concrete.

The

monolithic

slab

thus

created

was

subsequently

reated

using

special

_erind-

in_e

achines,

o-cal led ower

rowels.

g

Architecture

Prof .

ip l . - lng.

a imund

braham,

ew

York

Vienna

Structural

ngineering

Dip l . - lng. ors tKappauf

Construction

ite

management

Andreas

i tpass

nd

Susanne

chwingen-Hi tpass

rch i tek ten

Stockka pstra

e.

8

40477

Dsseldorf

Cermany

T +49

zn

46959328

Concrete

Heide lbergCement

C

Ber l iner

t rae

69rzo

Heide lberg

Germany

T +49

6zz1

48l

g48l,F

+49

6zzt

48r

954o

www

heidel

ergcement.com/de

Heide lberger

etonNordwest mbH

Co.KC,

Cebiet

Rhein land

Max-Planck-itr.

z

5o858

Kln-Marsdor f

Cermany

T +49

2234

9993

o,F

+49

2234

gg3

11o

Formwork

echnology

Deutsche

oka

Schalungstechnik

mbH

Frauenst rae

35,

D-8zzr6

Maisach

T

+49

8t4t

394o,F

+49

8t4t

3946t83

Deutsche.Doka

doka.de

www.doka.com

Void

plastic

ormers

echnology

Cobiax

echnologies

mbH

Heide lberger

t rasse

-8

64283Darmstadt Cermany

T

+49

6t5l

9t

816

oo, F

+49

6.t5.r

t

8t6 zz

i

nfo.ge

ma

ny@co

iax.com

www.cobiax.com

33

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Documents

Opus Concrete for Art 2009 2