Processing
of Grout
Application of the Pagel-Grout and Pagel-Anchorage
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Basics
The cement-bound
PAGEL-GROUTS capable of expansion are applied with preference in
the combination range of the constructive construction, i.e. steel-girder
construction, railway construction, and mechanical engineering to
ensure the taking-up and conduction of high dynamical and structural
loads.
In order to reach the maximum use efficiency for the respective
application case some basic knowledge and practice regarding the
application are to be taken into account these you will find
in the following summary:
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| Compounds
PAGEL-GROUTS
consist of high-quality source materials only for which the following
standardization is decisive:
Cement:
Portland cement according to DIN 1164 and/or EN 196
Surcharge:
Quartz sand and quartz gravel of different selected grain fractions,
washed and fire-dried according to DIN 4226
Concrete
additive: PAGEL NV-CONCENTRATE (BV) as concrete additive according
to DIN 1045 with "Allgemeiner bauaufsichtlicher Zulassung
and Übereinstimmungszertifikat DIBt (Deutsches
Institut für Bautechnik, Berlin) (General construction
supervision-like admission and Accordance certificate)
Concrete
additional materials: With Allgemeiner bauaufsichlicher
Zulassung and Übereinstimmungszertifikat
from DIBt (Deutsches Institut für Bautechnik, Berlin (General
construction supervision-like admission and Accordance
certificate)
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| Tests
and Admissions
Basis for the
test, supervision and foreign supervision of the Grouts is the editorial
leaflet for the application for work-mixed grouts (edition September,
1990, revised 1996) published by the study group main-committee,
concrete technology of the German Betonverein e.V. Bonn and/or from
the German Beton and Bautechnikverein, Berlin.
(Merkblatt für
die Anwendung von werksgemischtem Vergussmörtel (Fassung September
1990, redaktionell überarbeitet 1996), herausgegeben vom Arbeitskreis
Hauptausschuss, Betontechnologie des Deutschen Betonvereins
e.V. Bonn bzw. vom Deutschen Beton und Bautechnikverein, Berlin.)
Regarding the
application field drinking water the following admission
certificates are available for some products on enquiry:
recommendation of the team "drinking water matters of
the Plastic-Commission of the Federal Public Health Department
DVGW, technical rules, work sheet W270
DVGW, technical rules, work sheet W347
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Fields
of Application
grouting
below machines
grouting of fortification bolts
grouting below crane rails and bridge bearings
grouting of steel fittings in concrete
grouting of joints between prefabricated parts
grouting of joints between prefabricated parts and place
concrete
closing of openings and cavities in the concrete
production of tension anchoring
repairing grout (with connection reinforcement only)
For the field
of application regarding the production of additional tension anchoring
the calculation procedures of DIN 1045, especially the comparative
tensions of table 19 may be applied, this as an agreement with the
demands of DIN 1045 and special anchor tension qualifying tests
of PAGEL-Grouts can be submitted on enquiry.
The calculation proof must be proved by the responsible designer
on the basis of the measuring results of the respective product.
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| Grouting
of Machines
When grouting
machines, the machine elements are either adjusted to levels, fixator
or to lining plates. In any case the machine elements are fixed
via anchors to the concrete base. Grouting of the machine can only
take place after grouting of the anchoring has been finished and
the air existing in the anchoring has escaped.
Under no circumstances should this grouting of anchors be allowed
to take place at the same time as grouting the support plates, as
the included air can not escape.
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Picture 1:
examples of sub-grouting showing basis plate and anchor bar |
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| Tension
Anchorages
Tension anchorages
must frequently be produced on the building site. Either when the
use of a building has to meet new requirements, or when a factory
is switching over to other products. This is connected with the
construction of new production plants.
For the anchorage of new machine plants the producing of core drillings
has proved itself as this is a gentle productive technology. The
concrete structure within the surrounding area of the core drillings
remains practically undisturbed. With wet-drilling diamond drill
bits the needed diameter and the necessary depth can be reached
with a sufficient drilling speed. Also the drilling-through of an
existing reinforcement is possible, when having the suitable drilling
equipment.
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PAGEL-GROUT
- M24 anchor - concrete break-off
Graphic 1: diagram of an anchor bar anchorage
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When exceeding the concrete
bond stress a circular crater this as a sign of a rupture
breaks off within the upper area of the concrete.
As the drill core normally breaks off through jamming and for this
reason the break-off of the core does not take place at its deepest
place some additional cm regarding the anchoring length are to be
drilled. |
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Picture
2: The upper anchorage area must be deducted mathematically from the
anchorage length. |
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In
the upper area of the drilling however depending on the diameter
of the core - at least 5 cm (1.97") of the plug-in depth of the
anchorage length must be deducted, this is because, in the upper concrete
area the cleavage strength of the surrounding concrete is lower compared
to the bigger plug-in depth.
For the calculation of the bond stress between grout and concrete
the basic values of the permissable bond stress are taken from the
DIN 1045 this according to the existing comparible concrete
strength. |
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Table 1: DIN 1045, table
19 permissable basic values of the bond stress,
permissable. t1
in N/mm² |
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1
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2
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3
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4
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5
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6
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Bond Area
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permissable
basic values of the bond stress permissable t1
in N/mm²
for strength classes of the concrete
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B15
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B25
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B35
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B45
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B55
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1
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1
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1,4
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1,8
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2,2
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2,6
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3,0
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2
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2
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0,7
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0,9
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1,1
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1,3
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1,5
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| Steps
to grouting repairs
In the field
of concrete repair repairs using grouts are carried out in nearly
all West European countries.
In Germany this field is still reserved for PCC- and SPCC-mortars.
The background of these rules is simply said to be found in the
fact that for repairs in the constructive engineering special protection
functions are assigned to the repair mortars.
The origin of the ZTV-SIB goes back in time 20 years. At that time
no standard building materials where known which could meet the
requirements of the ZTV-SIB. As modern grouts with their material-specific
qualities have been clearly improved grouts of today meet the main
requirements of the ZTV-SIB.
Shrinkage was clearly reduced. With the products
- V1/50
PAGEL-GROUT and
- V1/160
PAGEL-GROUT
Shrinkage values
less than 1.0 0/00 are reached, the limit value of the ZTV-SIB falls
below. Less E-modules are to be found in the field of the ZTV-SIB
taking the a.m. PAGEL-products between B 35 and 45 - this
is achieved by using agents and additives. Therefore, seen from
this side of the test values a concrete repair is possible..
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| Table 2: Elasticity modules
for the various concrete strength classes according to DIN 1045 (1988)
Tabel 11 |
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2
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3
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4
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5
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6
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7
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| 1 |
Festigkeitsklasse
des Betons |
B10
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B15
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B25
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B35
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B45
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B55
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Elastizitätsmodul
Eb in N/mm² |
22000
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26000
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30000
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34000
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37000
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39000
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The following
qualifications are applicable with regard to the concrete repair:
The quality of the concrete base must at least correspond to a BII-concrete,
i.e. at least a concrete of a comparative concrete-strength class
B35.
For the repair grout a projecting reinforcement must exist and/or
is to be produced (corresponds to concrete according to DIN 1045).
The layer thickness
must amount to at least 50mm, (then this measure can (must) also
be seen on the grounds of the admission bases of the ZTV-SIB).
The composition of the grouts must correspond to DIN 1045 (only
base materials being admitted according to DIN 1045)
Only grouts are allowed (applies to V1/50 and V1/160)
Production must be covered by self-control as well as foreign supervision.
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Typical
repair grouting at a balcony ledge using V160 (B45). In principle
these works are carried
out only when having a projected reinforcement to the balcony plate
and a clip basket for balcony
ledge. |
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| Preparation
of the concrete Base
Practically every standard formula
concrete sediment on the surface is cement slurry for reasons of
its admixture and cement values.
The cement is enriched with a lot of water and has only got low
compressive strengths and also low tension strength.
Unprepared concrete surfaces do normally have a surface tension
strength less than 0,5 N/mm² and are not suitable for the absorption
of high-solid mortars (grouts).
All less adhesive surface components as well as all impurities are
to be removed until the tensionproves mass-concrete is reached.
Besides the conventional procedures
like
blasting with solid basting
equipment
milling
shot blasting
pressing and bush hammering
it is also possible to apply hand milling
tools when having defined and small surfaces. Within the grouting
area the less adhesive components are to be removed. The aggregate
grain must be exposed in order to reach a surface adhesion strength
which corresponds to the adhesion strength of the existing concrete
(>= 1.5 N/mm²) and an adhesion is achieved between the grout
and the concrete base (attention is to be paid to pre-wetting and
curing).
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| Minimum
requirements on the concrete base
Minimum quality:
comparable concrete compressive strength > B25
Cement slurry: completely to be removed until the aggregate
grain is exposed
Adhesive strength: at least 1.5 N/mm²
Cracks: to refill, to inject, to impregnate
Capillary absorbency: before grouting pre-wet sufficiently
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Product
selection
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Product
selection based on the grouting height
| product |
Product type
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Grain
size
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Grouting
height
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(mm)
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(mm)
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| V1/10 |
Standard grout
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0,1-1,0
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5-30
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| V1/50 |
Standard grout
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0,1-5,0
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20-100
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| V1/160 |
Standard grout
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0,1-16,0
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> 100
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| V2/10 |
Fast setting
grout
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0,1-1,0
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10-20
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| V2/40 |
Fast setting
grout
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0,1-4,0
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20-60
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| V2/80 |
Fast setting
grout
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0,1-8,0
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50-100
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| V2/160 |
Fast setting
grout
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0,1-16,0
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>100
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Product selection
based on the flow route
| product |
Product type
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Grain size
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Grouting
height
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Hand processing
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Mechanical
processing
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mm
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mm
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m
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m
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| V1/10 |
Standard grout
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0,1-1,0
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5-30
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4,00
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> 30
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| V1/50 |
Standard grout
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0,1-5,0
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20-100
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4,00
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> 20
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| V1/160 |
Standard grout
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0,1-16,0
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> 100
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2,00
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> 10
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| V2/10 |
Fast setting
grout
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0,1-1,0
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10-20
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1,00
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> 10
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| V2/40 |
Fast setting
grout
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0,1-4,0
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20-60
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1,00
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> 10
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| V2/80 |
Fast setting
grout
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0,1-8,0
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50-100
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1,00
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> 5
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| V2/160 |
Fast setting
grout
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0,1-16,0
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>100
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1,00
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> 5
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PAGEL-GROUTS do have the ability to
flow under continuous material supply very well. If, however,
when hand mixings the process is interrupted again
and again and resulting from this the product stops again
and again, it can on reaching a certain mass not be pushed
forward any longer from the later poured product. Even more
problematic is that layers (floes) form themselves as a result from
the later pouring. This should be avoided.
The flow ability of the product depends directly on the supply of
the mixed material. Using mono pumps (spindle drag pumps) and ensuring
a continuous adding of material the grout is constantly kept moved
and therefore it can be pushed forward far away.
PABEC I and PABEC II are supposed to be the best possible machines.
They in the meantime are equipped with a Vario-transmission as well
as a continuous water filling-system. They are able to grant an
equally mixed base product, i.e. from cement glue (E1F PAGEL ANCHOR-
and INJECTION GROUT) to grout (V1/160 PAGEL GROUT) for a longer
period of time..
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Selection of products for tension
anchoring
For the production of additional tension
anchorings PAGEL GROUTS are preferred for the vertical anchorings
as they correspond to the computation handicap of DIN 1045 table
19.
Regarding the selection of the product the ring split around the
anchor is to be treated equivalent to the layer thickness given
in the technical leaflets..
| product |
Product type
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Grain size
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Grouting
height
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Hand processing
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Mechanical
processing
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mm
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mm
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m
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m
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| V1/10 |
Standard grout
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0,1-1,0
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5-30
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<= 4,00
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> 30
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| V1/50 |
Standard grout
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0,1-5,0
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20-100
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<= 4,00
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> 20
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| V1/160 |
Standard grout
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0,1-16,0
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> 100
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<= 2,00
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> 10
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| V2/10 |
Fast setting
grout
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0,1-1,0
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10-20
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<= 1,00
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> 10
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| V2/40 |
Fast setting
grout
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0,1-4,0
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20-60
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<= 1,00
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> 10
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| V2/80 |
Fast setting
grout
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0,1-8,0
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50-100
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<= 1,00
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> 5
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| V2/160 |
Fast setting
grout
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0,1-16,0
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>100
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<= 1,00
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> 5
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| V14/10 |
Soft plastic
tamping mortar
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0,1-1,0
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5 - 30
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<= 1,00
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> 1
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For the dimensioning
of the anchorings certificates regarding the suitability of anchor
bars - and from which the computation of the necessary bond stress
comparible values can also be taken - are available to the customer
on enquiry.
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| Product
selection according to the strength development
Depending on
the demand of the construction the using of grout might be necessary
after a short and/or very short setting time.
Taking a 24 hour setting-time the compressive strengths of the products
regarding the V1/.. PAGEL.GROUT
line are normally sufficient (depending on the demand of the building
site).
In case a loading
after a few hours is demanded the products of the V2/..PAGEL-GROUT
line should be used. They also react relatively insensitively to
low temperatures when applying..
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| Development
of strength regarding the PAGEL standard products
| product |
Product type
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Grain size
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Compressive
strength development at 20°C (68 °F) after x days in N/mm² |
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mm
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1 d
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7 d
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28 d
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| V1/10 |
Standard
grout |
0,1-1,0
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37
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72
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96
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| V1/50 |
Standard
grout |
0,1-5,0
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44
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77
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98
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| V1/160 |
Standard
grout |
0,1-16,0
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46
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75
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83
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| Development
of strength regarding the PAGEL fast setting mortars
| product |
Product type
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Grain size
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Compressive
strength development at 20°C (68 °F) after x hours / days
in N/mm²
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mm
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2h
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4h
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8h
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1d
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7d
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28d
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| V2/10 |
Fast setting
grout
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0,1-1,0
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14
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20
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32
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40
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62
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78
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| V2/40 |
Fast setting
grout
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0,1-4,0
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14
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22
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32
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39
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62
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78
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| V2/80 |
Fast setting
grout
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0,1-8,0
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12
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18
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28
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40
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56
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75
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| V2/160 |
Fast setting
grout
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0,1-16,0
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12
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21
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31
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38
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56
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84
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| Development
of strength at low application temperatures
When having
low application temperatures the rate of hydration of cement-bound
building materials clearly slows down.
The example of V1/50 PAGEL-GROUT shows the various rates of hydration
for different application temperatures.
| product |
Product type
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Grain size
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at
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at
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Compressive
strength development at 20°C (68 °F) after x days in N/mm²
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mm
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°C
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°F
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1d
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3d
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7d
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28d
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| V1/50 |
Standard grout
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0,1-5,0
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41
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41
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2,2
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48
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68
|
87
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10
|
50
|
18
|
66
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74
|
87
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25
|
77
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58
|
75
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84
|
104
|
The products
of the V2 /.. PAGEL-FAST-SETTING-MORTARS line are clearly more insensitively
to low application temperatures and show a very positive compressive
strength development (basis materials not being pre-warmed).
| product |
Product type
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Grain size
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at
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at
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Compressive
strength development at 20°C (68 °F)
after x hours / days in N/mm²
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mm
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°C
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°F
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2h |
4h |
6h |
8h |
1d |
7d |
28d |
| V2/10 |
Fast setting
grout
|
0,1-1,0
|
5
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41
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18,8 |
25,0 |
28,1 |
34,2 |
43,8 |
50,0 |
62,5 |
| V2/40 |
Fast setting
grout
|
0,1-4,0
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5
|
41
|
12,0 |
15,0 |
21,5 |
23,4 |
36,0 |
58,0 |
74,0 |
| V2/80 |
Fast setting
grout
|
0,1-8,0
|
5
|
41
|
10,0 |
13,3 |
15,6 |
17,5 |
28,1 |
43,0 |
53,1 |
| V2/160 |
Fast setting
grout
|
0,1-16,0
|
5
|
41
|
3,1 |
11,8 |
12,5 |
13,8 |
28,1 |
44,5 |
65,2 |
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| Basics
of the compressive strength development when having low application
temperature
Cement-bound
building materials are not allowed to be applied when having weather
temperatures and/or temperatures of parts of building components
below + 5 °C (41°F) . As the hydration is retarded when
having low application temperatures and also in case of a sinking
of the temperatures down to frost, frost damages are to be feared.
However, frost damages can only develop in case the compressive
strengths are less than 5 N/mm2.
Therefore care
is to be taken when applying cement-bound building materials that
the temperature of + 5 °C regarding building components and/or
material is kept for the time until the compressive strength of
5 N/mm2 is reached.
Taking V1/50
PAGEL-GROUT a period of at least 36 hours with at least +5°C
must be allowed in order to reach for sure a frost compressive strength
of 5 N/mm². When
this compressive strength been reached a further increase of the
compressive strength takes place relatively quickly.
V2 PAGEL-FAST-SETTING-MORTAR
Also when having fast setting mortars there is the danger of frost
damages given in case frost
effects the compressive strength under 5 N/mm².
V2 PAGEL-FAST-SETTING-MORTARS
have, however, the big advantage that even when having low application
temperatures the compressive strength is retarded insignificantly.
Therefore, using
V2 PAGEL-FAST-SETTING-MORTARS means that awkward heat treatment
measures are not necessary if at the time of application
+ 5 °C (41 °C) are reached (temperature of weather and parts
of building components).
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| Production
of mixtures
Wetting of the cement particles with
water when having low temperatures is carried out much slower as
for example when having 20 °C (68 °F). Also the chemical
used for the deflocculating (high capacity agent) is dissolved more
slowly when having low temperatures.
Solution:
- Allow to mix for a longer period
of time.
It is necessary to use a compulsory mixer using 2/3 3/4
of the water amount, pre-mix tenaciously, add the remaining water
slowly.
- A better
mixing is reached when the mixing water is not too cold (at least
15 °C (59 °F))
(to achieve the affect of the agent).
- The total
amount of water to be added is within the given tolerance range.
A reduction of the maximum water quantity in case of low temperatures
is not necessary.
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| Fundamental
Contemplations
With regard
to the non-shrinking PAGEL-GROUTS the flow behaviour is caused by
the dry premixed high-capacity agent and not via water. For the
basis mixture approx. 2/3 of the water are given into a compulsory
mixer and mixed for about 3 minutes. Then the remaining water is
added and mixed until the necessary mortar consistency is reached.
Generally two minutes are enough for the additional mixing.
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| Free-fall
mixers
Free-fall mixers
can only mix rough mortars and/or mass building materials
containing a low amount of cement sufficiently. They are not suited
for the mixing of grouts. Especially when having fine mortars with
a low grain the mortar powder sticks to the walls of the mixer.
About a sufficient mixing effect cannot be talked when using free-fall
mixers for mixing
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| Compulsary
mixers
In case of compulsory
mixers agitating arms rotate in a fixed agatation vessel. These
mixers (compulsory mixers) force the mixture via a massive shear
force to be mixed thoroughly and by this a good and equal mixing
quality is reached. These types of mixers are often combined with
mortar pumps.
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| Hand-mixing
equipment
Using hand-mixing
equipment attention has to be paid to the compulsory mixing effect
when mixing. Drilling machines with an inserted mixing agigator
are completely unsuitable for the mixing of grouts, this because
a shearing of the mixture is not possible.
The shearing
of the mixture is only possible when using a double agigator mixer
with a low rotational speed.
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BEBA - Double
agitator mixers |
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The mixing of
grout when using a double agigator is to be executed the same way
as when using a compulsory mixer. After filling 2/3 of the total
amount of water into a mixing vessel the dry mortar is added and
mixed for approx. 3 minutes. Then the remaining water is added and
mixed till the necessary consistency of the mortar is reached. For
a further mixing about 2 minutes are necessary.
The total mixing
time amounts to at least 10 minutes. In case the mixed grout remains
in the mixing vessel for a longer period of time the material should
before applying be mixed again for a short time.
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| Conveying
For conveying
the mixed mortar screw conveyors and piston pumps are suitable.
Screw conveyors should be preferred as by this kind of conveying
a uniform mortar flow can be guaranteed.
Because of the compact and homogeneous consistency of the mortar
conveying distances of more than 100 m are possible even when having
very low heads. The diameter of the conveying hose is only depending
on the biggest grain of the product and the needed amount to be
conveyed.
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| Conveying
technique
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PFT N2 Vario
spindle drag pump
The spindle
drag pump may be used for the conveying of mortars up to a biggest
grain of 4 mm and/or 5 mm. The conveying speed can be regulated
via the Vario transmission from 0 14 l/min.
The mortar itself must be mixed in a separate mixer.
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S5 Putzmeister
spindle drag pump with a compulsory mixer put on top
This machine
equipment allows mixing and conveying at the same time. With the
corresponding
conveying speed an always sufficiently mixed product is available,
i.e. the conveying must not be
interrupted.
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| Mixing-
and conveying technique
Using the mixing
and conveying technique the mortar powder is being filled into a
storage tank. From there it is conveyed into a mixing unit and via
the rotation speed of the conveyor shaft it is supplied in a certain
volume to the mixing unit. This makes it possible to inject the
mixing water under a constant and steady pressure, the amount of
water to be added is carried out by means of a scale value in the
proportion l/h.
The grout consistency
is checked via the given expansion and/or slump at the end of the
spindle, this before the conveying hose is connected. Before connecting
the conveying hose the same should be rinsed with water (this applies
to all conveying pumps and conveying systems) in order to reduce
the side friction in the hose. Additionally cement slurry in an
amount for approx. 5 l is filled in the hose before connecting in
order to reduce the side friction clearly when starting.
In case no pre-wetting takes place and no slurry is used material
blockades can occur in the dry hose.
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May
mixing- and conveying pump
The
mixing- and conveying unit of the May mixing- and conveying pump
is situated underneath the
storage tank, therefore, a very constant powder proportion within
the mixing unit is guaranteed.
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PABEC
II Vario mixing- and conveying pump
Taking the PABEC
II Vario mixing- and conveying pump the mixing tube stands vertically
and the
dry powder is conveyed by means of a steel helix into the mixing
tube. The rotating and conveying
speeds can be led (automatically) in dependence of the
amount of water to be added.
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| Grouting
PAGEL-GROUTS
have a consistency reminding of a honey-like flowability.
The product flows slowly, however much more constant and homogeneous
as this is the case with most of the other grouts. This has the
advantage that a constant flow over very long ways is achieved without
showing any segregation.
Unimportant
whether manual or mechanical application is carried through enough
basis material must be available for the grouting object in order
to allow a grouting without interruption.
The base mixture
usually is given into a compulsory mixer, 2/3 of the water is added
and the mixture is mixed for approx. 3 minutes. In this dry form
the chemical flow agents react very well. The necessary remaining
amount of water is then added and mixed until the necessary mortar
consistency is reached. Generally a time of 2 minutes is sufficient
for the final mixing.
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| Continouos
grouting
For the grouting
of small separate supports or individual machine supports the necessary
amount of grouting is produced separately and then poured without
interruptions (caused by rests when mixing).
Grouting preferably is carried out from one corner of the not-sucking
formwork without changing the position until leaving on the opposite
side without air entrainment. Rodding is to be avoided as this trafs
air under the support plate which cannot escape.
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| Grouting
of large machine supporting surfaces
In case of either
extensive or big groutings to be carried out a continuous mixing
cannot be guaranteed when mixing the grout separately or manually.
The use of mixing- and conveying pumps instead is sensible.
If a receiving hopper was positioned at the grouting side the grouting
can take place by using a mixing- or conveying pump. Mixing- and
conveying pumps, however, do not only convey the mortar mixture
but also mix-in air.
When Grouting grouts via hose connections at the formwork only mono
pumps should be used in order to avoid air entrainment underneath
the support plate.
A combination of mixing- and conveying pumps with mono pumps is
sensible.
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| Curing
The curing of
a cement-bound building material comprises the following technical
background:
Preventation
of cracks and separation from the (concrete) basis
The tension
strength of the cement-bound products must be higher than the shrinkage
stress resulting from the shrinking if the curing is broken off.
Logically the
curing takes longer if through low temperatures the development
of the compressive strengths is reduced significantly.
Practically
this time factor can be defined:
The building material must at least have reached 60 % of its final
compressive strengths so that the tension strength is higher than
the shrinkage stress.
Consequently, when having low application temperatures the evaporation
of the water from the mortar must be prevented.
Having low application temperatures the covering with "thermo
foils has proved itself to be good practice.
In order to gain all technical handicap values grout must be cured
consequently for 5 days.
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