•
Base friction.
•
Slab restraints.
•
Layout of foundations, racks, pits, equipment pad,
trenches, etc.
•
Environmental factors - temperature, wind, humidity.
•
Methods and quality of concrete curing.
Generally, contraction joint patterns should divide slabs into
approximate square panels per the recommended spacing
shown.
Recommended contraction joint spacing
Concrete thickness, mm
(in.)
90 (3.5)
100, 114 (4, 4.5)
125, 140 (5, 5.5)
150 (6) or greater
At all intersecting cross cuts, install Husqvarna joint
protectors at each joint to prevent joint damage. Install an
additional joint protector where the right wheel will cross the
joint to prevent concrete damage.
Maximizing the Soff-Cut system
'The timing of concrete operations - especially finishing and
jointing - is critical...Failure to address this issue can
contribute to undesirable characteristics in the wearing
surface as cracking..." (Extract from the foreword of the
American Concrete Institute (ACI) 302.1 R-96.)
The patented Soff-Cut Ultra Early Entry system has
revolutionized the method used to control random cracking.
While Soff-Cut is being specified more today than ever,
sometimes the ultra early-entry spec is not always followed on
the job site.
In order for the Soff-Cut system and an experienced
Husqvarna contractor to do a satisfactory job, the following
components must exist to meet the 'specification":
•
A Soff-Cut Ultra Early Entry dry up-cut saw.
•
A Husqvarna Excel Series dry-cutting diamond blade.
•
A Husqvarna anti-ravel skid plate installed with every new
diamond blade.
•
An operator skilled in using the Soff-Cut Ultra Early Entry
cutting system.
Without this, joints can not be cut clearly enough to control
random cracking before it starts, which is what the building
owner is paying for.
The ACI Spec 302.1R-96 says it best:
'Early-entry dry-cut saws use diamond-impregnated blades
and a skid plate that helps prevent spalling. Timely changing
of skid plates is necessary to effectively control spalling. It is
best to change skid plates in accordance with manufacturer's
recommendations...The goal of saw-cutting is to create a
weakened plane as soon as the joint can be cut...The timing
of the early-entry process allows joints to be in place prior to
development of significant tensile stress in the concrete..."
The Portland Cement Association (PCA) engineering bulletin,
Concrete Floors on the ground, also states:
14 –
English
OPERATING
Maximum spacing, m (ft.)
2,4 (8)
3,0 (10)
3,6 (12)
4,5 (15)
'Proper jointing can eliminate unsightly random cracks.
Aspects of joining that lead to a good job are choosing the
correct type of joint for each location, establishing a good joint
pattern and layout, and installing the joint at the correct time...
Timing of joint sawing is critical...Lightweight, high-speed,
early-cut saws have been developed to permit the joint
sawing very soon after floor finishing, sometimes within 0 to 2
hours...if the cut is sawn within a few hours after the final
finishing, random cracking can be controlled..."
Husqvarna has the only Ultra Early Entry dry-cutting system
(Soff-Cut) which controls random cracking through the early
timing of the cut. With the patented Soff-Cut method, control
joints are usually cut within 2 hours after the finishing process.
Joint cutting should begin as soon as the concrete will
support the weight of the saw and the operator at each joint
location and before final set.
If the joints are not being cut within this time frame then the
Soff-Cut Ultra Early Entry method is not being followed and
building owners are not getting what they are paying for or the
finished product that they expect.
Transport and storage
CAUTION! Use proper lifting technique. The
!
saw should be lifted from the center handle
on the roll cage.
•
If two people are lifting the saw, use the roll cage bar on
each side of the saw and lift with two hands.
•
Always store the saw in a completely lowered position and
secured from moving.
•
Close the fuel valve.
•
Secure the equipment during transportation in order to
avoid transport damage and accidents.
•
Store the equipment in a lockable area so that it is out of
reach of children and unauthorized persons.
•
Dismantle the blade before transportation or storage of
the machine.
•
Store the machine and its equipment in a dry and frost
proof place.