Multiquip WRS5200 - Manual (Page 30)

PAGE 30 — WRS 5200 RIDE-ON ROLLER SCREED — PARTS MANUAL — REV. #2 (08/09/02)
The Whiteman WRS-5200 roller screed provides all of the
benefits of labor savings, high productivity and enhanced
floor flatness/levelness qualities. To order to maximize these
benefits, care must be taken to insure a successful applica-
tion. :Inadequate substrate and form support can lead to
form failure causing unnecessary job delays, and expenses
while contributing to poor floor flatness and floor levelness
ratings. The intent of these specifications is to establish
minimum guidelines to help the contractor choose the most
economical and effective form work/support system to fit
any job site needs.
It is recommended that at least the day prior to the concrete
pour, a dry run be accomplished to test the load capacity of
the forms and substrate. Proper job planning is essential to
a successful application.
The WRS-5200 weighs approximately 4000 .lbs (at 52 feet
of screed) approx. 2000 lbs. per side. Any screed support
(forms, rails, rail supports and substrate) must withstan0a
2s0s.0 lb. “point load” at a 2:1 safety factor.
SUBGRADE/DECK FORMS-
Subgrade must be sound enough to support slab edge forms
and bracing as well as the load imposed by the screed and
its supports. Potential deflection, as in the case with metal
and plywood decks, should be considered when determining
brace and support spacing. Soil subgrades must be well
compacted and must be able to support bearing pressures
greater, than or equal to those imposed by the screed sup-
ports and the slab forming. For proper bearing support, shims
should be used to adequately distribute loads where grade
is not level or is soft. Use standard AC:[ concrete form pres-
sures when calculating lateral loads on slab edge forms
WRS-5200 — FORM SPECIFICATIONS
WOOD FORMS-
Wood forms are NOT a preferred method of screed support.
Because of the concentrated bearing loads by the screed,
wood is not a good support material. Nominal 2x (1-1/2’7
No.2 Douglas fir is calculated to support a maximum of 1000
lb. The grain could crush and splinter causing level varia-
tions and potential failure. 4x (3-1/2") lumber for edge form
should be acceptable.
SCREED RAILS AND SUPPORT-
Screed rails (Figure 19) and supports, independent of slab
edge forming are a preferred method. Due to strength, de-
flection and traction considerations, 2.5" x 2.5" x 875 (3/16")
wall structural steel tubing with adjustable supports spaced
as shown in the attached drawings. Standard deflection with
a 3/16" wall thickness for the above configuration is 1/6" in 4
ft. Refer to standard material charts for other configurations.
STEEL FORMS-
Paving forms with 90° lip-edge at bottom with stake pockets
is preferred. If soft or unleveled subgrade is encountered, a
2x bearing pad and/or shims should be used under the steel
forms for additional bearing support. Depending on slab thick-
ness and subgrade, forms may require diagonal bracing.
These specifications are provided as a service to illustrate
the application of MQ - WHITEMAN products only and are
not intended to be fully directive or cover all engineering
details, MQ - WHITEMAN will not be responsible for the
improper application of its products.