Lift slab construction by noidarocker

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									             LIFT SLAB CONSTRUCTION
   First Step - Preparing the Panels' Forms

Prior to the tilt-up process          The first step in creating the tilt-up
beginning, the slab is poured to      panels is to draw lines on the floor
create the floor, where the tilt-up   slab where the panels will be
panels will be created.               formed and poured.
Once the lines have been drawn,     Ensuring the exact placement of
workers place brackets to outline   the critical to the success of the
where the tilt-up panels' outside   project. The tilt-up panels must be
boundaries, windows and door        sized and positioned in precisely
openings will be.                   the right dimensions and location.
                                    forms is
                                  Once assembled, the tilt-up panel
Workers build the tilt-up panel   forms create a jigsaw puzzle
forms out of wood connected       pattern on the floor slab. But the
to the braces.                    random appearance to the forms'
                                  placement is deceiving; each form
                                  is positioned precisely to allow the
                                  crews to tilt them into their final
                                  spot in the coming days.
Rebar is placed in the completed   rebar is placed in the completed
forms. Rebar is a critical         forms. Rebar is a critical
component of the tilt-up           component of the tilt-up
construction process. The rebar    construction process. The rebar
strengthens the tilt-up panels,    strengthens the panels, making
making them safer to lift into a   them safer to lift into a standing
standing position and more         position and more durable once in
durable once in place.             place.
Workers also position embeds and       With the wood forms securely
inserts into the tilt-up panels so     constructed and the rebar and
they will become part of the tilt-up   embeds / inserts in place, the
panels once the pouring takes          tilt-up panels in the photo above
place.                                 are ready to be poured with
Second Step - Pouring the Tilt-up Panels
               Workers pour the
               cement into the forms
               in a manner very
               similar to the way floor
               slabs are poured.

              Once the cement has been
              poured, workers trowel the
              panels for a smooth,
              consistent finish.

                             Workers use a variety of
                             equipment, including power
                             trowels, to make sure the panels
                             are level and smooth. These
                             panels will become the exterior
                             (and sometimes interior) walls of
                             the building, necessitating a
                             consistent smoothness or texture
                             on all the panels.
The process for building the forms    Once the cement has cured,
and pouring the panels goes           workers remove the wood
quickly. An experienced crew can      forms and brackets to leave
take a large project from bare slab
                                      the tilt-up panels lined up on
to completed panels in a matter of
two weeks.                            the floor slab.
Workers do last minute detail
work on the panels, including      Thetilt-up panels have been
drilling places for the brackets   fully prepped and are ready
to be connected.                   to be tilted into place.
 Third Step - Tilting the Panels into Place

The mobile crane lifts the tilt-up   The tilt-up panels are poured into
panel and tilts it into position     forms that provide the exact size,
over the footing. The row of         shape and door openings to meet
panels already in place give         the design specifications. The
evidence to just how fast the        panels can be massive; this tilt-
process for putting up tilt-up       up panel weighs about 50,000
panels goes. An experienced crew     pounds. The largest panel used
can tilt up as many as 30 panels a   for a tilt-up construction project
day.                                 weighed six times as much, over
                                     150 tons.
Once the panel is set in place,
the crew attaches the braces to    The crane lifts the panel and tilts
the slab to keep the panel         it into position over the footing.
standing until it is attached to   Workers help to guide the tilt-up
the other panels and the roofing   panel and keep the braces from
system.                            getting tangled in the lines.
Once the panel is set in place,
the crew attaches the braces to    Workers help to guide a large
the slab to keep the panel         mobile crane as it lifts a tilt-up
standing until it is attached to   panel into place on this Fort
the other panels and the roofing   Worth, Texas warehouse building
system.                            project.
Why do Design / Build Contractors Choose Tilt-up Construction?

Tilt-up construction provides numerous advantages over steel
buildings or traditional construction for warehouses, call centers,
distribution centers, retail stores, office buildings, storage facilities
and other types of industrial and commercial projects.

 A one- to two-story structure larger than 50,000 square feet with
less than 50% wall opening space is an excellent candidate for tilt-up

 But what are the advantages?
 Savings in Construction Costs - This method of construction uses locally
 available materials rather than ones that must be manufactured and
 shipped in. This means that raw material costs are lower, available when
 needed and less prone to price fluctuations.
 Tilt-up work crews are typically smaller than the crews used in traditional
 construction and are normally comprised of local labor. That translates to
 reduced labor costs. Because of the economies of scale, the larger the
 footprint for the building, the more these savings improve the project's
 total cost.
Fast Construction Schedule - Erecting the walls with tilt-up panels is faster
than building walls using traditional construction techniques. The trades can
begin work earlier in the process on a tilt-up project, which allows greater
overlapping of project phases. Because the building is made of ready-mix
concrete from local sources, the project is less likely to be affected by
transportation delays as well. All these factors provide for a faster, more
predictable schedule with fewer opportunities for delays and associated cost

Safety - The vast majority of the project takes place on the ground rather than
on scaffolding, reducing many of these risks normally faced by workers.

Aesthetics - Tilt-up buildings are not prefabricated. Each one is custom-
designed for the client's needs and preferences. A full range of building finishes,
wall textures and adornments, colors, even curved walls, are available with this
method. Tilt-up provides architects and designers with virtually unlimited
flexibility in crafting a building that is functional, durable and aesthetically
The benefits of a project built with tilt-up construction continue long
after it is completed:

Durability - Tilt-up buildings are extremely durable. Many structures
created in the 1940s are still in operation today, with little apparent
wear. A testament to the strength of tilt-up construction, general
contractors in earthquake-prone California now use this method for 90%
of their one-story industrial building projects.

Fire Safety - The concrete used in tilt-up panels meets the fire-resistance
standards of even the most demanding building codes. For example, a
6.5" concrete wall offers a fire resistance rating of four hours or more.
Tilt-up panels are also frequently used in the building's interior as fire

Ease of Maintenance - Tilt-up buildings require little in the way of
ongoing maintenance, outside of periodic cleaning and repainting as
desired. Concrete is impervious to insect or rodent infestation, so this
problem becomes a relative non-issue as well.
Repairs and Expandability - In the event a wall is damaged by a forklift or
truck, damages are typically more localized on a panel than in other types of
structures, like steel buildings. Also, the modular design of the panels allows
for easier repairs and expansion of the building.

Security - Facilities that require positive security and management of the
interior environment - prisons, classified manufacturing facilities,
businesses with clean rooms - will appreciate the strength and control
afforded by concrete and tilt-up buildings.

Reduced Insurance Premiums - Because tilt-up buildings have superior
fire resistance ratings and have been proven to withstand severe weather
and earthquakes, these buildings typically enjoy better insurance rates than
steel buildings or other types of structures.

Reduced Operating Costs - Concrete provides excellent insulation,
reducing the ongoing heating and cooling costs for the tenant. This
insulation extends to sound as well as temperature. Workers in a tilt-up
office building located in a noisy area will be less affected by the
environment. By the same token, a manufacturing business that generates
noise will have less effect on its neighbors and will find it easier to comply
with local noise ordinances.

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