Slip-forming,  continuous poured, continuously formed, or slipform construction is a construction method in which  concrete  is poured into a continuously moving form.  Slip-forming is used for tall structures (such as bridges, towers, buildings, and dams), as well as horizontal structures, such as roadways. Slip-forming enables continuous, non-interrupted, cast-in-place "flawless" (i.e. no joints) concrete structures which have superior performance characteristics to piecewise construction using discrete form elements. Slip-forming relies on the quick-setting properties of concrete, and requires a balance between quick-setting capacity and workability. Concrete needs to be workable enough to be placed into the form and consolidated (via vibration), yet quick-setting enough to emerge from the form with strength. This strength is needed because the freshly set concrete must not only permit the form to "slip" by the concrete without disturbing it, but also support the pressure of the new concrete as well as resist collapse caused by the vibration of the compaction machinery.

          At Steelformer Co., Ltd, we highly specialize in vertical slip-forming.  In vertical slip-forming the concrete form may be surrounded by a platform on which workers stand, placing steel reinforcing rods into the concrete and ensuring a smooth and error free pour.  Together, the concrete form and working platform are raised by means of hydraulic jacks.  Generally, the slipform rises at a rate which permits the concrete to harden by the time it emerges from the bottom of the form.

          After the slipform process is complete the hardening process usually takes anywhere from 1 hour per 30 cm’s and about 1 day per floor. 

          Typical slipform construction time may take anywhere from 1 week to 10-15 days depending on the size and height of the project. 

Concrete pouring    
   Can use almost any concrete category on the market, if pouring as layers and slumps should be between 4-5 inches.
Steelreinforcement tying                
    Tie rod under yoke legs, tied/fastened with the vertical rod and must continuously be performed during the concrete pouring process
Maintain vertical line
    Able to be controlled with an expert at hand to conduct standard work.
    Modern construction methods using slipforms requires finishing of the concrete by using a sponge and water hose to tidy up the surface
    if necessary.
    The best method for curing can be achieved by sprinkling water over the surface after the concrete pouring or spraying a film-coat which will form
     a curing membrane       over the concrete surface and also by covering the work with a Hessian wrap and then keeping the Hessian wet.

          The slipform system involves steel panel wall forms of 1066 mm in height supported with R.S.J. walers, which are formed into a rigid frame giving support to the panels at two levels which are 600 mm apart.  
          The walers are joined with bolted splice plates or corner posts depending on the type of structure.  
           These forms are firmly braced to resist distortion during the construction process by the use of steelangle bracing and tubular steel trussing. 
           Adjustable steel yokes clamp the inside and outside forms together with the correct wall thickness.
           Accuracy and rigidity are essential on any formwork and not to mention an advantage of slip- forming is that once set up, the framework remains the same throughout the project and the constant setting out of the formwork is completely eliminated. This process saves a tremendous amount of time.
           In addition to the framework being designed for strength and rigidity it is also deigned to allow simple construction of a decking platform to form a working platform for the placing of concrete, reinforcement of steel, all necessary door and window blockouts, and etc..
           Continual cleaning and oiling of the form is also dramatically reduced.  Only the exposed faces of the formwork need to be cleaned after each period of slip-forming. The cleaning can be quickly and easily done by hand scrapers and at the end of each days concreteing before the concrete begins to harden. The panel surface is then lightly oiled with the aid of a sponge.

ADVANTAGES OF SLIPFORM SYSTEMS                                                       
Saves construction time                      
    It is the fastest method of constructing vertical structures. Resulting in reduced construction periods of about 3 days for each floor.

Cost saving   
    Reduced labour costs and decreases the risk of overdue fees because the job is completed in an ample amount of time. 
No construction limits 
    Due to the continuous operation of Slipform it is suitable for most wall layouts especially silos, tank structures and extra high floor construction.
    Water retaining structures and nuclear structures will also greatly benefit from these features of Slipform construction.

    The method can now be applied with benefits to a broad range of structures of varying complexitysuch as silos, tanks, lifts and so forth.
    Slipform systems can be adapted to accommodate any type of specific requirements. Special forms can be fabricated for particular
    project requirements. Steelformer Co., Ltd. is the most experienced in this field and we guarantee we can meet any of our customers

-  Specific sets of equipment are recommended for high rise reinforced concrete walls with an area of windows or doors less than 50% coverage.
- Specific sets of equipment are recommended for high rise reinforced concrete structures with a fixed-diameter wall thickness of more than 150 mm.
- Suggested height of more than 10 floors.

          It is difficult to define slip forming costs in general terms due to the simple fact that slip-forming can provide an extremely attractive solution under such diverse conditions. However, most of the time, a considerable amount of savings can be achieved. 
          The greatest amount of savings comes in the form of early completion of contracts. With a 3 day cycle on for example, apartment buildings, construction time can be cut by over 50%. On buildings such as commercial buildings, it is usually less expensive to construct the service core using slipform.  Please do keep in mind that this also depends on the other factors of the construction process as well such as early completion of the lift motor room, early installation of the lifts and plumbing and electrical services.
          Throughout the construction process it is Important to remember that late completion of building contracts can carry a very heavy penalty. Round structures such as silos, lend themselves particularly well to slip forming and also for the fact that these structures are usually constructed on a continuous pour basis which therefore makes slip forming the only and best choice possible.

Can use almost concrete category in market,pouring
as layer and slump should be between 4-5inches.

Tie rod under yoke legs, tie with the vertical one
and must Continuously perform during the concrete
pouring process.

Able to control by expert to make standard work

Modern construction using slipforms requires finishing of the concrete by use sponge to neat.

Good curing can be achieved by sprinkle water after concrete pouring or spraying a film-forming curing membrane over the concrete surface and covering the work with Hessian and then keeping the Hessian wet.