Precast concrete construction method

Offsite construction involves construction activities performed in a factory or plant located away from the actual construction site. Owing to the location of offsite production facilities along with the possibilities provided to the manufacturers in improving assembly process, offsite construction extends numerous advantages.

Precast concrete

Similar to other construction methods, precast concrete extends numerous benefits with regard to construction process efficiency, enhanced construction programme, enhanced quality and better budget controls. Precast concrete solutions utilized for structural and ornamental elements is currently extensively utilized the world over in construction of bridges, stadia, buildings (Hieber et al. 23).

Unlike other offsite methods of construction, the precast concrete production process relies on shuttering, for instance, standard built ( e.g. hollow floor section) or personalized to suit the particular construction elements geometry (e.g. bridge elements). Consequently, precast concrete elements have proved to be greatly economical where there exist replications in a project (Wrap 12).

Precast concrete provides construction elements, which could be utilized in several ways namely:

1. Stand alone elements- they are the mainly standard construction parts which manufacturers hold in stock and deliver to the site on demand. These elements include; precast concrete beams, average sized hollow components for floors along with wall panels
2. Building systems- these are precast concrete building systems which are used to build medium sized buildings such as flats, prisons et cetera. These construction buildings depend on precast elements, which are bolted jointly on site.
3. Assembly package- these are utilized for huge projects for instance, bridges or stadia, the design divides the structure into small transportable parts to be assembled on site. The connection systems in addition to elements’ dimensions are carefully designed guaranteeing secure and undemanding installation procedures.

The utilization of precast concrete calls for significantly reduced resources on site since all elements are designed and produced in conditions unaffected by the weather, therefore, the only operations required on site are restricted to:

• Foundations preparation
• Placing the elements on position
• Sliding junction re-bar
• Grouting

Precast concrete elements require no packaging since they are designed for trouble-free handling. Thus the erection of elements will generally result to reduce or no waste (Hieber et al. 56). Precast concrete solutions assist the construction industry to decrease the generated waste on site by over fifty-percent compared to the greatly wasteful traditionally managed constructions. The precast concrete offers no need for detailed scaffolding or provisional works.  These concrete do not need bespoke shutters fabrication on site along with their succeeding discard to landfill following usage. The design stage of precast concrete guarantee design errors are speedily identified preventing fabrication errors which otherwise result in time wastage, resources and materials.  The factories mainly utilize tri-dimensional modeling software, which permits the design engineer in checking the interfaces amongst the distinct construction elements (Wrap 15).

For an engineer merging architecture along with structure offers efficiencies in numerous structures’ lateral support systems.   Corresponding efforts extended by the precast engineer offers the structural engineer the precise input prior to the final construction manuscript preparation; this limits shop drawing reviewing efforts and redesigning. External elements, concrete-framing systems or cladding-on-steel makes the elements stiff and resistant to both wind and earthquake forces (Englekirk 15).

Entire precast concrete systems enable architectural panels perform structural functions, reducing the requirement to include numerous materials   and trade (Englekirk 40). To illustrate this, spandrel panels holds floor systems also windows whilst offering final external finishes. Merging external spandrels inside the structural system offers deeper elements reducing deflections and complexities of having to design for relative movements linking cladding system and frame. Precast cores hold floor systems whilst offering protected elevators’ fire rated enclosures and stair functions (National Precast Concrete Association 12).

A wholly precast system guarantees a core/shell design single stop shopping. A single source is able to design and deliver the full system, producing a better-harmonized set of drawings, which permit construction to move in a more efficient manner.  Precast system eradicates the necessity to coordinate varying trades that exists while utilizing mixed systems supplied by distinct suppliers. Consequently, site construction proceeds smoothly for the reason that no specialized equipment is needed to move or lift merged architectural and structural parts.  The gains provided through complete precast concrete systems extend to the architect, structural engineer, general contractor, the owner and finally to the end user. This is because the precast systems offer effectual design, cost efficiency, a sturdy and long-lasting appearance that maintains its image all through its lengthy service life (National Precast Concrete Association 35).

This technique helps implementing waste lessening techniques beginning from very early as probable before manufacturing and on site construction. Furthermore, all wasted water along with wet concrete is at all times recovered and reprocessed within the mixing concrete process. Dry concrete is usually crushed to develop aggregates, which is later utilized in the concrete and sold to be used as aggregates for road construction.  The precast concrete is therefore one of the mostly modern methods of construction that ensures efficiency in construction in terms of costs and resources.

Works Cited

Englekirk, R E. Seismic design of reinforced and precast concrete buildings. Hoboken, NJ: Wiley, 2003.

Glass, Jacqueline. Precast concrete and masonry for construction industry, concrete precast construction. N.p., 2010. Web. 12 Sept. 2014. <http://www.britishprecast.org/publications/bpcfbrochure.pdf>.

Hieber, David, et al. Welcome to the Washington State Department of Transportation. N.p., 2005. Web. 12 Sept. 2014. <http://www.wsdot.wa.gov/research/reports/fullreports/594.1.pdf>.

National Precast Concrete Association. Precast solutions: A magazine for specifiers and engineers. Indianapolis, In: National Precast Concrete Association, 2002.

Wrap. “Waste Reduction Potential of Precast concrete.” N.p., 2011. Web. <http://www.wrap.org.uk/sites/files/wrap/Pre-cast%20concrete%20-%20Full%20case%20study1.pdf>.