Concrete Work
Precast Concrete Elements
Precast concrete element systems can be used for floor slabs, facades, external elements such as bay windows, staircases and internal partition walls. Take a facade for an example. The mould is carefully engineered to the required profile and dimensions and is made of steel instead of timber. Unlike timber formwork, it can be reused very many times with minimal distortion or damage. Locations for boxing-out, conduits, window frames and reinforcement are precisely marked and fixed into position. Once all the preceding operations are completed and inspected, the concrete is poured, compacted and finished, and the curing of concrete proceeds in a controlled environment. At a predetermined time after casting the facade will be demoulded and set aside mechanically for subsequent dressing of the unit such as with tiling.
Precast facade
Precast staircase
As the facade is cast to the designed profile and dimensions the layout of tiles can be planned in such a way that only minimal cutting of tiles is required. Tiling can be carried out at ground level in the prefabrication yard where a safe and comfortable working environment prevails. For tiling in-situ, the workers otherwise need to work outdoors on bamboo scaffolding hanging at high levels. Good quality of tiling work can be much better provided and maintained by a small group of experienced and skillful plasterers under factory conditions where properly run quality assurance procedures can also be more easily applied.
Prefabrication yard on site
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Upon delivery to the site, the precast facade will be lifted by crane to the designed position, secured with temporary bracing and fixed into position by non-shrinkage grout. Part of the concrete slab adjacent to the facade is left unbuilt until the facade is fixed in position after which this part is concreted to form a homogenous tie between horizontal and vertical planes. |
Transfer of prefabricated facade to the working level
Precast elements may be made in a casting yard on site. It is believed that precast concrete construction is about 25% more productive than the conventional method of construction. Additionally, because of mass production, the materials can be better utilized and wastage can be kept to a minimum. The use of formwork can also be reduced by the use of precast concrete units.
The precast facade is secured with temporary bracing
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However, there are some limitations in using precast concrete. If precast units are only small in quantity, the construction cost will be high. In addition, storage and transportation of precast units can also be a problem for construction sites located in congested urban areas. |
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China State Construction Engineering Corporation 76 Hong Gang Road, Luo Hu District, Shenzhen, P.R.C. Tel: 2823 7888 Fax: 2865 5939 |
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Shen Zhen Sun Wah Concrete Products Company Limited Niu Shing Village, Nam Shan District, Shenzhen, P.R.C. Tel: 2893 4648 Fax: 2494 7251 |
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Golden Trend Construction
Limited Bai Sha Shui Village, Long Xi, Long Gang District, Shenzhen, P.R.C. Tel: 2380 9605 Fax:2414 5766 |
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Sun Fook Kong Construction (Concrete Products) Limited Shu Gang Road, Shekou District, Shenzhen, Guangdong, PRC Tel: 2828 1688 Fax: 2827 6275 |
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Lamma Rock Products
Limited Architectural Member Engineering Company Building, Huang Qi Town, Nanhai, Guangdong Province, P.R.C. Tel: 2398 4018 Fax: 2789 1040 |
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Unicon Concrete Products (Hong Kong) Limited D.D. 95, Lot No. 9-12, Ho Sheung Heung, Sheung Shui, N.T., Hong Kong Tel: 2477 0867 Fax: 2478 6220 |
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Main Kind Industrial Limited Xiangyuan Village, Longgang Pingdi Town, Shenzhen, Guangdong, P.R.C. Tel: 2336 1262 Fax: 2336 1077 |
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Unicon Concrete Products (Hong Kong) Limited Heng Li, Dongguan, P.R.C. Tel: 2477 0867 Fax: 2478 6220 |
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Orientfunds Precast Limited Fu Lu Sha Region, Sha Tian Town, Dongguan, Guangdong, P.R.C. Tel: 2546 2612 Fax: 2517 0873 |
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Wai Hing Construction Materials Company Limited West Nan Gang Road, Nan Gang, Huang Pu, Guangzhou, P.R.C. Tel: 2715 6942 Fax: 2713 0762 |
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Redland Precast Concrete Products Limited Little Montana Island, Zhuhai, P.R.C. |
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Yau Lee Wah Concrete Precast Products Company Limited Qinghu Industrial District, Heping East Road, Longhua Town, Baoan Qu, Shenzhen, Guangdong, P.R.C. Tel: 2753 4388 Fax: 2753 4300 |
