Reinforced Concrete Piles Cast Using 3-Sided Shaped Coppha Mold

According to the detailed pile design, RC piles

+ Tip pile type (C1)

+ Body pile type (C2)

2. Prepare the pile casting ground:

With an area of 9,400 m² Land used, of which: - Steel processing factory area is 1,200 m² with full machinery and equipment for production such as cutting, bending, punching, corrugated iron cutting, compressing machines... - Yard area of 8,200 m² production, molding and drying of concrete; More than 200 sets of shaped pile casting molds made of steel and T-gauge glassfrom 250x250x12000 to 500x500x12000. Before pouring concrete, the surface must be cleaned and all piles of other constructions must be gathered in one position at the inner corner of the yard.

 3. Equipment used for casting reinforced concrete piles:

– 500-liter concrete mixer from China

– Water pumps from South Korea and China

– Vietnamese welding machines

– A-frame crane Q = 5 tons.

– Chinese vibratory compactors

– Chinese hair cutting and bending machine

– Steel formwork of various types: 200, 250, 300, 350

4. List of main supplies:

– Cement: Joint ventures, Ha Tien, Sao Mai….

– Stirrup steel: as per design.

– Main steel: according to design

– Steel plates: according to design

– Yellow sand: Dong Nai….

– 1x2 crushed stone: as required

– Water: Use well water that has been filtered through a system that has undergone testing and proven stable for long-term use.

5. Formwork work:

– Use prefabricated steel formwork with all necessary accessories such as clamps and supports. The formwork surface must be flat and coated with a layer of waste oil to prevent sticking. The surface of the pile casting yard must be flat, smooth, and coated with waste oil to prevent sticking.

– Steel formwork must be perpendicular to the foundation surface, secured by a system of shaped clamps and adjusted in size using wooden wedges, with a clamp spacing of 1.5 to 2 meters.

– The end caps of the formwork must be made of steel or wood, planed smooth to create a flat surface, and must be perpendicular to the formwork on both sides.

6. Reinforcement fabrication and erection work:

– The main reinforcing steel is straightened and cut to the correct size, ensuring that the steel is of the correct type as specified in the design.

– Stirrup reinforcement is straightened using a winch, cut using a bending machine, a bending table, or a machine to the correct design dimensions, and the spacing of the stirrups is as required by the design.

– The stirrup steel is connected to the main steel using 1 mm thick steel wire.

– The main steel is connected to the pile head detail box by welding, using Viet Duc welding rods.

– The pile head housing is machined to ensure that all four edges of the pile face lie on the same plane, guaranteeing a square shape according to the design dimensions.

– The pile reinforcement steel is fabricated and assembled in individual cages according to the design and is inspected by supervisor A before being installed into the formwork.

7. Concrete piles:

– Concrete for casting piles will be mixed using a 500-liter mixer, following the designed concrete mix proportions.

– The speed of the concrete mixer and crane moving to the concrete pouring location (round trip) is ³ 8 minutes.

– Before mixing concrete, ensure that the sand and aggregate are clean and free of impurities, and that the particle size distribution is tested. Use a 1.5 KW vibratory tamper to compact the concrete piles, compacting the concrete as it is poured. Use a trowel to finish the surface.

– The outer surface of the pile must be flat and smooth. The pile head surface must be smooth and perpendicular to the longitudinal axis of the pile. For the pile tip sections, the pile tip must coincide with the center of the pile.

– During the concrete pouring process for piles, samples must be regularly taken for testing according to regulations.

– Curing of concrete piles after casting is carried out using natural curing methods. Approximately 4-6 hours after pouring the concrete, when the surface of the concrete has set and does not sink when pressed by hand, watering is carried out for curing. The curing period is continuous for a minimum of 3-7 days, depending on whether the weather is humid or dry. In the following days, the structure is always kept moist.

– When the concrete reaches 25% of its design strength (after 12-16 days).^H according to the prescribed experiment) then proceed to dismantle the formwork. Use red paint to write on the pile head and face: name of pile section (C1; C2), date of pile casting.

8. Measures to ensure quality and progress:

Construction complies with normative processes in basic construction, ensuring Vietnamese standards according to the following types of work:

– TCVN 4055 – 1985: Construction organization.

– TCVN 4453-1995: Monolithic concrete and reinforced concrete structures – Construction and acceptance regulations.

– TCVN 5592-1991: Heavy concrete – Requirements for natural curing

– TCVN 4252 – 1988: Construction and Acceptance Regulations – Procedures for preparing construction design documents.

– TCVN 1770 – 1986: Construction sand – Technical requirements

– TCVN 1771 – 1986: Construction crushed stone – Technical requirements

– TCVN 1651 – 1985: Construction steel – Technical requirements

– TCVN 4586 – 1987: Water for concrete and mortar – Technical requirements

During the construction process, the unit strictly implements the acceptance process as follows:

– Steel reinforcement inspection – Formwork inspection – Concrete pouring.