Construction of Petronas Baratte Piles

Barrette Piles The diaphragm wall panels can work individually, as piles, but with rectangular sections, with high resistance to vertical loads. In this case, they are called barrette piles.

Metodologia Executiva

Excavation:

It starts with the execution of the short wall (wall) tab, along the axis of the wall and buried in the ground, with the usual depth of 1.00 m. The function of this wall is to maintain stable the top of the panels, as well as serve as an initial guide for the digging tool. It also serves as a support and reinforcement tube hopper.
In some cases, very special may be employed guard rails guiding metal or precast concrete, however, are not very advisable, because some characteristics, such as bob and alignment can be compromised. Then, the positioning diafragmadora and starts the excavation with “clam shell” simultaneously with the filling of the hole with mud stabilizer to the projected depth in design. The tool “Clam Shell” penetrates the soil and, when full, the rod is raised and the tool is automatically emptied by opening.
As the excavation proceeds, care should be taken bob excavation tool, as well as the level of the slurry stabilizer, always within the limits of the guardrail guide. The slurry stabilizer has the function of ensuring the stability of the hole (avoiding the use of the coating in soil) and maintaining the suspension resulting from the disintegration of waste terrain.
The procedure is to clean the bottom of the slide with his own digging tool, removing the viscous and dense. In the case of using bentonite slurry, it should fit within the parameters of the mud required to replace it or desarenando pumps it through submersion.

Placement of Armour:

With an assist crane, the armature is hoisted and placed on the panel so as to allow passage of the tube when the hopper for the concrete. The armature is supported on the short wall guide in order to avoid commuting at the time of concreting. Should be established to ensure the roller spacers required overlay.
Along with the armor are placed tubes or plates-knuckle, smeared with mold release and raising up of alignment. When there is need to use the mirror plates, they should also be placed in this point, too greased with release agent.

Concreting:

After placing the reinforcement in the panel, the concrete begins immediately. The system used is the same concrete implementation of bored pile, the submerged, namely that runs upwards in a continuous and uniform manner. To do so, are mounted concreting pipes, hopper. In order to prevent the sludge being mixed with the concrete cast, a ball is placed inside the tube at the beginning of the concrete, which is expelled by the weight of the concrete column.
During the concrete placement, the pipe sections will be executed whenever required, ensuring that the tip of the tube hopper is immersed at least 1,50 meters in the concrete.
Retires, at the beginning of the castable, tubes or plates, gasket and plate mirror. Thoroughly clean the joints of adjacent panels eventually concreted already, by mechanical action of the wiper.

The concrete shall conform to the following specification:

• Cement consumption ≥ 400Kg per m³ to factor a/c ≥ 0,6;
• Aggregate: Stone No. 1, rounded avoids lamellar form, being forbidden the use of powder-stone, sand 35% to 45% by weight of aggregates;
• Rebate = 20 ± 2 cm.

Pre Molded Diaphragm Wall

To reduce the weight of precast wall can be concreted record “in situ”. In this case, it is suggested the use of cast slabs, where the concrete of the plug is held inside the plate.
To ensure the tightness of the joints, the panel with the excavated slurry stabilizer is set to “coulis” (mixture of cement and bentonite + water) before placing the preformed plate.
After placing the preformed plate of concrete, “coulis” fills the space between the seals, preventing the passage of water.

Plastic Diaphragm Wall

The plastic diaphragm wall element forms a “impervious” “coulis” (mixture of cement and bentonite), in proportions that vary depending on the desired permeability, preventing the flow of water or fluid undesirable.

Parede Diafragma Pré-Moldada