Combi-walls are piling walls that are comprised of high modulus structural components inter spaced by lighter sheet piles. The high modulus components known as king piles can be tubular, box, bearing or other types of fabricated piles.
Here is the content list:
Characteristics of combi-walls
Installation process of combi-walls
Precautions for using combi-walls
Combined columns are set at both ends of the combi-walls, and the top and bottom are connected with the ring beam formed by the cast-in-place floor slab, the middle is made of concrete small hollow blocks or porous bricks and other wall materials, and no core columns are used inside the combi-walls, and reinforcement bands are set at every 800-1000mm height to form a wall of constrained masonry combined structure.
Depending on the application. combi-walls are installed in the spaces between the pipes with a vibratory hammer and are aligned with pipes using welded interlocking points. Other pile cross-sections such as H-piles can also be combined with sheet piles to form a combi-wall.
In the whole building, a new structural system with high seismic strength, easy construction and economical cost is produced for six-story residential buildings with seismic fracture degree greater than 8 degrees, and the construction difficulty and civil construction cost are similar to those of brick and mortar structures. According to the seismic requirements of 8 degrees of crack resistance, this combi-wall can be used to build small high-rise residential buildings, or small high-rise residential buildings with ground floor frames.
The mounting brackets are used to install the combi-walls and form a whole wall assembly after installation to achieve the basic function of the wall, and the height of the vertical brackets can be set as needed to control the height of the manufactured wall blocks to meet the use of the combi-walls
Each combi-walls block can be assembled and disassembled independently for easy adjustment and replacement, and each block is assembled by its own track slot and fixed by its own clips, so it is independent, and after forming the whole combi-walls, the adjacent combi-walls are constrained, and the wall block on the far side is constrained with the vertical frame for overall stability.
If a single wall block is damaged, it can be replaced individually at a lower cost, and the damaged state will not affect other wall blocks, thus ensuring the service life of the combi-walls.Therefore, the combi-wall has good solidity, the structure can be flexibly adjusted, each combi-wall is independently assembled and disassembled, and can be adapted to different use requirements.
It is essential that a stable, heavy, adequately rigid and straight pile-driving template frame, adapted to suit the length and weight of the pilings, be provided.
The combi-walls are fixed into position within the template using welded bracket guides which take into account width tolerances.
Driving of the combi-walls must be carried out with extreme care in order to ensure that they are embedded straight and vertical, or at a prescribed batter, thereby guaranteeing that they are parallel to each other and at the required spacing.
The driving sequence of the combi-walls must ensure that the pile toe encounters soil uniformly on its total circumference and not just on one side.
In general, all of the combi-walls should be driven in sequence to full penetration without interruption.
Following successful completion of this, the intermediate light piling sections can be set and driven.
During the setting and driving operations of the combi-walls, a constant check (using theodolites) should be made of their alignment in relation to the wall.
When the guide frames have been removed, a final survey should be made to ensure that the deviations in the distance between the combi-walls are within the acceptable tolerances in order to allow the proper installation of the combi-walls
If the deviations are outside the specified or practical tolerances, then either the intermediate piles have to be adjusted or the combi-walls must be extracted and re-driven.
To overcome difficult driving conditions, it may be possible to use: jetting
Excavating inside the combi-walls or any other the ground pre-treatment methods normally adopted for sheet piling.