Piling Mat Level

The tell tale shall be constructed from one layer of geotextile membrane that is overlain with 150mm of crushed concrete.

Piling mat level. After achieving formation level all piling mats must be provided with a tell tale layer to identify any compromise in the integrity of the piling mat. A soft spot in the surface of just 1 sq. For each additional 0 3 m increase in cut off level below the working level additional coverage of minimum 50 mm shall be allowed. The height of the top of the piling mat needs to be agreed.

The specification of pile cut off level is as follows. The edges of the mat and the ramps onto and off it should be clearly marked. This enables steel to be placed flush with the piling mat thus enabling the rig and attendant excavator an unobstructed site reducing the risk for pile damage. For cast in situ piles under bentonite the level of the platform must be at leat 1 5 m above natural groundwater level.

Typically the top of a piling mat will be around 600 mm above the pile cut off level and it will extend beyond the outermost pile positions by at least 2 m. This inspection must be recorded and photographic evidence retained to confirm the integrity of the formation level. Times and t ype of equip ment and mat erials used will be r ecorded in th e pile bore. All pile shall then be concreted by using the trem ie.

The lecel of the platform might be determined by the phreatic level. Where cut off level is less than 2 5 m below the ground level concrete shall be cast to a minimum of 600 mm above cut off level. Piling rigs and cranes requires the input of realistic parameters for the properties of both the platform material and the underlying stratum. A common problem when designing piling mats or working platforms for tracked plant comes from deriving strength and density parameters for near surface soils from site investigation test data which is taken from the base of a service clearance pit at 1 20m below ground level.

Level with a suitable material the next. All piling mats must be visually inspected by a competent individual once they have been constructed to formation level. M can be enough to unbalance a rig. The recently published bre design method for calculating the thickness of the working platform for tracked plant e g.

Neil foundations systems would recommend that the top of the mat is generally 640mm above pile cut off level.