SUBSTRUCTURE

PILE CAP

GROUND BEAM

GROUND SLAB

Functions

Pile arrangement below pile cap

Pile caps and isolated piles are typically connected with grade beam to tie the foundation elements together; lighter structural elements bear on the grade beams while heavier elements bear directly on the pile cap.

Incorporated in order to tie the pile heads together so that individual pile movement and settlement is greatly reduced. The stability of the pile group is greatly increased.

Transfer the load from the structures to a pile/pile group, the load further transfer to firm soil.

Definition

A concrete block cast on the head of a pile, or a group of piles, to transmit the load from the structure to the pile or group of piles.

Piles intersecting at a two separate points

Piles intersecting at a single common point

To distribute the structural loads to the piles.

To tie the piles together so they can act as a unit.

To laterally stabilize individual piles thus increasing overall stability of the group.

To provide the necessary combined resistance to stresses set up by the superstructure and/or ground movement.

COLUMN STUMP

Used for the vertical support and the transfer of building loads to the foundation.

Used to support timber-framed houses for which they are currently the most effective.

Simplest and most familiar footing.

Types of materials are commonly used for stumps

Timber

Concrete

Stump must have a concrete or timber footing placed underneath the base of the stump. This is to spread the load transferred to the stump from the building. This support beneath the stump is called a 'pad' or 'sole plate'.

Usually concrete stumps are provided with concrete pads poured in-situ on the site. Timber stumps are provided with timber sole plates.

Procedure

  1. Install column stump formwork.
  1. Concreting and hardening of column stump.
  1. Leveling and hardening of RC pile cap.
  1. Removal of formwork.
  1. Backfilling.

Steel

Ground cantilever beam

Refer to structure of beam on the ground.

To support brick/block work or to form a permanent shutter to the edge of in-situ concrete floor slab.

Ordinary ground beam

The most used in building construction.

Both its end are tied up at the column and lying between the two column.

Acts to bear all the loads come from the wall which constructed parallel with the beam.

Fixes and holds fitly the columns in order to stabilize it.

Ground beam normally should consist

Reinforcements

Concrete

Linkers

The size of main reinforcement play important role in determine the strength of a beam.

Does not have secondary beam, only has primary beam.

Usually used for external structure such as beam for corridor and also partition wall outside the building.

Cannot bear the loading such as ordinary beam.

Construction of solid ground slab floor should includes

Other materials needed

Functions

Slab can be design in 2 conditions

Non-suspended slab

Suspended slab

Is built when the ground is good enough to carry the load from the building.

is built when the ground is not good enough to carry the load from the building.

The slab is designed to carry the load of the building with the help from the ground support.

The slab is designed just like the floor of upper floor that can carry the load without the help from the ground support.

To received the load from the building.

To reduce pressure on the column and stump.

To support column and stump.

The main base of construction to ensure that the construction will done well.

Create the easier job on floor finishes.

Binding

Concrete bed or slab

Hardcore

To fill in any small pockets that have form during over site excavation.

To provide firm base on which to place a concrete bed.

To help spread any point loads over the greater area.

To provide clean, level and dry surface of hardcore.

Layer of sand 25-50mm thick or a 50-75mm layer of weak concrete.

Laid in 100-150mm layers to the required depth.

Each layer is well compacted to prevent any unacceptable settlement beneath the solid floor.

Acts against capillary action of moisture within the soil.

Unreinforced or plain in-situ concrete, 100-150mm thick.

Reinforced concrete, 150mm minimum.

Damp proof membrane (DPM)

Damp proof course (DPC)