RUBBLE STONE SOLING

1 Name of Work & Description

Rubble Soling is a base structure of any foundation which is located under the Plain Cement Concrete of any type of Foundation like Footing, Raft, Road, Trimix, etc. general thickness of rubble soling is 230mm to 300mm.
Rubble soling is done to prepare the uniform level surface on Hard Base or on backfilled surface to work clearly and above rubble soling PCC work will be done for plain level surface. If any level difference in base of the ground then we are doing plum concrete and rubble soling with the heap of rubble and PCC.
If hard the surface level of any foundation is too deep and structure on this building in lightweight then needs to do rubble soling or plum concrete.
Types of Rubble Soling
1 Kata Soling
2 Flat Soling
3 Leveled Soling
4 Random Rubble Soling
5 Stone Pitching
6 Plum Concrete


2 IS Code No.

METHODS OF TEST FOR DETERMINATION OF STRENGTH PROPERTIES OF NATURAL BUILDING STONES: IS 1121 (Part I) - 1974

3 The Drawing Needs to Read

Following Drawing are need to read to execute the rubble soling work at site.
1 Foundation Layout
2 Raft Layouts
3 Tremix Layouts
4 Road Layouts
5 Foundation Sections
6 Raft Section
7 Tremix Sections
8 Road Sections
9 Level Drawing (For all types of a building)
10 Plinth Level Drawing (For all types of the building)

4 Location of Work

Rubble Soling will require to do at following locations
1 Below Footing PCC
2 Below Raft PCC
3 Below Tremix
4 Below WBM at Road
5 Below Plinth Level PCC
6 Below RCC Canal/Trench PCC
7 Below Storm Water PCC
8 Stone Pitching to Earthen Dam
9 Stone Pitching for Road, Bridges embankments, etc


5 Standard Procedure of Work (Step by Step)

Rubble Soling Work (Before Start the work)

1 Calculate Approximate quantity of work
2 Visit Nearest rubble stone quarry and check the quality of the material.
3 Final the Stone which is must be basalt stone and needs to make with hand-packed or rock on rock technology.
4 Order 1.5 times more material than you required. Because in a tractor-trolley if you ordered 1 brass Rubble, but it has more than 30% of voids, therefore, you need to order 1.5 times than the required material.


Rubble Soling Work Procedure is as Follows

1 Study the Drawing of Foundation Layout
2 Study the Drawing of Sections of plinth level
3 Fix the 10mm or 12mm bar at 5m or 10m interval and mark all levels on it like Footing PCC Top, Bottom Level of PCC, Top Level of Rubble Soling, Bottom Level of Rubble Soling, etc.
4 Compact all areas properly before starting the work. Don’t keep any loose material at rubble soling area. It must be compacted.
5 Shift the rubble stone near working place by the use of Labour, Tough rider, tractor, lorry or Labour, etc. Generally doesn’t use a wheelbarrow to shift the rubble stone because wheelbarrow will damage easily, it must then use it carefully.
6 Start laying of stone as per your given standards, generally, all are preferred “kata Soling”  Where we need to keep all the stone vertically places, and minimum gaps are kept between them and fix the small stone chips in the gaps of stones.
7 Fix Line Dori to the marked bar at the top level of Rubble soling. And lay all the area as per the marking, if any stone height is more than your desired height then it should be cut by the hammer.
8 Spread loose small and even good quality murum on rubble soling, fill all the gaps by chips and murum. If possible use a small plate compactor on it.
9 Check your desired height after murum filling on rubble soling.


6 Checkpoints/Checklist

Rubble Stone Soling Work Checklist is as Follows
1 Check Stone Quality is Good or Not.
2 Check the Level of Soling bottom and Top. Also, check the height of stone rubble soling work.
3 Check Murum Quality.
4 Check the gap filled by chips and Murum
5 Check the type of Rubble stone soling
6 Check if any stone is loose or not. If found loose remove it or fill the gaps by stone chips and murum.
7 Check top-level is uniform or not.

7 Equipment and Machinery

Following Equipment is required to do rubble soling work.
1 Tractor/Tough Rider
2 Wheel barrow/Trolley
3 Line Dori and 10mm or 12mm rod
4 Chalk
5 Auto Level and measuring Staff
6 Hammer
7 Plate Compactor
8 Fawda & Ghamela
9 Hand Compactor



8 Measurement and Quantity Survey

Rubble Soling Measurements are to be taken as per the following procedure
1 Calculate the Area of Soling

2 Check the Unit of BOQ which may be Square meter, Cubic meter, Sqft or Cubic feet.

3 If Unit is Square meter or Sqft then only calculate length and width of soling completed area.

4 if Unit in BOQ is mentioned as Cubic meter or Cubic feet, then need to measure the length and width of the soling completed area as well as read the item description where it may be written depth of soling is 230mm or 300mm.

5 Examples:
Item Description: Supplying and stacking at work site 300 mm size trap stone rubble for soling.
Measurement of Work: 100m X 100m
Area of Soling in Sqm: 10000 Sqm
Volume of Soling: 10000 X 0.300: 3000 Cum


9 Quality Test

APPARATUS:
A testing machine of sufficient capacity for the tests and capable of applying load at the specified rate shall be used. The machine shall be equipped with two steel bearing plates with hardened faces. One of the plates (preferably the one that normally bears on the upper surface of the test pieces) shall be fitted with a ball seating in the form of a portion of a sphere, the center of which coincides with the central point of the face of the plate. The other compression plate shall be a plain rigid bearing block. The bearing faces of both plates shall be preferably larger than the nominal size of the test piece to which the load is applied. The bearing surface of the plates when new, shall not depart from a plane by more than 0.012 5 mm at any point. The movable portion of the spherically seated compression plate shall be held on the spherical seat, but the design shall be such that it is possible to rotate the bearing face freely and tilt it through small angles in any direction.

PROCEDURE
The load shall be applied without shock and increased continuously at a rate of approximately 140 kg/cm2 of the area per minute until the resistance of the test piece to the increasing load breaks down and no greater load is sustained. The maximum load applied to the test piece shall be recorded and the appearance of the stone and any unusual features in the type of failure shall be noted.

RESULTS
The maximum load in kg supported by the test piece before failure occurs, divided by the area of the bearing face of the specimen in cm2 shall be taken as the compressive strength of the specimen.
When the ratio of height to diameter (or lateral dimension) differs from unity by 25 percent or more, the result shall be calculated to that standard test piece is follows:
Cc= Cp/  0.778 + 0.222 ( b + h )
Where Cc = compressive strength of standard test piece,
 Cp = compressive strength of the specimen having a height greater than the diameter or lateral dimension,
b = diameter or lateral dimension, and h = height.



10    On-site Experience

Engineers Review: We are working for an industrial plant and all foundation is designed on the base of shadu soil with is become loose when some waterlogging, on paper assumptions and the actual situation is totally different when we are going to excavate pit for foundation there are a lot of chances of landslides after supports given to side. Due to muddy soil and base is also shadu soil. Which is too loose we can’t get hard support to rest our foundation but due to help of rubble we are getting good solutions to rest it, we did random rubble soling and done plum concrete in shadu soil to get a hard surface? After that, we started foundation.

Mr. Chandrakant (Engineer)




Team
CBEC India