This article is about PROCEDURE FOR PROPOSED BACKFILL WORKS and focusing to the engineers, technicians and supervisors. You will find lot of documents related to this article. Just navigate our website www.paktechpoint.com and find more articles. Please! Do not forget to subscribe our You tube channel also. Thanks in Advance.
PLEASE SUBSCRIBE OUR PAKTECHPOINT YOUTUBE CHANNEL
PROCEDURE FOR PROPOSED BACKFILL WORKS
Backfill and Compaction
Backfilling will be carried out by following the norms as set out here under column:
Backfilling will be done only after the curing time for the cast-in-situ concrete is completed, surface preparation and water proofing done to concrete below ground level. Backfilling will be done using appropriate material or selected granular material when required, in uniform horizontal layers not exceeding 200 mm loose thickness. Each layer will be compacted to a dry density, depending on the area of working. When granularmaterial is used, it will be compacted to a firm and stable condition using an appropriate compacting device. Backfill material shall conform to relevant Project Specification.
Backfilling will proceed symmetrically around the structure, whenever possible to do so. Backfill around concrete structure not to be started until concrete repair works are completed and specified coatings are applied and fully cured on the concrete surface.
The water for the compaction will be sprayed uniformly. If required, the fill material will be ploughed to uniform water content before compacting. If drying is required, the same will be done by way of natural drying. In case additional dry material is added for drying,care will be taken to see that the layer thickness does not exceed as specified.
Please read also: HOW TO DO OF SHEET PILE WORK FOR DEEP PIT -CIVIL
Please read also: PROCEDURE FOR SHEET PILE DRIVING WORKS -CIVIL
Please read also: Procedure for REINFORCED MASS CONCRETE -CIVIL
Work Procedure back fill Layer
Procedure 1:
The backfill material is spread to a loose depth of the backfill layer is 350 / 300 mm (Select fill / clean sand) and after compaction the final thickness shall be 300mm. No compaction test in case of clean sand as backfill material.
Procedure 2:
The backfill material is spread to a loose depth of first layer 350 / 300 mm ( Select fill / Cleans sand)withcompactionby water flooding and internal inspection only followed by laying backfill material for second layer of thickness 350 / 300 mm ( Select fill / clean sand) with compaction by water flooding and final inspection by the client. No compaction test in case of clean sand as backfill material.
Procedure 1:
A. Procedure for backfill using select fill material
• Subgrade is prepared for the proposed back fill area.
• FDT is conducted at the required number of points and results are reviewed and submitted for approval.
• Using back hoe select fill back fill material is spread in layer of loose depth of 350mm.
• Water is spread saturating the layer.
• Compaction is carried out using 1 / 3 ton roller compactor, plate compactor and Rammer.
• After compaction the compacted backfill layer should be 300mm.
• FDT is conducted by third party technician.
• Results are reviewed and submitted for approval.
B. Procedure for backfill using clean sand
• Subgrade is prepared for the proposed back fill area.
• FDT is conducted for subgrade only for the required number of points and results are reviewed and submitted for approval.
• Using back hoe clean sand is spread in layer of loose depth of 300mm.
• Water is spread well saturating the layer.
• Compaction is carried out using 1 / 3 ton roller compactor, plate compactor and Rammer.
• After water compaction, the compacted backfill layer should be 300mm. No compaction test.
• Same procedure shall be adopted for sand bedding for underground piping works and as well as forother back fill works in other areas under the limits of without compaction test.
Procedure 2:
A. Procedure for back fill using select fill material
• Sub grade is prepared for the proposed back fill area.
• FDT is conducted at the required number of points and results are reviewed and submitted for approval.
• Using back hoe select fill is spread in layer of loose depth of 350 mm.
• Water is spread saturating the layer.
• Compaction is carried out using 1 / 3 ton roller compactor, plate compactor and Rammer.
• After compaction the compacted back fill layer should be 300 mm.
• Internal FDT is conducted for the first layer by third party technician.
• The second layer of 350 mm back fill material is spread and water is uniformly spread
• Compaction is carried out using 1 / 3 roller compactor.
• After compaction the compacted back fill layer shall be 300 mm.
• FDT is conducted by third party technician in the presence of the client
• Results are reviewed and submitted for approval.
• The same procedure is continued on the subsequent layers.
B. Procedure for backfill using clean sand
• Subgrade is prepared for the proposed back fill area.
• FDT is conducted at the required number of points and results are reviewed and submitted for approval.
• Using back hoe / Bob CAT clean sand is spread in layer of loose depth of 300mm.
• Water is spread saturating the layer.
• Compaction is carried out using 1 / 3 ton roller compactor, plate compactor and Rammer.
• After compaction the compacted backfill layer should be 300mm without any compaction test.
• The second layer of 300mm clean sand is spread and water is uniformly spread to saturate the layer.
• Compaction is carried out using 1 / 3 ton roller compactor, plate compactor and rammer.
• After compaction the compacted backfill layer shall be 300mm without any compaction test.
• The same procedure is continued on the subsequent layers.
EQUIPMENT AND TOOLS
• Excavator
• Long arm Excavator
• JCB Back Hoe
• Bobcat
• Dump truck
• Vibrating roller compactor 1 / 3 ton
• Vibrating plate compactor
• Rammer
• Water Truck
• Fuel Tank
• Wheel barrows and hand shovels
SAFETY CONTROL FOR PROPOSED BACKFILL WORKS
Contractor Safety officers shall carry out the safety site inspections to ensure that safety requirements laid out in the safe work plan are being followed during and after the excavation work. Safety Manager / Supervisor shall review Safety Action Plan and secure Work Permit if necessary prior to start of any activities job safe analysis will be strictly followed.
Barricading of excavation and “swing” areas of equipment shall be checked prior to the commencement of work.
Equipment, tools and materials inspection:
All equipment for excavation works shall have to be inspected by Safety Manager / Supervisor prior to
forwarding to contractor Safety Department inspection prior to its use at site to ensure safe worthiness
at work. The compactors likewise shall have to be checked by Safety Manager / Supervisor prior to
their use on site and during the execution of work. The inspection Reports shall be kept for record.
TSTI
Prior to work commencing, TSTI shall be conducted by the Foreman / supervisor. Review and
comments to be generated by contractor civil supervisor and safety supervisor to carry through safe
practice.
Persons involved in Excavation work shall be provided with and use the necessary PPE and as a
standard each person shall wear a Safety Helmet and Safety footwear. The requirement for additional
PPE shall be identified may include the use of the following:
• Eye protection.
• Hand Protection.
• Dust masks.
• Reflective jackets if working in the vicinity of moving traffic.
• And any other necessary PPE