Method of Statement for Unit Masonry

Method of Statement for Unit Masonry

     1.  SUMMARY:   This method of statement includes unit masonry                               assemblies consisting of the following:

1. Concrete Masonry Unit
   1. 100mm Hollow and Solid
   1. 150mm Hollow and Solid
   1. 200mm Hollow and Solid
   1. 200mm Insulated Blocks (External wall)

B. Mortar Materials /Mix

•  Materials to be used:

                    Approved Companies:

1. Al Falwa Blocks (Transmittal Ref. No. C-1A,1B&1C-A-196)       
   1. Al namla Blocks (Transmittal Ref. No. C-1A,1B&1C-A-195)        
   1. Bin Dayal Blocks (Transmittal Ref.No. C-1A,1B&1C-C-0054)     
   1. All masonry units will be delivered to site in pallets which will be stored in elevated platform in dry location following the approved logistic plan. If stored in open place, top and sides of stacks will be covered with waterproof sheeting securely tied.
   1. Compressive Filler (Transmittal Ref.No.C-1A,1B&1C-A-0275)  (for submittal)
   1. Accessories (Transmittal Ref.No C-1A,1B&1C-A-0074)
   1. Mortar Mix: Job mix mortar should have a minimum cement to sand mix ratio of 1:3 (subject for Approval) and the strength is not less than 5 + 1N/mm. Mortar should be used within 30 minutes after mixing.

• Equipment and Tools:
• Motor-driven saws for cutting masonry units
• Water cooled saws
• Electrical grinders for cutting for embedded E/M conduits.
• Mechanical mixer machine for mortar job mix.
• Tools; wire level, plumb bob, chisel, concrete swivel, aluminum bar, steel angle 90^o/45^o/135^o, rubber hammer, brush, bucket, one wheel trolley.

• Preparation

4.1     A survey and inspection on completion of structural work for structural element recording deviations and deficiencies,          if any a complete report of each building shall be submitted to      the Engineer prior to commencing building masonry           assemblies on Foundation.

4.2     Clean the floor, under wall course of dirt using brush.           Remove any slurry, laitance, leaving a sound concrete.

4.3     Setting out for unit masonry work for each building in respect to coordinates from approved shop drawing.

• Installation

          5.1     Lay out walls for accurate spacing of surface bond patterns                          and for accurate location of openings movement type joints,              returns and offset.

                    5.2     Wet bricks before laying, allow units to absorb water so                                     they are dump but not wet at the time of laying the course.

                    5.3     Wet the floor under walls

                    5.4     For starting course on footings spread out full mortar bed,                                 including areas under cell, following the approved setting of                            walls.

                    5.5     Masonry unit will be laid with full coverage mortar on                                    horizontal and vertical shells and will maintain a joint                                       thickness of 10mm minimum and 12mm maximum for                                     joints.

                    5.6     Connection between walls and partition should be bonded,                                     tied by using wall angle to be nailed in the column before                                    the succeeding layer is laid. For a partition to be                                              connected to an adjacent wall, this will be done by toothing.

                    5.7     Submitting “Work Inspection Request” to the consultant to                                       get approval on the first course. It should be signed by all                                concerned related discipline for coordination purposes.

                    5.8     After layout approval, courses shall be laid to comply with                                 specified construction tolerances, with courses accurately                                 spaced and coordinated with other construction.  No higher                                        than six courses shall be laid in one day.

                    5.9     At stopping and resuming work in each course, rack back                                one-half running bond or one-third unit length for one third                             running bond, clean exposed surfaces of set masonry and                                 remove loose masonry units and mortar before laying fresh                                    masonry.

                    5.10   Fill cores in hollow masonry units with mortar under                                                   bearing plates, beams, lintel and post, door and window                               opening jambs.

                    5.11   Leave opening for E/M embedment and fixture after                                                   approved successful installation, complete the masonry to                                       match the adjacent wall. Opening for E/M embedment                                routing, grinder and chisel will be used.

                    5.12   Lintel beams will be casted-in-situ. Use concrete lintels                                        minimum depth 200mm for all openings in masonry                                         assemblies with 200mm minimum bearing at each jamb.

                    5.13   Install mortar in joint between top of partition and the                                   soffit after filling gap with solid piece blocks and install                                 compressible filler.    

                    5.14   Fill space between hollow metal frames and masonry solidly                             with mortar.

                    5.15   Clean unit masonry as work progresses by dry brushing to                                         remove mortar fins and smears before tooling joints.

                    5.16   Remove and replace masonry units that are loose, chipped                                     and broken. Install new units to match adjoining units with                                     fresh mortar.

                    5.17   Curing of masonry will be for 3 days by sprinkling of water                                         twice a day.

          6.0     Construction Tolerances.

                    6.1     Plumb variation for vertical lines and surfaces of columns,                                   walls, and arises should not exceed 3mm in 3m, nor 6mm                                  in 12m.                                                                                                            6.2     Variations from level for bed joints and lines of exposed                                  lintels, sills, parapets, horizontal grooves should not exceed                                 3mm in 6m, nor 6mm in 12 m.

                    6.3     Variations of Linear Building Line for columns, walls and                                  partition do not exceed 6mm in 6m, nor 10mm in 12m.                    6.4     Variations in Mortar-Joint Thickness should be 3mm with a                              maximum thickness of 12mm.