Methodology for CHB Laying
• The initial activity shall involve all preparatory requirements such as conducting trial mixes for the mortar and concrete infill mixes including the testing of all the required components.
• Once all the preparatory works have been complied with the approved by the ClientName/ConsultantName the primary/initial phase of the work shall commence.
• Lay out of the work shall be conducted by the Survey Team in coordination with the Field Engineer in charge of the process as per approved shop drawings. Inspection will be submitted prior to the execution of work.
• Upon delivery of the material, necessary checking and test verification shall be conducted to ensure that materials delivered to site conforms to the required standards as set forth in this particular process. Batch delivery (CHB) should have a record of the date of production and design strength of these is recorded in the delivery.
• Experienced masons or block layers shall be employed in the work to achieve the required finish for the works.
• Prior to the start of block laying works, drilling in of holes for starter bars and dowels for any specified reinforcement shall be finished and checked by the field engineer in charge of the particular work. All relevant records for the earlier construction activities and all remedial works shall be complete. Concrete filler it’s either cast in place or pre-moulded.
• Dowel bars must also installed every 3 layers for horizontal reinforcement embedded columns to columns.
• Polyurethane elastic sealant must install with backing rod upon execution of the work.
• Material to be used for fixing rebar’s shall be approved and application to be witnessed by the client’s representative.
• Surface of the foundation will be scabbed before receiving the first mortar bed. CHB will be cut using powered tools and will be pre-moistened before use.
• After the first lines of block are laid, a double check shall be conducted to ensure that the location, level and alignment of the blocks is in accordance with the plan. Prior to start of activities a mock-up should be done first for inspection and approval of client representative.
• Cavities/core shall be filled with concrete as required by drawings/specification. (full grout)
• Lintels shall be constructed to support block work over opening as required by drawings/specifications.
• Client representative to check plumbness and alignment of prior to plaster application to both sides of wall.
• All block works shall be separated from structural steel members by joints according to drawings.
Methodology for Plastering
• For finishing of wall surface it is necessary the use of scaffolds, so covering works with mortar can be made at the entire height of elements.
• It starts from the upper part and then run down to the lower part, the mix in volume has a proportion of 1 of cement to 3 of fine sand.
• In columns or concrete elements should be made small picking in order to obtain a better adherence of the mortar to the element.
• To check the level surface are used metallic and / or wood squares (angles).
• Cement in bags 40 kgs must be protected from humidity so it will not harden before its use. Sand (fine sand) should not contain earth soil or any organic materials. Water should not contain filthy elements, should be clean and fresh.
• Mixing mortar, wear eye protection. Prepare the ground, clean without rubbish neither organic material nor any odd elements. Train skilled workers in the safe used of hazardous substances.
• Prior to plastering, ContractorName and ClientName representatives will conduct joint inspections for approval.
• Provide cube samples for compressive test, approved mix design must reach the required strength 3000psi at 28 days.
• Plaster must be mixed properly & must refrain from applying pure cement to avoid cracks.
• In case of cracks, chip area depending on the actual & concrete epoxy must be applied before plastering.
• Water curing for 7 days.