This post explains the necessary Inspections and testing required for the construction of AAC blocks. The Indian standards (IS Code) related to this activity is IS 2185 Part 3 for requirements of AAC blocks and IS 6041 for code of practice for construction. This is only a summary and a full customizable ITP with the required checklist in word format can be downloaded from the link given at the bottom.
WHAT IS AAC BLOCKS
Autoclaved aerated concrete (AAC block) is a lightweight, precast, foam concrete building material suitable for producing concrete masonry unit (CMU) like blocks. Composed of quartz sand, calcined gypsum, lime, cement, water and aluminum powder, AAC products are cured under heat and pressure in an autoclave. (Reference Wikipedia). Due to its incredible stability and other constructive properties AAC block works are more common with not only builders but acceptable to architects also as they have much more freedom than other conventional methods. This post explains the method of construction to be followed in the site for AAC Block work.
WHAT IS AN INSPECTION AND TEST PLAN OR ITP
Inspection and Test plans and checklists are integral parts of quality management systems not only in construction but in almost every industry where Quality Management systems are in place. It is considered to be master documents through which different parameters and actions of a process or activity would be monitored and recorded which play a vital part during the verification later or in simple terms during auditing.
In the construction industry, where there are a lot of activities, for a variety of trades such as structural, Finishes, Façade, Electrical, Mechanical, Plumbing, etc. are to be completed spanning across excavation for the foundation to handing over the stage, thereby Preparation and implementation of different inspection test plans form the most crucial part of the project management system.
To read more about ITP and how to prepare one CLICK HERE and refer to the last picture in this post to get a quick understanding of ITP’s structure and how to structure it as per the project requirements
Inspection and Test Plan For AAC Block Works
SECTION 1 – DOCUMENTATION REVIEW
This part deals with the review and approval requirements of necessary documents needed to be completed before the work on-site is to be started. The important part is drawings including the typical details common to all the work in different areas and sections, materials (Blocks, cement, sand, metal laths, or accessories) as detailed in the project specifications or the standards mentioned in the contract,
The sampling and testing of blocks also mentined in detail in IS 2185 Part 3. Apart from these, Method statements also become part of the documentation.
SECTION 2 – SAMPLE APPROVALS
The sample of AAC blocks with all necessary test details are to be submitted to the concerned authorities for approval based on the project specifications. Also, details of other ingredients such as ready-mix mortars, accessories, cement sand also submitted.
SECTION 3 – INSPECTION OF INCOMING MATERIALS
This part deals with the inspection of materials procuring for the AAC block works based on the approved material details. The storage of materials also shall be checked whether it is followed the guidelines or standards applicable.
SECTION 4 – PRE WORK INSPECTION (INSPECTION PRIOR TO START OF BLOCK WORKS)
Pre-work inspection is important for any activity. Some project owners or consultants will insist to make a sample of work with the approved AAC blocks to ascertain the quality of work. The workmanship, the finish, etc will be assessed before proceeding with the work on site. Once the sample is approved it shall be kept as a reference and will be marked for the same.
A review of the structure where AAC block works are to be started to be done whether it is cleared for proceeding with the architectural works. Chances are there to have some open NCRs in locations where block works come.
The important inspection points are
| Mockup (Sample) wall construction |
| Check on area |
| Check for surface preparation |
| Check on setting out |
| Check on the first layer of Blockwork |
| Check on scaffoldings |
SECTION 5 – WOK IN PROGRESS INSPECTION
This part deals with the points to be taken care of while the construction of AAC blocks is in progress. Some inspection points may not be on “HOLD’ during this stage and hence keen attention is required during routine site visits (SURVEILLANCE). When discrepancies/changes against the acceptance criteria are observed instruction to be given to rectify them immediately.
The major points are
| Check for mixing of mortar and check for consistency |
| Check on use of mixed mortar |
| Check during subsequent laying |
| Fixing of Dowels, Embedment |
| Check for cut pieces |
| Check on joints |
| Check on vertical joints on subsequent layers |
| Check for walls coming in contact with concrete surfaces |
| Check for maximum height of construction per day |
| Check for Lintels and bond beams |
SECTION 5 – POST WORK INSPECTIONS
The constructed AAC Block works shall remain true as per the approved drawing. It shall be true to the line, length, and square. As per IS standard curing does not require on AAC Blocks. Cutting nad chasing may not be allowed until the block works are accepted.
Refer to the picture at last to learn tips on How to Customize the ITP based on Project Requirements
Download full customizable ITP for AAC Block Works
QUICK LEARNING ON ITP AND ITS CONTENTS
Leave a Reply