ByMd. Hachnayen Ahmed

10106063BSCE

CONCRETE STRUCTURES QUALITY CONTROL IN PRACTICE

OBJECTIVES

Introducing the main causes of deterioration of concrete structure in Bangladesh

Show the concept and tools that are available to us

Show the necessasity of Contractor and Engineering plan prior to starting the works.

CONCRETE BASICS

Portland Cement Aggregates (both fine &

Coarse) Water

CAUSES OF DETERIORATION Exposed to Weathering Exposed to Environment(e.g. parking garage, exterior balcony slab etcetera) Chemical reaction within

the cement matrix, aggregate and moisture

Fire, because of shock heating

LEGAL FRAMWORK

Planning and preparation of the entire process Scaffolding Formwork Reinforcement Concrete casting Care and Protection

CAUSES EARLY DETERIORATION OF CONCRETE IN BANGLADESH Un-Sieved Aggregates Un-Washed Aggregates Overly wet sand Mud water for mixing Rusted reinforcement Excess water in mix Excess fine aggregates Poor mixing ratio Lack of cover concrete Placing of concrete from a

large height by labor Brick efflorescence

CONTROCTORS QUALITY CONTROL PLAN

Appoint a responsible person Ensure the expertise , experience, independece

and impartiality of responsible person Submit a rough concrete design

The Contractor's documentation procedures will be subject to approval of the Engineer before the start of the work and to compliance checks during the progress of the work.

CONCRETE CONSTRUCTION ENGINEER

Ensure or prepare correct and detailed design documentation.

Documentation include the quality and reliable performance

Design the technical documentation (site use only)

Preparatory work (planning) Scraffolding and form work (before and after

casting)

QUALITY CONCRETE PREPARATION

Quality control procedures implement appropriate mixing, proper compaction, correct placement and adequate curing.

Quality control prevents temptation of over design

Quality control ensures strict monitoring of every stage of concrete production and rectification of faults. Quality control reduces maintenance costs.

CONCRETE WORK PERFORMANCE

Quality system in this process includes the following activities: Analysis of the project documents developing the concrete structures quality

performance plan Erection of scaffolding and formwork Casting and compaction of concrete Proper Curing of Concrete Cultivation and protection of concrete Actions to be carried out after the casting

ERRORS AND IMPROVEMENTS

• During the execution of concrete construction, errors occur at all stages. In order to eliminate errors it is necessary to perform the following:

A detailed study of project documentation Aligning of the potential doubts before the start of

concrete works Quality assurance performance of reinforced

concrete structures Document and define all activities within the

process It is necessary to hire professional

ERRORS AND IMPROVEMENTS

Planning and providing training for all the participants whose work affects quality

Defining a procedure to eliminate non-compliance performance

Creating a concrete quality performance plan that will elaborate the performance of the construction in accordance with the available resources and organizations.

CONCLUSION

• Causes for poor quality can be summarized as ignorance, poor materials, poor design, poor detailing, and poor workmanship, improper quantity of cement, improper concrete mix, excess water, inadequate compaction, substandard forms, inadequate curing, inadequate cover etc and above all the lack of technical knowledge.

For your time and attentation

Any Questions ?