Quality Control Procedures in Construction

Study Notes

Quality Control

Quality control is a customer-centric approach, measuring how well a product or service meets needs and expectations.
Quality control is a process of regulation, ensuring economical work, safety, and aesthetic appeal.
Quality control work is done by managers and their teams, contributing to the quality of the organization's output.

Quality Control Procedures

Material Selection:
- Raw Materials: Sources of materials like soil, sand, and gravel are to be identified.
- Processed Materials: Consideration given to materials that have undergone changes, such as washed sand, crushed rock, and gravel.
- Manufactured Materials: Attention to materials created through a manufacturing process, including bituminous materials, cement, paint, and structural reinforcing steel bar.
- Combinations: Assessment of materials that are partly or fully manufactured, such as concrete solutions.
Materials Handling and Storage:
- Proper handling procedures are critical to prevent damage and ensure materials remain in good condition.
- Secure storage is crucial to avoid contamination by water, which can cause corrosion in steel and hardening in cement.
Sampling and Testing:
- All materials for testing require proper sampling techniques, as outlined by AASHTO and ASTM standards.
- Quality control includes comprehensive testing of materials, considering construction methods and workmanship.
Minimum Testing Requirements:
- The program of works details the minimum testing requirements for each project, specifying types and number of tests for each item.
- While this provides minimum guidelines, additional testing may be required based on project specifics.
- Government representatives can demand additional testing if concerns arise.
Construction Methods:
- Construction methods vary, relying on experience and technical guidance.
- Project management should include:
  - Knowledgeable and responsible personnel.
  - Clear project supervision hierarchy.
  - Implementation of construction methods as detailed in the design.
  - Materials conforming to specifications.
  - Consistent quality control throughout construction.
  - Use of suitable equipment for each work item.
  - Adequate material supply to avoid delays.
Inspection and Project Monitoring:
- Project inspection is crucial for monitoring progress, with regular reports encompassing actual work being carried out and weekly accomplishments.
- The goal is to ensure adherence to standards, with inspections focused on materials and workmanship.

Quality Control in Earth Road, Embankment, Subbase, and Base Course

Pavement Structure:
- Subgrade:
  - Removal of unsuitable materials from cut sections and replacement with selected fill.
  - Rejection of unsuitable material for embankments or use in lower layers.
  - Comprehensive surface and subsoil drainage.
  - Minimizing moisture content variations.
  - Thorough compaction based on material requirements.
- Subbase Course Material:
  - Subbase provides a layer of aggregate material on the subgrade, supporting the base course.
  - Vital for pavements with vehicle traffic but not required solely for foot traffic.