Quality Evaluation of Concrete Blocks Produced in Local Factories in Bangkok and Vicinity

Abstract

The construction industry in Thailand has shown a consistent upward trend in growth statistics. In 2022, the total growth rate reached 5%, highlighting the significant role of construction materials in the country’s economy. In addition to primary materials such as stone, cement, and sand, masonry materials are essential in construction, offering a range of options suited for specific applications. Among these, concrete blocks are widely used due to their cost-effectiveness, quick installation process, and reduced labor expenses. As a result, concrete blocks have become a popular material choice. However, non-load-bearing concrete blocks produced by many local factories have not been tested and certified.

This study aims to investigate production standards and the key factors influencing the quality of non-load-bearing concrete blocks by conducting field research to collect data from 2 local factories in Bangkok and its vicinity. These factories produce concrete blocks that have not been qualified for the Thai Industrial Standards (TIS). Data collection involved on-site observations of the production line, followed by laboratory testing. A total of 60 concrete block samples, 20 from each factory, were tested at the Department of Civil Engineering, Faculty of Engineering, King Mongkut’s Institute of Technology Ladkrabang. The test results were analyzed to assess compliance with the TIS 58-2533 standard, which specifies the requirements for non-load-bearing concrete blocks.

The findings indicated that, on average, the concrete blocks failed to meet the standard requirements for both dimensional accuracy and compressive strength. However, they did comply with the standard for moisture absorption. The dimensional measurements, specifically thickness, height, and length, were consistently below the standard thresholds. Similarly, the average compressive strength values did not meet the specifications outlined in TIS 58-2533. The primary factor affecting the quality of the concrete blocks was identified as inadequate control over the mix proportioning process.

This study provides insights into the deficiencies in local manufacturing practices and serves as a guideline for improving production processes to elevate the concrete blocks to meet the specified standards.