Effectiveness of narra seed pod ash (pterocarpus indicus) as admixture in concrete paving blocks/ Reamae Z. Alega, Kenneth Jondel D. Magpantay, Mary Joy C. Maniego, Cherry Mae M. Palaje, and John Lloyd C. Torres.--

Bachelor's thesis

College of Industrial Technology.-- Bachelor of engineering technology major in construction technology: Technological University of the Philippines, 2025.

Includes bibliographic references and index.

This study explores using Narra seed pod waste as an additive in producing concrete paving
blocks, aiming to assess its potential to improve the strength and durability of concrete
paving blocks (CPB). This study is focused on designing, fabricating, testing, and
evaluating the effects of incorporating Narra seed pod ash (NSPA) in concrete paving
blocks. Different mix designs using a ratio of 1:6, with various proportions of 0%, 30%,
40%, 50%, and 60% NSPA, were incorporated into the concrete mix within the class B
mixture. The physical and mechanical properties of each CPB sample were tested based on
the ASTM standard requirement. The results in the water absorption tests show that 28-
day-cured CPB with 40% NSPA had the highest water absorption rate of 2.77, which
conformed with the ASTM C14O as it does not exceed 5%. CPB's compressive strength
test results show that 40%, 50%, and 60% NSPA surpassed the ASTM C936M standard
requirement with 3070 psi, 3133 psi, and 3295 psi. Flexural strength test results show that
60% NSPA had the highest flexural strength of 689 psi, which met ASTM C78 standards.
It indicates that a higher proportion of NSPA in the concrete paving blocks enhances their
ability to withstand compressive forces. Including NSPA has positively impacted concrete
paving blocks' compressive strength. It proves that utilizing Narra seed pod ash as an
admixture in concrete paving blocks is effective.