Increasing the strength of beach sand concrete hollow blocks

• Main Authors: Syquiatco, John Kevin S., Terrenal, Edron Benedict
• Format: text
• Language: English
• Published: Animo Repository 2006
• Subjects: Strength of materials; Hollow bricks > Testing; Civil Engineering
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/4908
• Institution: De La Salle University

The Philippines is a third-world country in need of development, and infrastructures are one of the main factors taken into consideration. With construction materials constantly improving, alternative raw materials are continuously taken into study. Concrete hollow blocks (CHB) are very popular in the Philippines as they are economical. River sand is generally used as aggregate in CHB, with it making up 90% of the CHB.;"Being an archipelago with thousands of kilometers of coastlines, beach sand is sometimes used as aggregate due to its abundance but usually result in poor quality. Steps on how to increase the strength of beach sand CHB are proposed, with samples of beach sand taken from San Fernando and Lubang Island. Compressive strength and cost are two main factors considered. Actual CHB specimens were made from sand samples taken, utilizing a molding machine with vibrator from an existing manufacturer. Different cement-aggregate ratios are used, and the grading of the sand was also investigated through sieve analysis. Ordinary blocks from river sand were also made during the same session for comparison. Higher cement-aggregate ratios increased strength, but would directly affect its cost. The grading of the sand played an important role in its compressive strength, and was examined as beach sand was poorly graded and did not conform to ASTM specifications, as opposed to river sand. Blending of aggregates for the beach sand sample was done in trial and error until it would fit into ASTM specifications, with river sand being a guide as it conforms and fits. With the steps taken and allowed, beach sand CHB strength would increase, thus making beach sand a suitable alternative. In addition, beach sand CHB are lighter, and would entail additional savings. Usage would benefit the country, and can be used for coastal area livelihood projects as well as various low-cost housing developments.