Utilization of Carbonized Rice Hull, Rice Hull Ash and Lahar as Raw Materials in the Production of Lightweight Hollowblocks
Chapter I
Introduction
A. Background of the Study Hollow blocks are one of the most used building materials in our time. Since hollow blocks weigh around 9-11 kg, it is a must for reinforcement steel to be placed into the gaps of the hollow blocks and/or to be built on a strong foundation in order to avoid settling or cracking. A higher capital is needed for a strong foundation that can hold the weight of standard concrete hollow blocks (esp. for high and large buildings). The heavier the hollow blocks, the greater the force exerted to lift them. This may lead to problems like back pains, abrasions, muscle pains and the like. Therefore, hollow blocks must be lighter. Light aggregates must be used like lahar, carbonized rice hull and rice hull ash. Lahars come mostly from volcanic activities (like the Mt. Pinatubo explosion). It is a type of mudflow or debris flow that slides along the volcano that can run as fast as 40 m/s. Lahar is a possible component in road construction according to the study of Reynaldo P. Faustino, Nenita R. Valencia, Michael J. O’Connell and William Ford entitled, “Making Effective Use of Volcanic Ash [lahar] in Road Building in the Philippines”. It resembles coarse sand (but has a grayish color). It is an effective replacement for coarse sand that may contribute to the enhancement or maintenance of the durability of a hollow block. It can also lessen water absorbency without affecting the concrete’s strength. It is also widely used as a source of fine aggregates in the building industry, as sculpture materials, as decorations, hollow blocks, etc. (Source: http://answers.yahoo.com/question/index?qid=20070925231551AA34tSU )
Carbonized Rice Hulls (CRH) are black and often in the shape of the raw rice hulls. It can enhance the strength of concrete mixes up to 5% (http://brushenvironment.webs.com). On the other hand, Rice Hull Ash (RHA) is white and has very small particle size (25 microns) compared to cement (35 microns) that can contribute
Introduction
A. Background of the Study Hollow blocks are one of the most used building materials in our time. Since hollow blocks weigh around 9-11 kg, it is a must for reinforcement steel to be placed into the gaps of the hollow blocks and/or to be built on a strong foundation in order to avoid settling or cracking. A higher capital is needed for a strong foundation that can hold the weight of standard concrete hollow blocks (esp. for high and large buildings). The heavier the hollow blocks, the greater the force exerted to lift them. This may lead to problems like back pains, abrasions, muscle pains and the like. Therefore, hollow blocks must be lighter. Light aggregates must be used like lahar, carbonized rice hull and rice hull ash. Lahars come mostly from volcanic activities (like the Mt. Pinatubo explosion). It is a type of mudflow or debris flow that slides along the volcano that can run as fast as 40 m/s. Lahar is a possible component in road construction according to the study of Reynaldo P. Faustino, Nenita R. Valencia, Michael J. O’Connell and William Ford entitled, “Making Effective Use of Volcanic Ash [lahar] in Road Building in the Philippines”. It resembles coarse sand (but has a grayish color). It is an effective replacement for coarse sand that may contribute to the enhancement or maintenance of the durability of a hollow block. It can also lessen water absorbency without affecting the concrete’s strength. It is also widely used as a source of fine aggregates in the building industry, as sculpture materials, as decorations, hollow blocks, etc. (Source: http://answers.yahoo.com/question/index?qid=20070925231551AA34tSU )
Carbonized Rice Hulls (CRH) are black and often in the shape of the raw rice hulls. It can enhance the strength of concrete mixes up to 5% (http://brushenvironment.webs.com). On the other hand, Rice Hull Ash (RHA) is white and has very small particle size (25 microns) compared to cement (35 microns) that can contribute