Kesan penggunaan abu bahan api sisa sawit terawat (TPOFA) terhadap sifat-sifat reologi dan turap simen semasa keras telah dikaji. POFA yang diperolehi daripada kilang kelapa sawit dirawat dengan cara mengisar dan proses pembakaran untuk menghasilkan TPOFA. TPOFA tersebut digunakan untuk menghasilkan campuran asas turap simen yang boleh disuntik melalui kaedah penggantian simen sebanyak 0%, 10%, 20%, dan 30% daripada berat simen tersebut untuk menyelesaikan kehadiran rongga kosong kesan daripada turapan tidak sempurna. Sebanyak 0.46 nisbah simen terhadap bahan pengikat digunakan terhadap semua campuran turap simen. Penggunaan 1% superplasticizer diperlukan untuk mencapai sifat kebelandiran yang sesuai pada kandungan POFA yang tinggi. Hasil ujian menunjukkan penggunaan TPOFA mengurangkan kadar air yang terhasil pada permukaan begitu juga kebelandiran selain daripada mengurangkan kesan perubahan isipadu terhadap turap simen yang baru di bancuh. Penggunaan TPOFA juga mengurangkan kesan terhadap nisbah pemendapan. Kekuatan turap simen yang mengandungi TPOFA pada umur 28 hari dibandingkan dengan simen Portland biasa kecuali untuk turap simen yang mengandungi 30% POFA. Walau bagaimanapun, ia mengurangkan kekuatan awal turap simen pada umur 3 hari. Peratusan keliangan untuk bahan simen itu sendiri dan semasa applikasi menurap sebenar juga berkurang. Perkara ini telah dibuktikan dengan melakukan proses menurap menggunakan kaedah suntikan di makmal. Berdasarkan keputusan yang diperolehi, dirumuskan bahawa jumlah POFA yang optimum untuk digunakan bagi menghasilkan turap simen adalah sebanyak 20% tahap penggantian.
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The effect of Treated Palm Oil Fuel Ash (TPOFA) on the rheological and hardened properties of cement grout has been investigated. POFA obtained from a palm-oil mill was treated via grinding and heat treatment processes to obtain TPOFA. The TPOFA obtained was then utilized in the production of injectable POFA based cementitious grout with POFA replacement levels of 0%, 10%, 20% and 30% by mass of ordinary Portland cement to solve the presence of voids due to uncompleted grouting. A water to cementitious material ratio of 0.46 was used for all cement grout mixtures. The utilization of about 1% superplasticizer was required to achieve suitable fluidity at higher POFA content. The test results indicate that the utilization of TPOFA decreased the bleeding rate as well as fluidity besides reducing the volume change effect to freshly mixed grout. The utilization of TPOFA also reduced the effect on sedimentation ratio. The compressive strengths of cement grout containing TPOFA at 28 days were comparable with the ordinary Portland cement grout except for grout containing 30% POFA. However, it reduced the early strength of POFA cement grout at 3 days. The percentage of porosity for material itself and during actual grouting application was also reduced with the inclusion of POFA. This had been proven by conducting a simple grouting process by injection method in the laboratory. Based on the result obtained it was concluded that the optimum amount of POFA to be used in production of POFA based cementitious grout was at 20% replacement level.
Palm oil fuel ash based cementitious grout for grouting application in precast concrete industry / Mohammad Farhan Mohammad Noor