จำนวน Repository ( 8 )

การพัฒนาเถ้าแกลบและเถ้าถ่านหินเพื่อใช้แทนที่ปูนซีเมนต์ปอร์ตแลนด์ในงานคอนกรีตกำลังสูง
การพัฒนาเถ้าแกลบและเถ้าถ่านหินเพื่อใช้แทนที่ปูนซีเมนต์ปอร์ตแลนด์ในงานคอนกรีตกำลังสูง

This research presents a study of the use of classified fly ash and ground rice husk ash as a pozzolanic material in producing high-strength concrete. Portland cement (CT) is partially replaced with classified fly ash and ground rice husk ash by weight of the cementitious materials. Compressive strength porosity and chloride penetration were investigated. The results show that the compressive strength resistance to chloride and low porosity of high-strength concrete improves substantially with partial replacement of Portland cement with fly ash and rice husk ash.

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Compressive strength determination of bottom ash mixed with dust stone and portland cement
Compressive strength determination of bottom ash mixed with dust stone and portland cement

This research was to determine the appropriated mixing ratio of bottom ash and admixture (dust rock and Portland cement type 1) for improving the compressive strength. Bottom ash was used instead of soil and the quantities of admixture were 0 2 4 6 8 and 10% by dry weight of bottom ash. The specimens were cured for 7 14 28 and 90 days. Results of compressive strength test show that the admixture of 8% was the best mixing ratio. The increasing primary strength is developed from hydration reaction and the increasing secondary strength at 90 days is developed from pozzolanic reaction. Moreover the compressive strength of this specimen is close to the compressive strength of laterite

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Study on Properties of Laterite Soil Portland Cement and Slag Mix as a Pavement Materials
Study on Properties of Laterite Soil Portland Cement and Slag Mix as a Pavement Materials

This project was to study the properties of basement soil which used portland cement laterite soil and slag as the main ingredients and to investigate its appropriate ration to be used for pavement improvement. By using 95% of laterite by weight and 5% of the mixed Portland cement and slag by weight the amount of portland cement to that of slag at 5% : 0% 3.5% : 1.5% 2.5% : 2.5% 1.5% : 3.5% and 0% : 5% by weight were mixed together. Then the derived mixture was put together with the laterite which was the major material. The study showed that the ration at 3.5% of portland cement and 1.5% slag to the laterite at 95% provided the best basement soil in quality. At this ration it saved the cement content used as well. At this ration it gave soil cement higher plasticity. Its CBR is high as well. Moreover it provided the standard unconfined compressive strength according to that defined by The Department of Highway of Thailand.

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An Experimental investigation of the carbonation of blended portland cement palm oil fuel ash mortar in an indoor environment
An Experimental investigation of the carbonation of blended portland cement palm oil fuel ash mortar in an indoor environment

In this research palm oil fuel ash was utilized as a pozzolanic material in blended Portland cement mortar. The mortar was tested on the normal compressive strength and the negative effect of carbonation in indoor environment using the accelerated carbonation test of 5% CO2 in 50% relative humidity. Three palm oil fuel ash fractions of different fineness viz. coarse original palm oil fuel ash (CPOA) medium palm oil fuel ash (MPOA) and fine palm oil fuel ash (FPOA) were used for the study. Ordinary Portland cement (OPC) was partially replaced by these palm oil fuel ashes at the dosages of 20% and 40% by weight of binder. The results showed that the incorporation of the ashes affected the strength and the carbonation depths of mortars. The strengths of mortar slightly decreased with the increases in the dosage of the ash. The fineness of ash on the other hand improved the strength and the carbonation of the mortars. The mortars containing FPOA exhibited high strength and relatively low carbonation in comparison to those using coarser MPOA and CPOA. The use of FPOA resulted in a strong and dense mortar owing to the increased packing effect and pozzolanic reaction. It was therefore demonstrated that the FPOA could be used as a pozzolanic material to replace part of Portland cement for use in the indoor environment.

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Use of disposed waste ash from landfills to replace Portland cement
Use of disposed waste ash from landfills to replace Portland cement

In this study waste ash was utilized as a pozzolanic material in blended Portland cement in order to reduce negative environmental effects and landfill volume required to dispose of waste ash. The influence of waste ash namely palm oil fuel ash rice husk ash and fly ash on compressive strength and sulfate resistance in mortar were studied and evaluated by some accelerated short–term techniques in sodium sulfate solutions. Ordinary Portland cement (OPC) was partially replaced with ground palm oil fuel ash (POA) ground rice husk ash (RHA) and classified fly ash (FA). Single pozzolan and a blend of equal weight portions of POA RHA and FA were also used. The resistance to sulfate attack of mortar improves substantially with partial replacement of OPC with POA RHA and FA. The use of a blend of equal weight portions of FA and POA or RHA produced mixes with good strength and resistance to sulfate attack. POA RHA and FA have a high potential to be used as a pozzolanic material.

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