จำนวน Repository ( 1174 )
คุณสมบัติเชิงกลของคอนกรีตมวลเบาผสมวัสดุปอซโซลาน
This research study the effect of pozzolanic materials on light weight concrete by replacement cement with fly ash and Meta kaolin which affect the properties of concrete by using pumics aggregate. Coarse in aerated concrete and consider mechanical properties. Aerated concrete replacement cement by fly ash 20% 35% and 50% respectively and meta-kaolin is replaced. From the results it was found that the compressive strength of light weight concrete at 28 days w/b = 0.55 was higher than that of every 14 days of cement and cement cement replacement by fly ash 50% highest value compressive strength. More than all the ingredients replaced with fly ash and Meta kaolin. When considering the flexural strength of replacement cement with 10% by Meta kaolin the maximum flexural strength of 80 ksc was higher than that of control concrete and all other ingradient. Experimental tensile strength at 28 days result found that replacement cement by fly ash at 35% gave the highest tensile strength of 28 ksc and gave higher tensile strength than all other ingradient. From the impact strength test at age 28 days it was found that the replacement cement 35% by fly ash gave the highest impact strength of 92.00 joule than the 20% and 50% respectively and higher impact strength than that of all kaolin. Except for control concrete.
การรับแรงกระแทกของคอนกรีตผสมปอซโซลานโดยระบบสามประสาน
This research study to the effect of pozzolanic materials by replacement cement by fly ash and Meta kaolin which affect the mechanical and physical properties of concrete. According to Standard test such as Compressive strength flexural strength and impact strength. The replacement cement by fly ash was 15% 30% and 45% respectively and replacement cement by meta-kaolin was 10% 15% and 20% respectively. The results showed that the compressive strength of concrete at 28 days. When considered ratio w/b = 0.40 was higher than w/b = 0.45 all ingredient. The replacement cement by fly ash was the most effective. 10% (375 ksc) 15% (362 ksc) and 20% (354 ksc) respectively. The replacement cement by meta-kaolin gave the highest flexural strength of 41 ksc higher than control mixed concrete and all other ingredient. At the age of 28 days The replacement cement by meta-kaolin was 10 percent result to the highest impact strength was 11 joule which was close to that of fly ash by 30 percent give value was 110 joules and more than replacement cement by meta-kaolin was 15% (100 joule) and 20% (95 joule). It can be concluded that the increase in meta-kaolin content result to compressive strength will reduce flexural strength and impact strength. As the amount of fly ash increased the compressive strength increased. flexural strength and impact strength Increased value.
การศึกษาตัวแปรที่มีผลต่อสมรรถนะการฉีดเชื้อเพลิงของหัวฉีดรถยนต์ที่ใช้น้ำมัน ไบโอดีเซล และ น้ำมันไพโรไลซิส
The purpose of this research is to study on variables affecting fuel injection performance of biodiesel fuel injection and pyrolysis fuel. To test for variables affecting the fuel injection performance of biodiesel fuel injectors and pyrolysis fuel. By experimenting and modeling using computer programs to compare results. Finally for to use the information in the design of the car nozzle to work well with Biodiesel and pyrolysis fuel. The tested fuels which are pyrolysis fuel Bio-diesel fuel and diesel fuel are tested by tester Anton Paar@ Stabinger Viscosmeter (model SVM 3000/G2) ASTM D341 standard. The result shown that the density of the fuel is increasing normally. However the viscosity of the diesel and biodiesel are strong increased whereas the reducing of temperature is unaffected to the pyrolysis fuel. The fuel injection performance test showed that the density and viscosity of fuel were the major variables that affected the injection performance of the fuel. In case of using pyrolysis oil Injection performance is trend to higher other fuels and cold conditions.
พฤติกรรมการมีส่วนร่วมในการประหยัดพลังงานไฟฟ้าของนักศึกษา ระดับปริญญาตรี คณะวิทยาศาสตร์และเทคโนโลยี มหาวิทยาลัยเทคโนโลยีราชมงคลพระนคร
This research was aimed to study the participation behaviors in the electrical energy saving the factors affected to the participation behaviors and the promotion of the participation behaviors in electrical energy saving of the undergraduate students of the Faculty of Science and Technology Rajamangala University of Technology Phra NaKhon. The participants of 150 students from the Faculty of Science and Technology was also performed based on systematic sampling. The questionnaire was used. The statistical evaluation was also analyzed based on the percentage mean and standard deviation. A 85% of participants is male a range of age to be 19-20 years old (62.7%) second academic years by about 37.3% and a 65.3% of participants has been studying in the major of computer science. Knowledge levels in the electrical energy saving of the most participants are high (13.33%) moderate (62%) and low level (24.67%). The four participation behaviors in the electrical energy saving were analyzed including electrical lighting system air conditioner and ventilator system office electrical system and electrical equipment maintenances resulting in very high level with the average mean of 4.25 and standard deviation of .547. First the participation behavior in the electrical equipment maintenance was very high level with 4.31 and S.D.=.870. Second the participation behavior in the office electrical system was to be 4.27 with S.D.=.828. Third the participation behavior in the air conditioner and ventilator system was to be 4.21 with S.D.=.549. Finally the participation behavior in the electrical lighting system was very slow level with 4.21 and S.D.=.672. By comparing the participation behaviors in the electrical energy saving with the different of academic major of students the participation behaviors in the electrical energy saving did not significant different.
ผลิตภาพแรงงานของงานฉาบปูนผนังภายในอาคาร
The purpose of this research was to study productivity rate in concrete plastering of interior brick wall by studying 2 construction projects in Bangkok. The researcher divided the methods of labor productivity into two categories: (1) direct labor production technique and (2) field rating technique. The direct labor productivity technique of project A is about 1.38 m2/person/hr. and project B is about 1.19 m2/person/hr. by field rating technique project A had 77.75 % of workers in work status project B had 73.75% of workers in work status. The error rate was 4.08 % and 4.31 % respectively at the 95% confidence level. Project A has higher productivity rate than project B because project manager A chooses ready-mixed plaster for plastering. Project B selects cement mix (silica cement) mixed with fine sand cement mixer and water which take longer to prepare than Project A resulted cost of materials increase for 28.21 %.Meanwhile the working time for wall plastering could take longer for 13.77 %. It can be concluded that the selection of material for work is another factor affecting labor productivity