จำนวน Repository ( 61 )
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.
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
ผลิตภัณฑ์คอนกรีตบล็อกมวลเบาผสมเศษเซรามิกเหลือทิ้งจากโรงงานอุตสาหกรรมสำหรับการก่อสร้างอาคารเขียว
The objectives of this research are to study the production step proper ratio physical properties mechanical properties and thermal insulation of concrete blocks mixed with waste ceramic powder. The ratios of concrete block mixed with waste ceramic powder include Portland cement type1: quarry dust: waste ceramic powder equal to1: 6.8: 0.2 1: 6.7: 0.3 1: 6.6: 0.4 1: 6.5: 0.5 and1: 6.4: 0.6 by weight. Water per cement ratio are 0.6 by weight. The concrete block samples were castedby the general production as same as the ordinary concrete blocks and were tested follow TIS.58. From the results the best amount of waste ceramic powder which put into concrete block is 1: 6.7: 0.3 of ratio. The proper ratios of waste ceramic powder can decrease the density or weight and increase the thermal insulation efficiency of concrete blocks. However the high amounts of waste ceramic powder effect to decrease the mechanical properties concrete blocks that are lower than TIS.58 standard.
การใช้ประโยชน์จากเศษถนนยางมะตอยเก่าสำหรับผลิตภัณฑ์แผ่นกระเบื้องคอนกรีตปูพื้นที่ต้านทานแรงดัดสูงเพื่อลดผลกระทบต่อสิ่งแวดล้อม
The objective of this research is to develop the concrete flooring tile product from old asphalt road waste. The 6 ratios of Portland cement type1: coarse sand: old asphalt road waste: water reducer type A: tap water were designed including: 1: 5: 0: 0.02: 0.4 1: 4.5: 0.5: 0.02: 0.4 1: 4: 1: 0.02: 0.4 1: 3.5: 1.5: 0.02: 0.4 1: 3: 2: 0.02: 0.4 and 1: 2.5: 2.5: 0.02: 0.4 by weight. The concrete flooring tile casted with the compressive machine. The property tests followed the TIS.378 - 1988 (concrete flooring tiles). According to the result it was found that the 1: 2.5: 2.5: 0.02: 0.4 was the proper ratio of the concrete flooring tile. The increasing of old asphalt road waste in concrete flooring tile effected to decrease the water absorption and thermal conductivity properties. In term of the density and bending strength properties there were not many differences. The developed concrete flooring tile product from old asphalt road waste can use as same as the common concrete flooring tile product in market.
การใช้เศษต้นมันสำปะหลังเป็นมวลรวมน้ำหนักเบาสำหรับผลิตภัณฑ์ คอนกรีตบล็อกรับน้ำหนักประเภทควบคุมความชื้น
This research aims to develop the concrete blocks mixed with cassava pit waste. There are 6 mixing ratios among Portland cement type1: rice hush ash: quarry dust: cassava pit waste: water reducer type A: tap water that include 0.7: 0.3: 10: 0: 0.02: 0.6 0.7: 0.3: 9.9: 0.1: 0.02: 0.6 0.7: 0.3: 9.7: 0.3: 0.02: 0.6 0.7: 0.3: 9.4: 0.6: 0.02: 0.6 0.7: 0.3: 9.1: 0.9: 0.02: 0.6 and 0.7: 0.3: 8.8: 1.2: 0.02: 0.6 by weight. The concrete block samples were casted same as the ordinary concrete blocks and test were conducted according to TIS.57-1990 standard. From the results the best proportion of concrete block mixed with coconut shell ash is 0.7: 0.3: 9.7: 0.3: 0.02: 0.6. The proper ratios of cassava pit waste can decrease the density or weight and increase the thermal insulation of concrete blocks. However the over amounts of cassava pit waste that effected to increase the water absorption and decrease the compressive strength properties of concrete blocks.