จำนวน Repository ( 4 )

อิทธิพลของคุณสมบัติเชิงกลของใยสังเคราะห์ต่อคานปอซโซลานคอนกรีต
อิทธิพลของคุณสมบัติเชิงกลของใยสังเคราะห์ต่อคานปอซโซลานคอนกรีต

This research aims to study the possibility of steel fibers plastic fiber (polypropylene) fly ash and metakaolin mixed into the concrete. The concrete used in the research of the w / c 0.42 By 0.5 percent in the volume of steel fiber and poly propylene fiber in the amount of 0.25 percent by weight of the concrete. Concrete example of this test consisted of plain concrete(OPC).Concrete mixing materials pozzolan fly ash mixed plastics synthetic fibers of the type poly propylene fiber(FA/PP)concrete mixing materials pozzolan fly ash mixed plastics synthetic fibers of the type steel fibers (FA/ST) concrete mixing materials pozzolan meta kaolin mixed plastics synthetic fibers of kind polypropylene fiber(MK/PP) and concrete mixing materials pozzolan meta kaolin mixed plastics synthetic fibers of the typesteel fibers (MK/ST) by casting a cylindrical sample size 10 x 20 cm. Sample size 10x10x10 cm. cube and sample size 10x10x35 cm. beam. After 28 days and cure water concrete examples to test the strength of the pull compressive strength and flexural strength. And to test the movement of chloride through the concrete with Chloride Migration Test. Then bring the strength of the pull compressive strength flexural strength and the chloride permeability of concrete. Bringing concrete materials pozzolan mixed with synthetic fibers to develop the quality of concrete with improved efficiency and also reduces the porosity of the concrete. And permeability of chloride formed in the concrete (Only in landscape with the sea). The test can tell. Concrete mixing materials pozzolan with synthetic fibers to make a significant impact on the properties of concrete is improved as well. Depending on the type of polyester and the amount of material to pozzolan blended.

2562
การปรับปรุงประสิทธิภาพการผลิตชุดหมีทนไฟด้วยเทคนิค การจัดสมดุลสายการผลิต กรณีศึกษา : บริษัท ครีเอทีฟโพลิเมอร์ส จากัด
การปรับปรุงประสิทธิภาพการผลิตชุดหมีทนไฟด้วยเทคนิค การจัดสมดุลสายการผลิต กรณีศึกษา : บริษัท ครีเอทีฟโพลิเมอร์ส จากัด

The purpose of this research were to 1) study the production factors and efficiency of fireproof suit; 2) analyze the three line balancing models of fireproof suit; and 3) make comparison of production efficiency for fireproof suit’s manufacturing processes. A group of representative sample for assessments is 90 dressmakers of Creative Polymers Co. Ltd. The used tool for collecting data is the data recoding form consisting of production process list data recording date processing operation and duration of processing. Accordingly put the sewing line layout and make production test with the three line balancing models of fireproof suit then record all data and entry all data to SPSS program to average statistics on percentage and standard deviation. The research showed that the improvement of the three line processing models of fireproof suit comparing to the data of the three line balancing models are identified that C model increased from traditional production system 74.05 percentage B model increased from traditional production system 57.51 percentage then A model increased from traditional production system 48.53 percentage. The result showed that the fireproof suit’s production processing of Creative Polymers Co. Ltd. ought to take the C model in order to fasten production process and augment better quality. A minimum process of producing is amount of 110 steps with less time per one unit; minimum 177.41 minutes; with 30 workers; and 27 machines. The waste product of the three line processing models: A B and C model; not over 20 percentage during 8 hours of working. It shows that the c model has the least of waste product. The over operation that product has not much wasted not include in choosing the model for improving production efficiency and C model

2561
Flexural performance of corroded reinforced concrete beams repaired with CFRP sheets
Flexural performance of corroded reinforced concrete beams repaired with CFRP sheets

Corrosion of steel reinforcements in concrete is one of the main causes of early deterioration and reduction of service loads of reinforced concrete (RC) structures. This paper reports the results of an experimental program that was carried out to evaluate the effect of reinforcement corrosion on the flexural performance of RC beams and to investigate the efficiency of externally bonded carbon fiber reinforced polymer (CFRP) sheets to repair the corrosion-damaged RC beams. Seven RC beams with the same cross section and reinforcement details were prepared including the control beam (B0). First tension reinforcements of six RC beams were corroded by using an accelerated impress-current process to obtain corrosion levels of 15% 30% and 50% of weight loss according to Faraday’s law. Then three beams were repaired using CFRP sheets attached to the bottom surface leaving the other three unrepaired. All beams were subjected to the four-point bending load test. The experimental results show that the corrosion specimens demonstrated a significant deterioration on the structural performance and the integrity by decreasing in their ultimate load capacity stiffness and ductility. The deterioration by corrosion of tension reinforcements can be successfully overcome using CFRP sheets as the repair material. The technique can restore the beam strength to its original design strength except specimen B50F2 having severe steel-corrosion damage of 50%. A conservative value of the ultimate bending capacity of the beams with low corrosions (15%-30%) can be predicted by using RC conventional models as suggested in ACI 318. However the opposite trend is obtained for the high corrosion beam (50%). Appling ACI 440.2R provision to predict the ultimate flexural capacity of corroded beams repaired with CFRP sheets shows rather fair values for low corrosions (15%-30%) but significantly overestimates the strength of the high corrosion beam (50%).

2565
การสังเคราะห์สารหน่วงไฟกลุ่มฟอสฟอรัสที่ปราศจากธาตุฮาโลเจนสาหรับใช้งานบนผ้าฝ้าย
การสังเคราะห์สารหน่วงไฟกลุ่มฟอสฟอรัสที่ปราศจากธาตุฮาโลเจนสาหรับใช้งานบนผ้าฝ้าย

The aim of this study was to synthesize a non-halogen phosphate based flame retardant by using chitosan and phosphate compound as substances. The P-N synergistic effect was required in this study. After synthesizing the flame retardant was coated on cotton fabric by dipping then the fabric was tested for flame retardant properties compared to untreated cotton fabric. The three products with N and P in structure were gained by synthesis and confirmed by H-NMR spectroscopy. The time of combustion raised from 14 seconds in untreated cotton to 21 seconds in cotton that treated by product No. 2. Next the mechanical properties of treated cotton fabric are going to measure and the variation of techniques to apply flame retardant on fabric surface is going to test.

2560