Different Water Temperature Mixing Gypsum Plaster Model Of The Compressive Strength, Bending Strength And Dimensional Accuracy Of The Impact

Objective: This study focused on two types of gypsum model (an ordinary plaster of super anhydrite) stirs and pours into the model after the different water temperature, Distinction laying aside different time section, Survey plaster model resistant to compression, bending strength and size change, look for mixed plaster model in order to find the best temperatureMethods: Prepare the an ordinary plaster and super anhydrite solution with a certain ratio and make a cylinder with a resistance to compression of 20mm, and a anti-bending strength of 40mm. Each kind should be divided into 28 groups. Put them in the temperature of 0℃, 5℃, 10℃, 15℃, 20℃, 25℃, 30℃respectively and agitate the plaster. Leave them there for 0.5 hours, 1 hours, 6 hours, 24 hours. Then, measure the changes of resistance to compression and anti-bending strength and size changes.Results:⑴There are significant difference between the compressive resistance of each group of ordinary gypsum (p<0.05), the significant difference was found in each ultra-anhydrite group after comparison (p<0.05)⑵When each group of ordinary gypsum was compared, significant differences were found in bending resistance (p<0.05). the bending resistance were significantly different in each group of super anhydrite (p<0.05)⑶After two kind of gypsum's carries on the statistical analysis after different water temperature agitation size changes, pairs the"T"not remarkable difference, (p>0.05).Conclusions:⑴Different water temperature in mixing ordinary gypsum and anhydrite super plaster model for the size change has no effect. Its size stability is good.⑵Different water temperature mixing ordinary gypsum plaster model of the compressive, flexural strength has a significant impact. And various temperatures (0℃, 5℃, 10℃, 15℃, 20℃, 25℃, 30℃) it's resistant to compression. The bending strength strengthens (0.5 hour, 1 hour, 6 hour, 24 hours) gradually along with the time growth. 15℃degrees of compressive flexural strength is the best.⑶Different water temperature mixing ordinary super anhydrite plaster model of the compressive, flexural strength has a significant impact. And various temperatures (0℃, 5℃, 10℃, 15℃, 20℃, 25℃, 30℃) its resistant to compression. The bending strength strengthens (0.5 hour, 1 hour, 6 hour, 24 hours) gradually along with the time growth. 15℃degrees of compressive flexural strength is the best.