再生塑料泡沫混凝土的制备与基本性能研究

发布时间：2019-04-22 08:27

【摘要】：随着中国长久以来粗放式发展的急剧扩张,环境问题日益突出,污染呈现出愈演愈烈之势。昔日的蓝天白云、青山绿水因为污染的加重而逐渐的消失。每年冬季以后频频爆发的全国范围内的雾霾也在向人们揭示着中国环境污染的严重性和生态的脆弱性。实行可持续发展,减少对生态环境的破坏已经成为了未来中国生存和发展必然要走的道路。泡沫混凝土作为一种新型保温材料,生产能耗低,保温性能优异,而且可以利用工业废弃物,能够降低建筑物夏天降温和冬天供暖的能耗,符合未来低碳低能耗、绿色建材的前进方向。塑料是生产生活中必不可少的材料之一,而废旧塑料不能自然降解,依靠焚烧或掩埋解决又会给环境带来了负荷。国内外研究人员将这些废弃塑料回收后,清洁破碎成颗粒变为再生塑料,并掺入到混凝土中进行性能研究,为废弃塑料的重新利用开辟一条新的途径。本文将再生塑料作为轻集料掺入到泡沫混凝土中,围绕其制备和基本性能开展研究。主要研究成果如下:(1)通过单因素试验分别研究物理发泡工艺中搅拌速率、搅拌时间以及外加剂掺量(减水剂、稳泡剂)对再生塑料泡沫混凝土性能的影响,从而确定配合比,并通过发泡剂试验和塑料掺量试验确定了后续正交试验多因素的水平范围。试验结果表明:发泡剂稀释液的搅拌速率宜为500r/min,搅拌时间没有固定最佳值,且与加入的发泡剂用量有关。减水剂和稳泡剂的最佳掺量分别为1.25%和0.04%。(2)通过正交试验法研究塑料种类、塑料掺量和发泡剂掺量三个因素对再生塑料泡沫混凝土干密度、吸水率、抗压强度和导热系数的影响。试验结果表明:发泡剂掺量对试块性能的影响比塑料种类和塑料掺量更为显著,干密度、抗压强度和导热系数随着发泡剂掺量的增加而下降,吸水率则持续上升。在塑料掺量不断增大的情况下,试块干密度和抗压强度曲线先上升后下降,吸水率和导热系数则呈先下降后上升的相反趋势。当塑料掺量为15%,试块的综合性能最优。五种塑料中,掺入ABS的试块的干密度上升幅度较大,其余各性能均得到加强,HDPE、MDPE、未改性PP、改性PP的掺入将使试块的不同性能得到改变。综合比较后,ABS的表现最为优异。(3)通过曲线拟合,分别得出再生塑料泡沫混凝土的干体积密度与抗压强度、干体积密度与孔隙率、导热系数与干体积密度的关系,并根据保温试验数据,推导并验证出其三相导热系数模型。
[Abstract]:With the rapid expansion of extensive development in China for a long time, environmental problems are becoming more and more prominent, and pollution is becoming more and more intense. The former blue sky and white clouds, green mountains and green water due to increased pollution and gradually disappear. The country-wide haze, which erupts frequently after winter, also reveals the severity of environmental pollution and ecological fragility in China. To carry out sustainable development and reduce the damage to ecological environment has become the inevitable path for the survival and development of China in the future. As a new type of insulation material, foam concrete has low production energy consumption, excellent thermal insulation performance, and can utilize industrial waste, which can reduce the energy consumption of building cooling in summer and heating in winter, which is in line with the low carbon and low energy consumption in the future. The direction of green building materials. Plastic is one of the essential materials in production and life, and waste plastics can not be degraded naturally, and the environment will be loaded by burning or burying. After the waste plastics were recycled by researchers at home and abroad, the particles were cleaned and broken into recycled plastics, and the properties of the waste plastics were studied by mixing them into concrete, which opened up a new way for the reuse of waste plastics. In this paper, recycled plastics are added into foam concrete as lightweight aggregate, and the preparation and basic properties of recycled plastics are studied. The main results are as follows: (1) the effects of mixing rate, mixing time and admixture amount (water reducer, stabilizer) on the properties of recycled plastic foam concrete were studied by single factor test. The mixing ratio was determined, and the horizontal range of multi-factor of subsequent orthogonal test was determined by foaming agent test and plastic content test. The experimental results show that the stirring rate of the foaming agent diluent is 500 rmin, the stirring time is not fixed, and it is related to the amount of foaming agent added. The optimum dosage of water reducing agent and foam stabilizer is 1.25% and 0.04%, respectively. (2) through orthogonal test, the effects of plastic type, plastic content and blowing agent content on dry density and water absorption of recycled foam concrete are studied. The influence of compressive strength and thermal conductivity. The experimental results show that the effect of blowing agent content on the properties of the test block is more obvious than that of plastics and plastics. The dry density, compressive strength and thermal conductivity decrease with the increase of foaming agent content, while the water absorption rate continues to increase. Under the condition of increasing plastic content, the curve of dry density and compressive strength first increased and then decreased, while the water absorption and thermal conductivity decreased first and then increased. When the content of plastic is 15%, the overall performance of the test block is the best. Among the five kinds of plastics, the dry density of the test block doped with ABS increased greatly, and the other properties were strengthened. The addition of PP modified by HDPE,MDPE, unmodified PP, would change the different properties of the test block. (3) through curve fitting, the relationship between dry volume density and compressive strength, dry volume density and porosity, thermal conductivity and dry volume density of recycled plastic foam concrete was obtained, and the relationship between dry volume density and porosity, thermal conductivity and dry volume density of recycled plastic foam concrete was obtained by curve fitting. According to the thermal insulation test data, the three-phase thermal conductivity model is deduced and verified.
【学位授予单位】：安徽工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU528.2

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