蒸压加气混凝土及其复合墙体抗冻性能试验研究

发布时间：2018-10-23 18:22

【摘要】：随着我国对能源需求的不断增长，能源问题已经成为我国所面临的重大考验之一。为了保护有限的能源资源，我国的能源建设已逐渐从开发向节约的发展方向转移。建筑节能作为能源节约的重点领域，已成为各国研究者们的研究重点。为响应国家能源节约建设的号召，长沙理工大学提出了一种钢筋混凝土剪力墙复合加气混凝土砌块自保温体系，本文主要负责该体系的抗冻性研究。对加气混凝土复合墙体的抗冻性研究必须以加气混凝土的抗冻性研究为基础。目前，国内外对蒸压加气混凝土抗冻性能的研究还较少。因此，本文对完善加气混凝土抗冻性研究和推广加气混凝土复合墙体保温体系具有重要意义。研究和分析表明，孔结构是影响材料抗冻性能的主要因素，而材料的吸水特性可以粗略的反应其孔结构。本文在研究加气混凝土材料吸水特性与孔结构的关系时引用了吸水动力学的基本原理，并通过3组15块试件的吸水试验后得到的吸水曲线图总结了孔结构与吸水特性的关系。在研究孔结构与抗冻性能的关系时通过对参考文献的总结和分析，，将加气混凝土内的孔隙按照孔径和对抗冻性能的影响的不同划分为有害孔与无害孔，并与材料的吸水特性相结合，通过4组60块加气混凝土试件的冻融循环试验提出了以加气混凝土的吸水特性来表征其抗冻性能的方法，同时，基于这一方法提出了加气混凝土抗冻性指标，并根据不同地区抗冻等级的要求，得到不同地区的抗冻性指标和强度的限值。对复合墙体粘结面抗冻性能的研究采用了双剪试验法和劈拉试验法。通过40块双剪及劈拉试件的冻融循环试验结果表明，双剪试验无法较好的反应粘结性能；而在劈拉试验中发现，冻融作用会使粘结面的抗拉强度大幅下降。
[Abstract]:With the increasing demand for energy in China, energy problem has become one of the major challenges facing our country. In order to protect the limited energy resources, the energy construction in our country has gradually transferred from development to saving. As a key area of energy conservation, building energy conservation has become the research focus of researchers all over the world. In order to respond to the call of national energy conservation construction, a reinforced concrete shear wall composite aerated concrete block self-insulation system is proposed in Changsha University of Technology. This paper is mainly responsible for the study of the frost resistance of the system. The study of frost resistance of aerated concrete composite wall must be based on the study of frost resistance of aerated concrete. At present, there are few researches on frost resistance of autoclaved aerated concrete at home and abroad. Therefore, this paper is of great significance to improve the frost resistance of aerated concrete and popularize the insulation system of aerated concrete composite wall. The research and analysis show that the pore structure is the main factor affecting the material's antifreeze property, and the water absorption property of the material can roughly reflect its pore structure. In this paper, the basic principle of water absorption dynamics is used in the study of the relationship between the water absorption characteristics and pore structure of aerated concrete materials, and the relationship between the pore structure and the water absorption characteristics is summarized through the water absorption curves obtained from the water absorption tests of 3 groups of 15 specimens. By summarizing and analyzing the relationship between pore structure and frost resistance, the pores in aerated concrete are divided into harmful pore and harmless pore according to the pore size and the influence on freezing resistance. Combined with the water absorption characteristics of the material, through the freeze-thaw cycle test of 60 pieces of aerated concrete, a method to characterize the frost resistance of the aerated concrete by its water absorption property is put forward, at the same time, the freezing resistance of the aerated concrete is characterized by the freezing and thawing cycle test of the aerated concrete. Based on this method, the frost resistance index of aerated concrete is put forward, and according to the requirements of frost resistance grade in different regions, the freezing resistance index and the limit value of strength are obtained in different areas. Double shear test method and split tensile test method are used to study the frost resistance of the bonding surface of composite wall. The results of freezing and thawing cycles of 40 double shear and split tensile specimens show that the double shear test is not able to improve the reaction bond performance, but in the split tensile test, the freezing and thawing effect can greatly decrease the tensile strength of the bonding surface.
【学位授予单位】：长沙理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU528

【参考文献】