废弃混凝土再生骨料的技术研究
摘 要
随着建筑行业的快速发展及大量建筑的拆除，我国混凝土的工业面临两大难题：一方面是资源危机，商品混凝土使用大量的天然骨料；另一方面是环境危机，废弃混凝土和报废的结构混凝土产生的建筑垃圾既占用了宝贵的土地又造成了环境污染。我国目前对再生混凝土的研究和利用还很少。 本试验主要研究了以下问题：
1. 本试验通过再生混凝土粗骨料的制备，测试再生粗骨料的各项物理性质，对再生粗骨料的性质与一般天然粗骨料的性质进行对比，区分，得出再生混凝土粗骨料的特性。并采取一定措施，使得再生混凝土粗骨料的性质与天然骨料的性质相近。
2. 本试验还通过研究对配合比进行设计，并且考虑了再生混凝土骨料吸水率大这一特性，在满足坍落度的要求的情况下，设计了配合比。
3.通过废弃混凝土再生粗骨料制备及对再生粗骨料的性质分析，研究了不同再生粗骨料取代率下，混凝土的配合比问题，并通过试验测出不同掺量下混凝土强度的变化，得出了再生混凝土在不同再生骨料取代率下的强度性能及设计建议。
关键词：再生混凝土；再生骨料；吸水率；抗压强度；基本性能
I
安徽建筑工业学院本科生毕业论文
ABSTRACT
As buildings close down, the concrete industry faces two major challenges: one is a resource crisis, the pouring of concrete using a large number of natural aggregate; the second,the environmental crisis, abandoned the structure of concrete and scrap concrete in construction waste. It not only takes up valuable land that causes environmental pollution.Currently our country has little research available on this topic and not much use for recycled concrete.
The major research project by testing as follows:
1.This project test the physical properties of recycled aggregate through the preparation of recycled concrete aggregate. comparing and distinguishing The nature of the recycled aggregate and the general nature of natural aggregates,we can obtain the characteristics of recycled concrete aggregate. And take some measures to make the nature of recycled concrete aggregate be similar to the natural aggregate;
2.In this paper,we design the mix through the experimental research project , and considered a large water absorption of recycled concrete aggregate , in meeting the requirements of the slump, we design the mix proportion of each group;
3. By preparation of recycled concrete aggregate and the analysis of the nature of recycled aggregate,we study the concrete mix of different content of recycled aggregate.Through testing the veriaty of the strength under different content of recycled aggregate,we obtain the different strength properties and some design proposals.
Keywords: Recycled concrete; Recycled aggregate; Compressing strengh; Water absorption; Basic performance
II
废弃混凝土再生骨料的技术研究
目录
摘 要 ..................................................... I ABSTRACT .................................................. II 第1章 绪论 ................................................ 1
1.1引言 ............................................. 1 1.2再生混凝土技术国内外研究现状 ..................... 2 1.2.1国内再生混凝土技术研究现状 ................................................ 2 1.2.2国外再生混凝土技术研究现状 ................................................ 4 1.3 再生骨料的分类 ................................... 5 1.4本课题拟解决问题及设计思路 ....................... 5 1.4.1本课题拟解决问题 ................................................................. 5 1.4.2设计思路 ............................................................................... 6
第2章 实验 ............................................... 7
2.1研究思路 ......................................... 7 2.2试验原材料 ....................................... 7 2.2.1．水泥 ................................................................................... 7 2.2.2．骨料 ................................................................................... 8 2.2.3. 水 ........................................................................................ 9 2.3试验设备 ......................................... 9 2.4再生混凝土粗骨料 ................................ 10 2.4.1再生混凝土粗骨料的来源 ..................................................... 10 2.4.2再生粗骨料的分离工艺 ........................................................ 11
III
安徽建筑工业学院本科生毕业论文
2.5 再生粗骨料的主要性能指标 ........................ 12 2.5.1压碎指标 ............................................................................. 12 2.5.2吸水率................................................................................. 13 2.5.3堆积密度 ............................................................................. 14 2.5.4表观密度 ............................................................................. 14 2.6再生混凝土配合比设计 ............................ 15 2.6.1再生混凝土配合比设计 ........................................................ 15 2.6.2试配及调整 .......................................................................... 16 2.7再生混凝土强度试验及结果 ........................ 17 2.7.1再生混凝土试件的制备 ........................................................ 17 2.7.2强度测试结果 ...................................................................... 19
第3章 试验结果与理论分析 ................................. 20
3.1 试验结果 ........................................ 20 3.1.1再生粗骨料的吸水率分析 ..................................................... 20 3.1.2再生粗骨料取代率对再生混凝土和易性的影响 ...................... 21 3.1.3不同处理条件下再生粗骨料取代率对再生混凝土抗压强度的影
响 ...................................................................................................... 22
3.1.4不同处理条件下再生粗骨料取代率对再生混凝土抗压强度提升
率的影响 ............................................................................................ 23
3.2 理论分析 ........................................ 24 3.2.1再生粗骨料不同取代率对再生混凝土流动性及强度的影响 ..... 24 3.2.2未经处理的再生混凝土强度分析 ........................................... 24
IV
废弃混凝土再生骨料的技术研究
3.2.3预泡水处理的再生混凝土强度分析 ....................................... 25 3.2.4相同取代率的再生混凝在不同处理条件下的强度比较分析 ..... 25
第4章 结论与展望 ......................................... 26
4.1结论 ............................................ 26 4.2展望 ............................................ 27 参考文献 .................................................. 28 致谢 ...................................................... 30
V