砾质土体转化为粘性泥石流的机理研究
文献类型：学位论文
| 作者 | 王鹰 |
| 学位类别 | 硕士 |
| 答辩日期 | 1991 |
| 授予单位 | 中国科学院成都山地灾害与环境研究所 |
| 授予地点 | 成都 |
| 导师 | 周必凡 |
| 关键词 | 砾质土体 准泥石流 粘性泥石流 转化过程 转化条件 |
| 学位专业 | 自然地理学 |
| 中文摘要 | 砾质土体是砾石含量介于10-50%之间，由泥、砂、石、水组成的土体。国内外现有的研究成果表明，这种土体在泥石流形成时，常转化成粘性泥石流。本文基于理论分析和实验研究，结合野外考查，通过砾质土体与粘性泥石流体基本性质的对比研究，砾质土体向粘性泥石流转化过程和转化条件的分析，得出以下结论：1、砾质土体向粘性泥石流转化分为三个过程，即砾质土体充水过程，准泥石流形成的过程，粘性泥石流形成过程。2、充水过程分为缓慢充水，瞬间充水。前者与土体的水量递增有关，后者与暴雨产生的坡面径流有关，最基本类型的转化条件为：缓慢充水过程：W ≥ W_L瞬间充水过程：tanθ ≥ (β(τ_s-τ_W)tanΦ)/(R_(TW)C~2)3、准泥石流过程分为土力类和水力类。4、粘性泥石流过程是砾质土体与水混合、搅拌、流动和停淤的过程5、砾质土体机械组成的颗粒级配怪砾质土体向粘泥石流转化有较大影响，有利于转化的级配范围为：》2mm, 55-70% 2-0.05mm, 15-25% 0.05-0.005mm, 5-15% <0.005mm, 5-10% 6、砾质土体堆积的土坡形态影响砾质土体向粘性泥石流的转化；缓坡坡度在20-25°，陡坡坡度在30-40°，形成区沟床坡度在12-15°时，对其转化有利。7、一次降雨过程的不同阶段对砾质土体向粘性泥石流转化有不同的影响。前期雨量影响砾质土体的流水过程，激发雨量影响充水过程向准泥石流过程的转化，持续雨量影响准泥石流向粘性泥石流的转化。8、粘性泥石流的形成是砾质土坡地貌演变的一个特殊阶段。9、粘性泥石流体既不同于土体，也不同于高含沙水体，固体物质和水在粘性泥石流体中都失去了自身固有的一些特性，而形成了一种新的混合体。 |
| 英文摘要 | Gravelly soil, composed of clay, sand, gravel and water, gravel contents in it from 10 percent to 50 percent, offen changes into viscous debris flow. Basing on theory analysis, experiment study and combining with investigation, achieved points read as follows. 1. Gravelly soil changing into viscous debris flow may be divided into three stages, filling water, quasi-debris flow and viscous flow stages. 2. The filling water stage includes slow filling water and quick filling water. The slow filling water is due to increasing progressively of moisture content of gravelly soil. The quick filling water are related to surface flow caused by heavy rain. They may be determined by relations. Slow filling water: W ≥ W_L Quick filling water: tanθ ≥ (β(τ_s-τ_W)tanΦ)/(R_(TW)C~2) 3. The quasi-debris flow stage may be divided into soil mechanics and hydrodynamics debris flows. Their conditions may be determined by relations. 4. The viscous debris flow stage is a process of mixing, stirring, flowing, stooping and silting of mixture of gravelly soil and water. 5. Grain-size distribution in gravelly soil affect gravelly soil changing into viscous debris flow. The distribution ranges with advantage are: >2mm, 55-70% 2-0.05mm, 15-25% 0.05-0.005mm, 5-15% <0.005mm, 5-10% 6. Deposit shapes of gravelly soil influence converting of gravely soil to viscous debris flow. The favobrable angle ranges of slope to convert are: Slow slope, 20-25° Steep slope, 30-40° Gully bed of forming area, 12-15° 7. The different phases of a raining process have a different effect on gravelly soil changing into viscous debris flow. Beginning rainfall affects filling water process of gravelly soil. Arousing rainfall lead filling water process to quasi-debris flow. Lasting rainfall cause quasi-debris flow changing into viscows debris flow. 8. A formation of viscous debris flow is a special phase of landform evolution of slope. 9. A viscous debris flow is either different from soil or different from hyperconcentred flow. In viscous debris flows, soil and water all lose their own characteristics and form new natures of a mixture. |
| 语种 | 中文 |
| 公开日期 | 2015-02-02 |
| 源URL | [http://ir.imde.ac.cn/handle/131551/7766]  |
| 专题 | 成都山地灾害与环境研究所_成都山地所知识仓储（2009年以前） |
| 推荐引用方式 GB/T 7714 | 王鹰. 砾质土体转化为粘性泥石流的机理研究[D]. 成都. 中国科学院成都山地灾害与环境研究所. 1991. |
入库方式： OAI收割
来源：成都山地灾害与环境研究所
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