【作者】 杨胜发；

【导师】 方铎；

【作者基本信息】 四川大学 ， 水力学及河流动力学， 2003， 博士

【摘要】 河水最终注入海洋的河流称为外流河，河水最终不能注入海洋的，或消失于沙漠，或注入湖泊的河流称为内流河。每一条河流各自具有自己的特性，钱宁把河流按不同的性质分成游荡、分汊、弯曲、顺直四类。一条河流的各个河段也具有各自的特性，我国公路部门根据河段稳定性的特点及变形特点，把全国各地河流概括地划分为7类河段：①深槽稳定河段；②浅槽稳定河段；③宽浅变迁河段；④宽浅游荡河段；⑤边滩微弯河段；⑥宽滩蜿蜒河段；⑦冲积漫流河段。本文主要研究对象是内流河宽浅变迁河段。 我国河流内流区占全国面积的36％，但径流总量只占全国的4.35％。新疆共有315条河流，除额尔齐斯河最终注入北冰洋外，其余全是内流河。由于我国内流河的径流量所占份额很小，加之历来视西部为荒芜不毛之地，对其多方面的研究、发展甚少关注，这也是同样表现于对内流河的研究长期被忽视，西部大开发战略一经提出，其深远意义和丰富的内涵便立即显示出来。西部大开发应抓住时机，着眼于少数民族地区经济资源可持续发展等战略性目标，对一些带有战略性的建设项目，作出统筹安排。在西部地区的农业、交通、能源等重大开发任务的实施中，无不涉及对这一地区为数不多、十分珍贵的内流河的开发和利用。为此，交通部2001.9立项“新疆宽浅、变迁性河流桥涵设计关键技术研究”(2001-318-365-88)，本文结合该项目对内流河的水沙特性作较为系统的研究。 内流河宽浅变迁河段不同于以往我们所了解的河流，其独特的水沙特性向我们提出了一系列有待研究的新课题。同时，由于以前我们对此类河段研究很少，可查阅和借鉴的资料不多，很多方面还只停留在现象的认识上，对于其水流泥沙运动的本质规律认识还相当不够。为此作者在收集前人研究成果的同时，到南疆和北疆对25条有代表性的宽浅变迁河段进行调研，选取呼图壁河和三屯河作为样本河段进行详细测量，并根据宽浅变迁河段的特性设计了一套四川大学博士学位论文变坡水槽泥沙起动以及输沙试验系统，对内流河的分布、洪水成因、山前平原形成、小尺度粗糙临界值、大比降河床的定床阻力和动床阻力、大比降粗颗粒泥沙起动、内流河宽浅变迁河段的泥沙输移特性以及动床模型设计等多方面进行了理论分析和研究，取得了如下一些研究成果。 (1)我国内外流区的分界线，北起大兴安岭，沿东北、西南方向，经阴山、贺兰山、祁连山、日月山、巴颜喀拉山、念青唐古拉山和冈底斯山，直到西藏西部的国境为止。内流河主要分布在新疆、河西走廊、柴达木盆地、内蒙古和西藏北部。东北淞嫩地带也有局部内流区。新疆内流河宽浅变迁河段主要位于山麓平原的冲击扇或洪积扇上，冲击扇和洪积扇的厚度少则几十米，多达上百米。 (2)内流河多数属于季节性河流，影响宽浅变迁河段水沙特性主要是洪水来量。从成因方面概括而言，其洪水可分为五种:暴雨洪水、季节融雪洪水、高山融雪洪水、棍合洪水和水利枢纽泄洪及溃堤引起的洪水。 (3)内流河宽浅变迁河段从平面形态上分为两类:一类是限制性变迁河段，另一类是非限制性变迁河段。内流河宽浅变迁河段的河床比降较大，一般在10%0以上;在特大洪水时，多为300一500衬/s;在一般洪水时，水流多以股流形式存在，且单宽流量一般为2一3ms/s.m，特大洪水时，超过4 ms/s.m:在洪水期，悬移质含沙量是月平均含沙量的几倍、几十倍甚至上百倍;河床组成的颗粒较粗(D50=16~50rn们以);级配较宽，由细沙、砾石、卵石直至于漂石组成，非均匀系数一般为5~9，个别河段超过30。 (4)采用乒乓球模拟颗粒排列紧密的大比降河床，通过流速分布试验确定内流河宽浅变迁河段的小尺度粗糙的临界值。产刃犬:>3为小尺度粗糙，2<却犬:<3时，仍然服从对数分布规律，只是精度稍差。小尺度粗糙的临界值~浓*、。廿二。**八去、，体平、UI、__y+0·36K:.八，击工业川耳州闪匕刀J。步专名些鱿瓦刃几又犯刀，叩口，刁义J之工、刀:::一=丁in一一一二万一一一一十，·，f。田J川 U .k式:y0二0.36K，>0，可忽略粘性底层，糙率尺寸对水流阻力起主要作用。 (5)通过流速分布试验确定的定床阻力与通过大比降粗颗粒的泥沙起动所确定的定床阻力相比较，尽管两次试验的方法不同，其结果吻合较好。说明大比降粗颗粒的定床阻力系数与相对光滑度的1/6成正比，符合曼宁公式形式。’四川大学博士学位论文这一结果给谢才一曼宁公式可确定急流状态下的定床阻力提供很好的例证。 (6)综合室内水槽试验和呼图壁河现场资料进行分析，大比降粗颗粒河床的动床阻力为:碑了一6.01(H/D)，‘6习‘’。从拟合结果来看，相关系数达到O·”“7，该公式有较好的可靠性。说明内流河宽浅变迁河段的动床阻力不但与相对光滑度有关，还与水流状态(弗汝德数成)有关。对于卵砾石河床的动床阻力的问题，现有成果很少涉及，属于比较新的泥沙问题。作者关于这方面研究具有探索性，起抛砖引玉的作用。 (7)分析现有各种起动标准，通过泥沙起动判别试更多还原

【Abstract】 Rivers are classified into two types. One is called outer river which flows into ocean and the other is called inner river which can not flow into the ocean but into the desert or lakes. Each river has its own characteristics. Prof. Qian Ning categorizes rivers into four types according to their different features, i.e., migrating bed river, divaricating river, curved river, and straight river, each with it’s own distinct features. On the basis of the stability and shifting of rivers, the Ministry of Communications(MOC) generally divides rivers into seven types: (1)deep pool stable reach; (2)shallow pool stable reach; (3)broad-shallow shifting reach; (4)board-shallow migrating reach; (5)slightly curved reach; (6)meandering reach; (7)flood plain reach. This dissertation attempts to study the feature of the inner river’s broad-shallow shifting reach(IRBS reach).The whole area of all the inner river accounts for 36% of China’s.But its runoff occupies only 4.35%. There are 315 river in Sinkiang Region. All the river are inner river except the Eerqisi River which flows into the Arctic Ocean. The western region are often regarded as infertile, little attention had been paid on the studies and exploitation of the western region, to say nothing of the inner rivers. As soon as the Western Region Development project was brought forth the far-reaching influence of the inner rivers gradually became more important than ever before. The Western Region Development should grasp the great opportunity to enhance the sustainable development in this region. In order to development the agriculture, communications and energy resources, the exploitations of the few but precious inner rivers should be put on the agenda. Therefore MOC hasestablished the plan of the "study on the key technology of the bridge and culvert design in the IRBS reach of the Sinkiang Region" in September 2001(Contract No:2001-318-365-88). The paper presents results and findings of the study on the characteristics of flow and sediment transport in IRBS reach.The characteristics of the IRBS reach are different with river we have known before. The unique properties of the rivers has brought out many new problems needed to be resolved. Unfortunately few studies has been performed to deal with the concered problems and therefore the collection of the related data was very difficult. Based on the study of the previous scholars, the author had investigated 25 typical IRBS reach in the South Sinkiang and the North Sinkiang, and sampled the Hutubi river and Santun river to measuremnet. According to the survey data and the features of IRBS reach, a variable-slope flume experiment system was established for the sediment incipent motion and transportation in high slope bed. The problems were studied and analyzed as follows: (1)the distribution of the inner river, (2)the mechanism of flood forming, (3)the plain at the foot of mountains, (4) the critical value of small scale roughness, (5)static bed resistance and moveable bed resistance in the IRBS reach, (6)coarse sediment incipent motion in the high gradient bed, (7)sediment transportation features in the IRBS reach, and (8)the physical model design of the movable bed rivers. The major conclusions are as follows:(1)The divided line of the outer river and the inner river starts north from Daxinganling to the east-north, west-south direction, passes through the Yin Mountain, the Helan Mountain, the Qilian Mountain, the Riyue Mountain, the Bayankala Mountain, the Lianqingtanggula Mountain and the Gangdisi Mountain, and finally reches China’s west, Tibet border. Most inner rivers are located in Sinkiang,, Hexi aisle, Caidamu basin, Inner Mongolia and the north Tibet. Some local inner rivers locate in the Song Nen area. The IRBS reach mostly lie on the erosion and sedimentation fan plain at the foot of mountain. The depth of the fan usually is measured tens of or even hundredsof meters.(2) The inner rivers are mostly seasonal ones. The factors which influence the characteristics of the IRBS reach更多还原