The method of utilizing rain water has been well developed in foreign countries to realize the sustainable development of water recourse while the method is still at the initial level in China. When considering the increasing of water shortage and urban flood, the awareness of utilizing rain water, as an inevitable trend, has been applied to various engineering technologies. This article has analyzed the principle of conventional road drainage system and the application of artificial wetland technology, also proposed to combine the road drainage system and artificial wetland, as a complex drainage system, to utilize the urban rain water, decrease urban flood pressure, and improve urban micro environment. The calculation principle and method for the complex drainage system are included as well.

针对潜坝堵河也能成灾的现象,基于异重流理论导出了泥石流龙头运动方程;对泥石流龙头运动的影响因素进行了单因素分析.分析表明泥石流粘滞系数和切应力对龙头运动速度的影响不明显,绕流阻力系数对龙头运动速度的影响最大;给出了泥石流龙头在主河里的运移距离随时间的变化曲线,在此基础上给出了潜坝堵河的最小固体物质总量计算式.

River-blocking due to debris flow is one of the disaster-phenomena happened frequently in the mountain rivers. First, three forms of the debris-flow blocked river, which are the congestion by de?bris-flow submerged, the partial blockage and complete blockage, have been observed through tests in the lab. Meanwhile,it is proved that the total amount of debris-flow is an important factor in the river-block?ing events. Based on the process of river-blocking obtained by the laboratory tests, dynamic equations for fluid in the confluence area are established. Combining with the Particle-In-Cell (PIC) and Marker and Cell (MAC) method,a coupling model is presented for interaction between debris flow and the main river. The main characteristic of the model is that the rheological parameters and sediment settling velocity in the calculation unit of confluence may be expressed with the aid of the specific weight of mixed fluid. The ma?jor factors of debris-flow blocking the main river, such as velocity ratio of debris flow and flow in the main river, rheological parameters of debris flow, the total amount of debris flow etc., are analyzed through numerical simulation. On the basis of inductive analysis of experiment results and simulation re?sults, the reasons for using the momentum ratio as the critical condition determining the event of riv?er-blocking is explained,and a discriminate index for the river blockage is proposed,which is the product of momentum ratio and volume ratio of debris flow in the river.

According to the relationship between the water-supply buried pipeline and the foundation soil,the simple soil-pipe dynamic experimental devices were designed.The soil resistance to pipe and the soil-pipe relative displacement were determinated under the different axial vibration accelerations.The experiment results showed that the maximum soil resistance to pipe,the soil-pipe sliding critical displacement and the soil spring constant etc.depend on the vibration acceleration,depth of pipe and pipe materials.The experiments also showed that the maximum soil resistance to pipe on unit contacting area of cast-iron pipe is between 5N/cm to 25N/cm,and which of PE-pipe is between 2.1N/cm~2 to 6.9N/cm~2;the soil elastic limit displacement is very small and only about 0.1mm to 0.4mm;the equivalent soil spring constant of cast-iron pipe is between AN/mm/mm to SN/mm/mm,and which of PE-pipe is between 0.3N/mm/mm to 1.0N/mm/mm.

Ductile cast iron pipe is a tubular product,which is frequently used in city water-supply project.The seismic capability of joints is one of the factors,which must be considered in the design of water-supply network in seismic areas.To study the mechanical parameters of rubber gasket joints,a series of prototype drawing experiment are performed to investigate the regularity of joints drawing force and the joints displacement.The experimental results show that,rubber gasket joints for ductile cast iron pipe is favorable for earthquake-resistance;the allowed maximum joints displacement is about 3~4cm;the joints spring coefficient is between 32N/cm·cm-2 to 125 N/cm·cm-2and the maximum resistance is about 45~75N/cm2.

According to the characters of the submerged disk and the density current, the runout equations of the debris flow in the water is obtained, and the equation of the head-water level is given by the broad-crested weir theory. Based on the dynamic equation of the debris flow at different slopes, water and sediment dynamic processes, and the interaction between barriers dam of debris flow and main river were considered, and a model of the runout distance of debris flow in big river was established. In view of the phenomenon that the material erosion is very serious when debris flowing into big river, the erosion coefficient is obtaineding using the test dates of flume experiment. Based on the total amount equation of debris flow was blocking given by Bifan ZHOU, a modal of the total amount of the big river blocked by debris flow was considered in hight of the erosion coefficient. The criterion of debris flow blocking big river was presented in terms of dynamic process and total amount of debris flow.

通过对德阳市生活垃圾产量的分析与预测,结合德阳市的垃圾处理现状,从技术及经济效益两方面进行分析,提出适合于德阳市的垃圾处理优选方案。

我国现有桥渡水文设计规范有关斜交桥的冲刷计算没有考虑桥下水流流向偏转角度的影响,从而影响计算精度。文中通过FLUENT软件对不同斜交角度、不同压缩比条件下桥渡二维流场进行数值模拟,得到流向偏转角度随斜交角度和压缩比的变化规律,为斜交桥的冲刷计算开辟了新的途径。

New ideas of reforming for fluid mechanics experimental teaching in engineering course were expounded.The development for individualization experimental installation,and the practical process for opening the individualization experiment were mainly introduced.The practice shows that it is possible to establish the upgraded experiment for excellent students by reforming experimental installation,although the fund of experiment is not enough,and it is efficient to develop cultivation of innovative talents.

分析了当前城镇河道排洪设计的水力计算在自然因素和人为因素下的不确定性。根据可靠度理论,给出了基于可靠性设计的功能函数及计算步骤。由示例计算说明该方法的可行性和合理性,适合小流域城镇河道的可靠性水力设计。

The soil body going to wrack and ruin does not occur occasionally.It is controlled by some factors,which were variable and have not accurate value,such as the size and shape,surface characteristics,arrangement types and linking characteristics of the soil body.Through 3 different physical model tests,the author analyzed the damage course and fracture morphology of the tests and attained the influencing factors of fine sand accumulation and its inner damage mechanism.

At present, the design peak flow in urban channels is generally calculated with the rational formula from water conservancy authority and the formula for stormwater flow calculation from municipal authority, but the runoff and afflux characteristics and design standards in the urban area do not fit the conditions assumed for either of the formulae. Based on the said characteristics in modern urban areas, a rational formulae is hereby proposed, in which, the peak flow in the urban flood-relief channel is composed of the channel flow and slope runoff under some assumed condition. The said two formulae are adjusted to the practical situation, and their rationality is verified through calculation of a flood-relief channel in theurban area of Pengzhou.

Based on a large number of computer simulation experiments,physical model experiments and some theoretic a- nalysis,the three-dimensional discrete element method is modified.Firstly,the stability of the computer simulation is ana- lyzed by virtue of temporal curves of velocity.Secondly,the relationship between parameters and velocity distribution is dis- cussed via the temporal curves of variances.Finally,the correctness of models and the rationality of parameter adoption are further validated by the contour of macadam.

Reynolds experiment is an important experiment which shows the laminar flow and turbulent flow.This paper introduced a new design of Reynolds experimental installation based on the tradition Reynolds experimental installations.The new Reynolds experimental installation has some virtues of circle water system,water head stabilization and color dissolving automatically.It exhibits more advantage than tradition installations in the experimental teaching,and overcomes the limitations of tradition installations,therefore,this new installation can be used widely in experimental teaching of fluid mechanics.

The ash dam of one thermal power plant is constructed and filled by soil,gravels and crushed stones.When the side slope destructs, the plane of fracture approximates plane and straight in line in cross section. This theory is adopted to conduct analysis on the dam slope stability under conditions of seep and no seep.

To study the mechanism of confluence between debris flow and the main river,based on the theory of Newtonian and non-Newtonian fluid dynamics,the theoretical equation to describe the movement of debris flow in the confluence was established,and three-dimensional simulate model was also put forward,which includes numerical calculation method,the rheologic equation and the sediment deposit and transportation in a conjunction area.The calculation shows that this method is really feasible for analysis of the distribution of sediment density and the change of water level,the calculation results are in good agreement with the model test data.

Abstrcat A hierarchy structure model is established in the assessment of floodwater's discharge safety. When the model is analyzed by Analytic Hierarchy Process (AHP),the influencing coefficients (weighted coefficient)of factors influencing the floodwater's discharge safety are obtained. Then,the fuzzy comprehensive judgement theory is applied to give a comprehensive judgement of the floodwater's discharge safety system and a scientific and reasonable assessment.

通过大量的计算机模拟试验、物理模型试验及一定的理论分析,改进了三维离散单元法计算模型,并探讨了把该方法应用于城市管道工程建设中沟槽开挖边坡稳定性分析的可行性。

将传统实验"管路沿程水头损失"改造为综合性、设计性、实践性的实验.通过硬、软件的开发,使学生得到全面的训练,提高了实验教学质量.

Model similarity-rules for confluence between a debris flow and the main river were analyzed, and a series of model experiments were performed to investigate the regularity of confluence between a debris flow and the main river. The experimental result shows that the movement patterns of a debris flow are different in the intersection region for different relationships between the branch and the main river and can be divided the submerging flow and the stratification flow. In the submerging flow, the velocity of the debris flow head, submerging into water, decreases approximately linearly, the changes in its height and length are very small, and there is a linear relationship between the width and the length. All these are quite different from a density current. Furthermore, when water flows into the branch, the debris flow head will be broken by water, resulting in the sedimentation of sand and stone. Under that condition, the debris flow entering into the river becomes a stratiform flow.