Suspended sediment load transport in the Mississippi River basin at St. Louis: temporal scaling and nonlinear determinism

This study investigates the dynamic behavior of suspended sediment load transport at different temporal scales in the Mississippi River basin. Data corresponding to five successively doubled temporal scales (i.e. daily, two‐day, four‐day, eight‐day and 16‐day) from the St. Louis gaging station in Missouri are analyzed. The investigation is focused on identifying possible low‐dimensional deterministic behavior in the suspended sediment load transport dynamics, with an aim towards reduction in model complexity. The correlation dimension method is used to identify low‐dimensional determinism. The suspended sediment load dynamics are represented through phase‐space reconstruction, and the variability is estimated using the (proximity of) reconstructed vectors in the phase space. The results indicate the presence of low‐dimensional determinism in the suspended sediment load series at each of the five temporal scales, with the variables dominantly governing the dynamics in the order of three or four. These results not only suggest the appropriateness of relatively simpler models but also hint at possible scale invariance in the suspended sediment load transport dynamics. Copyright © 2006 John Wiley & Sons, Ltd.     

雅安市魏家岗加油站工程滑坡形成条件及治理措施

魏家岗滑坡因保坎条石砌筑的施工质量差，保坎上又堆放弃土增加荷载，加之雨水渗透而形成工程滑坡，本文对滑坡形成的条件进行了论述，并提出了治理滑坡的措施。     

水平荷载作用下单桩非线性m法试验研究

通过对大量模型试验结果的分析，提出了简便合理的水平荷载作用下单桩的计算方法。该方法将常用m法中单一m值与位移建立指数关系，并由bm有k两参数来描述。将这一关系引和常用单桩m法计算中，则计算结果可考虑单桩非线性响应影响。     

LONG TERM EFFECTS OF REHABILITATION MEASURES ON BED LOAD TRANSPORT AT THE SALZACH RIVER

1 BASIC PROBLEMFlood protecton, sPreaing of settlements and occuPatin Of river valleys were maor reasons to damand lindt rivers throughout Europe in the ndd 19th century. Engineers of those days often knew very wellabout the effects of their plannings: shortening the river length would accelerat the now and thusencourage the erosion into the river's sedAnents. Two vital advanages could be obtalned from that kindof constrUction, landuse of the fOrmer flood plains on the one and increasin…     

RESUSPENSION OF FINE SEDIMENT IN RESERVOIRS - A CASE STUDY OF THE LOWER INN RIVER

1 THE LOWhR unR INNThe Inn river has its source in the alPine region of the GraubUnden canton of Switzerand. ThecatChment area of about 260(X} kIn2 includes mountains of the central Alpes up to 40(X) m. The river runs5l7 km thrOugh the countries of SwitZerand, Austria and Germany on itS way into the Danube mver. Thedischarge of the river at its mouth in the city of Passau is mainly infiuenced by the snow melt in themountainous catchment area and vches between apProx. 200 m3ls durin…     

A research on grey numerical imitation and modeling of groundwater seepage system

Based on grey set, grey numbers and their operation properties, the grey numerical model of groundwater seepage system was set up for the first time, the whole grey solving method of the model was given and it was proved that the common solving method of the model was only a special case of the grey solving methods. At the same time, the grey solving method was compared widely with common solving method, classical numerical method. The study shows that the grey solving method is better in depicting the procedure of transporting grey data of groundwater system. On the basis of the theoretical study, two basic kinds of cases about groundwater seepage were selected: the prediction of pit yield and the evaluation of groundwater resources on a groundwater basin. In the cases, systematical analyses were made for generalization and greylization of the hydrogeologic conditions, setting up of the grey model, identification and correction of the model as well as its prediction and evaluation. It was pointed out that when the grey numerical model is used to predict pit yield, the upper limit of the “grey band” of groundwater level cannot be higher than planed safe groundwater level, when evaluating the groundwater resource, the lower limit of the “grey band” of groundwater level cannot be lower than controlled level of groundwater.     

细颗粒对粗颗粒床沙质输沙率影响的初步研究

考虑高含沙紊流涡团中细颗粒絮凝形成网络结构对粗颗粒运动影响后,建立了粗颗粒悬移质泥沙的输沙率计算方法.该方法中包含的细颗粒影响项反映了流域因素对粗颗粒泥沙输沙的影响,证明细颗粒的影响是引起多沙河流中“多来多排”现象的一个重要因素.与黄河实测资料的对比表明,该计算方法能够反映高含沙紊流输沙时随流域细颗粒增多粗颗粒悬移质输沙率相对增大的现象,并具有较好的计算精度     

桩的荷载传递函数法及其在西安地区旋挖钻孔灌注桩中的应用

首先对桩的荷载传递法进行了分析，通过对工程实测资料的研究，发现西安饱和黄土地基中旋挖钻孔灌注桩桩侧摩阻力传递函数符合双曲线规律，并探讨了双曲线模型参数的理论计算方法。最后结合一工程实例证明利用荷载传递函数法，根据土质参数来计算单桩Q?s曲线是可行的。     

对粉喷桩检验方法的认识和探讨

介绍了检验复合地基承裁力及桩身完整性的主要方法静裁荷试验、低应变反射波法，并对检测应满足的前提条件进行了认识和探讨。     

Elastic waves in visco-elastic half-space generated by various vehicle loads

In this paper, the response of a visco-elastic half-space subjected to moving loads with static and dynamic components is investigated. Four types of vehicle loads are considered, including the moving point load, uniformly distributed wheel load, elastically distributed wheel load, and a train load simulated as a sequence of elastically distributed wheel loads. In each case, the influence of the moving loads traveling in the subsonic, transonic and supersonic ranges on the dynamic responses of the half-space is studied. The parametric study conducted herein enables us to grasp insight into the mechanism of wave propagation for a visco-elastic half-space under moving loads.