Research Of Freight Volume Prediction And Navigation Conditions For Second-line Shiplock On Xijin Hydro-junction

Prediction of the freight volume of Waterway transportation is the main basis for determining the scale of water transport infrastructures. A reasonable and accurate prediction result of freight volume has the most significant effect on determining the investment and benefit of future waterway transportation engineering projects, making developing strategy for future waterway transportation and giving full play to benefit of waterway transport facilities. Ship-lock freight volume is a key index to measure inland navigation development, and there are many influnencing factors. Taking Xijin Second-lane Ship-lock as the samples, combining the current situation and development trend of the econominc developmrnt and the freight volume of waterway transportation in the hinderland area of Xijin Hydro-junction, this paper forecasts the middle-term and long-term demans of Xijin pass-dam freight volume by set up a prediction model with four mathematic methods, namely, regression analysis method, cubic exponential smoothing method, abstract mode selection model and growth rate method, and gets a corresponding prediction result of handling capacity by the input of certain years. According to the forecasts, Xijin pass-dam freight volume would be16.9million tons,27.6million tons,37.2million tons in2020,2030,2040respectively. The reasonable construction scale of Xijin Second-lane Shiplock is â…  ship-lock with the maximum traffic capacity of3000t based on the above information.Navigation building import and export area, namely the lock upstream approach channel and the river (or canal) is connected to the entrance area of ship lock and the river, is the import and export of free navigation River play a role of bond area, is the lockage vessels (team) import and navigation channel of the throat. When the channel and mainstream reach into certain angle approach entrance area, often appear a kind of role in ship side adverse navigating the complex flow pattern "oblique flow". As a result of oblique flow" role, will force the import of ship torsion and strong shock bump drift, deviated from the track, the vessel is not safe. Therefore, in a navigation hub design, needs to carry on the simulation test, understanding of the impact of the flow conditions at the entrance area of the mechanism, analysis of oblique flow forming reasons, and puts forward the improving flow conditions at the entrance area of all sorts of measures, have real sense.In this paper, taking on the Xijin Second-lane Shiplock approach channel as an example, through the establishment of the physical model of the flow of the entrance area, the water surface profile and flow velocity verification, reach and prototype similar requirement, the model can accurately reflect the river water flow motion characteristics test. Under the original proposal for the layout and approach channel river type and topography, etc., for a multi-program comparative test.The results of this study show that, because of Xijin Second-lane Shiplock upper approach entrance area at the bend upstream reach, approach channel axis and the angle between the larger mainstream, resulting in the entrance area there exists strong cross; at the same time in the channel formed within a large range of return, when the inflow is larger (Q>9122m3/s) brake release flood waters, all open drain, original design approach entrance area of longitudinal, transverse and return flow rate exceeded the standard allowable value. Model through several test schemes are compared:take longer water wall and adjustment of excavation line measures, so that the approach channel, flow condition gets clear improvement, in the flow of Q=9122m3/s, in addition to individual points, the speed indicators are able to meet the requirements of the relevant regulations.The results of this study show that, Xijin lock lower approach channel arranged in the river bend near the top, flow condition of second-lane lock downstream entrance area will be affected greater. But through Adjusted approach channel arrangement, extended the interval partition length of the first and second, changed the flow direction, improved the second-lane lock the entrance area of the flow pattern, the entrance area navigation flow targets to meet the basic specifications.