In view of the questions for the rock anchor foundation used in the actual transmission line project, and the need to provide the supporting capacity, the bond strength between anchor bar and concrete and so on for the rock anchor foundation design, loading test was carried out for real foundations in working conditions of the vertical uplift or the three-directions loading. Based on the model failure manifestation of foundations, the load-displacement relations, the anchor bar strain-buried depth relations and so on, have analyzed the main failure state and the load-supporting characteristics, as well as the anchor bar transmission load characteristic. The findings indicated that the rock anchor foundation may be used in the medium and strong weathered rock distribution region, and has the good economy and the social efficiency. There is an obvious first inflection point in the load-displacement curves, corresponding to the displacement of less than 10mm. the higher degree of weathered bedrock is, the smaller foundation bearing capacity is, and the greater displacement is. And the horizontal load has the adverse effect to uplift stability the group anchor foundation.
This paper analyzes the text knowledge expression technology, introduces the state space method, two aspects of value method, and production system, constitutes the ice situation grade standard according to text rules, which measures the ponderance of the ice situation. Obtains a new set of rules by extracting text metarules, selecting control strategy, eliminating rules conflict ,and integrating rules. On the state space method ,deals rules with grade standard and two aspects of value method ,and get a new set of rules described in numbers and symbols. In the VFP software platform, achieves decision-making of the implement condition about different types of ice-melting and de-icing methods through program.
220kV Taiyuan-Tazhong electric transmission line entered the Takla Makan desert center, and passed by area covered aeolian sand. the ordinary cast-in-place reinforced concrete foundation use faced with some problems, for example the foundation matter transport intense, the water source deficient. Through the strength calculation and contrastive analysis of foundation materials, the assembly foundation which made up of the reinforced concrete plank and the steel bracket unify was a safe and economical choice. Assembly foundation prototype tests had been done in the engineering pass-by area, according to analysis on test results, proposed the foundation supporting capacity and the component strength calculation method, obtained some key design variables including uplift angle and horizontal load influence coefficient. This pattern foundation has been used in the engineering, indicated that use of assembly foundation saved 15% of the investment in cast-in-place foundation, reduced the construction time, had obtained good economy and social efficiency, and had provided the important reference for the similar project's application.
The galloping is a critical threat to the security of power transmission lines. It will develop enormous social and economic value by researching the anti-galloping technology. The paper analyzes the characteristics of detuning pendulums and proposes a new type of anti-galloping model based on self-excited torsional oscillation mechanism. The model can contain galloping by inhibiting self-excited torsional oscillation. With this proposed model, simulation for one operational 110kV power transmission line is performed to demonstrate the rationality of the model and effect on anti-galloping.
Sag of transmission line is one of the main indexes for circuit design, running and maintenance. It directly impacts on the safety of the operation. Analyzing the hanging state of overhead power line between the two towers, the overhanging state of line can be determined by an independent variable when the span length is certain. By analyzing the sectional power line image, the independent variable can be extracted and the aclinic catenary can be restored based on the catenary-segment. Then the sag would be calculated. Both two end contour line and non-contour line are simulated by the method. And the experiment had indicated that it is efficacious.
Because of the limit of the structure and the environment of the power cable, it is very difficult to raise the capacity of the cable. In order to solve such problems, it is necessary to use the special measures to increase the capacity of cable. Although there are many measures to expand the capacity, using the water cooling system is the comparably cheap, effective technique. This paper analyses the water cooling system of cable in the tunnel, the result of analysis indicates that the cooling system will raise the capacity notably and it has the practical value in the project. On the other hand, the paper discusses not only the composition and space of the cooling system, but also the running and maintenance of the system. All results of this paper can be used as the technical reserves for the practical application.
Withstanding characteristics of several typical control cables under 50Hz AC, DC and lightning impulse overvoltage are tested and studied, results show that surface discharge voltage of cable terminal tends to saturate with the increase of pole distance; it have great effect on the withstanding characteristic of control cables that head and shield of its are treated well or not; the insulating property between shield and core wires is the most unsubstantial link in the whole insulation of control cables, it can withstand more than 18kV 50Hz AC voltage, 45kV positive DC voltage and 40kV negative lightning impulse voltage in 30 seconds. The grounding potential rise of grounding network should be controlled under their tolerance range in actual project.
According to our country’s policy of Energy Saver and Exhaust Reducer and oliymipic Security ,this article studied about environmental protection facilities in thermal power plant and real-time1 monitoring system of flue gas pollutant emissions. Collecting the environmental protection facilities of electric enterprises and Producing data of coal-fired power , these data have been transmited by private data network in electric power dispatching ,and been used real-time monitoring all of the data of flue gas pollutant emissions 0f coal-fired power for in Southern Hebei Power Network, and real-time monitoring the motion condition of environmental protection facilities .these data give some support to environmental protection organization to surveillance to flue gas control facilities’s function ,and give some support to coal-fired power’s electric quantity of desulfuration and the adjustion accounts of electricity price of desulfuration . This study about Real-time monitoring system decrease the monitoring system of flue gas pollutant and reduce the environment pollution of electric enterprises.
Based on analyzing the MOA various electrical properties of the basic parameters of the physical，discussing the factors which affect the accuracy of MOA test data，this article has explained how to estimate the MOA electrical properties based on the data from all kinds of testing. In addition, this paper has been discussed and summarized the way of judgment MOA performance is energized testing combined with the de-energized testing, and comprehensive analysis all the test data is accurate and reliable method to judge MOA condition.
Focusing analysis on the phenomenon of "gypsum rain" of the thermal power plant wet desulphurization process,and put forward the methods to solve the problems and suggestions from the FGD system design and operation etc,thus greatly reducing wet desulfurization "gypsum rain" phenomenon.
Abstract: The AP1000reactor coolant system consists of two heat transfer circuits, each with a steam generator and two reactor coolant pumps under the channel of generator. It introduce the main parts of AP1000 canned pump, analysis the advantages and disadvantages of application in nuclear power station, state the challenges which pump will face in manufacturing, motor cooling, reliability and availability.
The main reason of choosing self-shunt brushless excitation System in nuclear power station is firstly introduced in this paper，and the structure & function of brushless excitation system are analyzed, the characteristic of flashing excitation and boosting excitation are emphasized, rotor one-point earthing protection and other protection for excitation circuit are analyzed, and the method of de-excitation characteristic is described, self-shunt Brushless Excitation System is suitable for high capacity unit，it will has broad application in nuclear power station.
