Research On The Characteristic Of Tianjin Beachfront Sea-current, Waves And Tide

Tianjin lives in the top of the Bohai bay, has 155 km. long coastline and 3 to 8 km.long tidal bank. The frontbeach is large, more than 10 mil. ac.. But the frontbeach iseasy to be attacked by the tide due to its low elevation. So the construction of thebreakwaters is an urgent work. The study of the hydrological parameter using indesigning breakwaters, becomes instant.The investigation is based on investigating the characteristic of beachfront oceancurrents, waves and tides in Tianjin. The result can offer the technical parametersusing in designing breakwaters and theoretical basis using in constructing economicalbreakwaters.1 The investigation offers theoretical basis and technical services for designingand constructing breakwaters projects. The investigation is based on the parametersusing in constructing breakwaters projects, just like the elevation and type of thebreakwaters in different return period.2 By the way of analyzing, observing and experimenting the characteristic ofbeachfront ocean currents, waves and tides in Tianjin, the particular investigation andanalysis has been achieved.3 The simulation of beachfront tide in different return period(twenty-year,fifty-year, one hundred-year) has been carried out in the old and now observing data.The numerical model is based on the method of fictitious flow. The simulating resultsof eroding and filling up in different bank is compared with the experiment result andthe silt theory, they are accordant.4 By means of scene survey and numerical simulation, the distribution of theflow field in different working circs has been simulated, and the height of the tide indifferent return period has been calculated. The result is useful for confirming the topelevation of the bank in constructing the breakwaters. The empirical formula ofpredicting the development of wave in shore has been set up by means of prototypeobservation and statistical method. The bank of eroding and filling up has beenanalyzed and then confirmed based on the rose.5 The experimental plan of eroding before breakwaters and the configurationstabilization has been simulated in the condition of different working circs and waterlevel. The plan is based on the physical model experiment and the configuration typeof breakwaters. The distribution of wave pressure, the percussive speed from waveand the erode of sandiness seabed have been researched under the action of regularwave(broken and standing wave) and irregular wave.