【正文】 s, ., Thompson, ., Jones, ., Wang, A.: Calculation of noise from railway bridges and viaducts: Experimental validation of a rapid calculation model. Journal of Sound and Vibration 293, 933–943 (2021) [2] Janssens, ., Thompson, .: A calculation model for the noise from steel railway bridges. Journal of Sound and Vibration 193, 295–305 (1996) [3] Harrison, ., Thompson, ., Jones, .: The calculation of noise from railway viaducts and bridges. Proc. Institution Mechanical Engineers, Part F (Journal of rail and rapid transit) 214, 125–134 (2021) [4] Thompson, ., Hemsworth, B., Vincent, N.: Experimental validation of the TWINS prediction program for rolling noise, part 1: Description of the model and method. Journal of Sound and Vibration 193, 123–135 (1996) [5] Thompson, ., Jones, .: A review of the modelling of wheel/rail noise method. Journal of Sound and Vibration 231(3), 519–536 (2021) [6] Bewes, O., Thompson, ., Jones, .: Calculation of noise from railway bridges: The mobility of beams at high frequencies. Structural dynamics: Recent advances. In: Proceedings of the 8th International conference, Institute of Sound and Vibration Research, Southampton, (paper 64 on CD ROM) July 14–16 (2021) [7] Jones, ., Thompson, .: Acoustic analysis of Burgdorf bridge, ISVR contract report no 06/03, University of Southampton (2021) [8] Jones, ., Thompson, ., Diehl, .: The use of decay rates to analyse the performance of railway track in rolling noise generation. Journal of Sound and Vibration 293(3–5), 485–495 (2021) [9] Janssens, ., Dittrich, ., de Beer, ., Jones, .: Railway noise 畢業(yè)設計外文文獻及譯文 12 measurement method for passby noise, total effective roughness, transfer functions and track spatial decay. Journal of Sound and Vibration 293(35), 1007–1028 (2021) [10] Bouvet, P., Vincent, N., Coblenz, A., Demilly, F.: Optimisation of resilient wheels for rolling noise control. Journal of Sound and Vibration 231(3), 765–777 (2021) [11] Muff, W., Grolimund amp。 (a) north track。? (b) south track ( Fax: +41 (0)51 220 5014 2 University of Southampton, ISVR, Highfield Southampton, SO17 1BJ, Southampton, UK Tel.: +44 (0) 2380 593224。 right side, decay rates of the rail. An estimation of the bined effective roughness (. bined wheel and rail roughness with the contact filter already accounted for) is needed for the predictions. A method to determine the bined roughness from rail vibration measurements under traffic is described in reference [9]. This method uses the spectrum of vibration during a train passby and three correction factors. It has been applied to rail vibration measured by the SBB. The roughness is a function of the brake type of the train. Here, the most important trains to consider are the cast iron block treadbraked freight trains. Two measurements of vertical rail vibration are available from trains travelling at steady speeds of 77km/hr and 72km/hr. Three more are available for lower speeds that vary during the measurements from about 40 to 60km/hr. The estimates of the bined effective roughness from these records are presented in Fig. 3. They are plotted as a function of frequency corresponding to a train speed of 100km/hr. These roughness spectra are plotted in parison with the typical spectra for smooth rail and either cast iron block treadbraked, or discbraked trains. These are the standard roughness spectra used in the Silent Freight and Silent Track EU projects [10]. The roughness assumed for the present calculations is also shown on Fig. 3. 畢業(yè)設計外文文獻及譯文 7 Fig. 3. Combined effective roughness spectra derived from measurements pared with those used in the Silent Freight and Silent Track Projects (──, calculated from the two faster freight trains。 , predicted after, rmmessungen vor und nach der Sanierung, Bern (2021) et al.(Eds.):Noise and Vibration Mitigation,NNFM99,2021. 169。 因此，由瑞士鐵路（國鐵）在雙軌的橋梁上對兩種不同的鋼軌扣件進行了測試。然而，如模型所示，在 A 加權的總噪聲水平下降的范圍是在 2 至 4 分貝。重建與噪聲測量進行于 5 月， 10 月， 12 月 6 日和 1 月 7 日。 2 建模 ISVR 開發(fā)了橋梁噪聲預測模型諾伯特，該模型以一個對軌道的分析模型和一個橋梁統(tǒng)計能量分析法的 [2， 3]（ SEA）組合為基礎。車輪與軌道發(fā)出滾動畢業(yè)設計外文文獻及譯文 15 噪聲的模型被完美確立 [4， 5]。 就布格多夫大橋而言，鋼枕木將對軌道噪聲衰減率有顯著影響，并為其提供一個額外的散熱元件。在衰退率的測量中，遠達 米激 發(fā)距離已被使用。它已被 SBB 應用到鐵路的振動的測量。這些是用于歐盟無聲貨運和無聲軌道項目 [10]中的標準粗糙度光譜。測量的詳情，記載于一份瑞士鐵路報畢業(yè)設計外文文獻及譯文 17 告 [11]中。 在每個例子中，測量是在 66到 72km/hr行駛的貨運列車的平均水平。被主測 800 赫茲以下的 Twins 模型所確定的來自枕木的噪聲，在這種情況下被碎石影響，并且地面反射預計在相當程度上被吸收。對旅客列車測量的平均值 。結果表明，因底板而達到的 80至 400Hz范圍內的減少被鋼枕木損害了約 2至 3分貝。這導致貨運與客運列車的整體噪聲降低水平僅為約 3分貝（預測值為 4 分貝）。 SpringerVerlag Berlin Heidelberg2021 1:46 102 機體齒飛面孔雙臥多軸組合機床及 CAD 設計 09/08 20:02 3kN 微型裝載機設計