【摘要】：埋地管道作為一種安全、經(jīng)濟、高效的運輸方式已大量應(yīng)用于天然氣遠程運輸行業(yè)。隨著我國高鐵化進程的實施,在進行隧道爆破掘進施工時產(chǎn)生的爆破振動必然會對臨近埋地管道周圍的地層產(chǎn)生擾動,給埋地管道的安全運行帶來威脅。而天然氣管道一旦發(fā)生事故(破裂、爆管或滲漏),除了管道系統(tǒng)自身的損壞造成的直接損失之外,還可能引發(fā)嚴重的次生災(zāi)害,引起火災(zāi)或者爆炸,甚至造成人員傷亡。在建的西安至成都客運專線仙女巖隧道下穿蘭-成-渝埋地天然氣管道,在隧道掘進施工過程中產(chǎn)生的爆破振動可能危及隧道上方埋地天然氣管道的安全運行。為確保天然氣管道的安全運行,分析爆破振動對埋地管道的影響程度,本文以隧道減震控制爆破的實時振動監(jiān)測為基礎(chǔ),采用數(shù)值模擬方法進行爆破振動作用下埋地天然氣管道的動力響應(yīng)研究,主要分析在不同埋地天然氣管道運行工況條件下管道的動應(yīng)力分布特征及其變化規(guī)律。隧道施工過程中采用減震控制爆破技術(shù)降低爆破產(chǎn)生的振動效應(yīng),在進行的27次現(xiàn)場爆破中,監(jiān)測到的埋地天然氣管道上方地表的振動強度基本上未超過管道安全運行規(guī)定的2cm/s的峰值振動速度要求,保證了天然氣管道的安全、正常運行。通過分析隧道開挖減震控制爆破的地表振動速度波形的特征參數(shù)發(fā)現(xiàn),埋地天然氣管道上方地表的爆破地震波具有頻率高、衰減快、持續(xù)時間短的特點,在與爆破中心相距40-60m范圍內(nèi)的振動速度波形的主頻多大于20Hz、持續(xù)時間一般在1秒以內(nèi)。以仙女巖隧道下穿埋地天然氣管道段的爆破施工為背景,參照天然氣管道的敷設(shè)規(guī)范,建立爆破振動下埋地天然氣管道的三維有限元模型,通過模擬計算結(jié)果與現(xiàn)場實測振動數(shù)據(jù)的對比分析,既檢驗?zāi)M計算結(jié)果的準確性,又進一步修改完善模型參數(shù)。以管道振動應(yīng)力為研究對象,進行不同管道運行工況下的埋地天然氣管道的動力響應(yīng)分析,包括：不同管道內(nèi)壓、不同管上之間摩擦系數(shù)和不同管徑等條件下爆破振動引起的埋地天然氣管道的應(yīng)力分布狀態(tài),探討天然氣管道工況參數(shù)對埋地管道動力響應(yīng)的影響規(guī)律。研究證明：在爆破作用下,埋地管道頂部應(yīng)力最大；最大應(yīng)力隨著內(nèi)壓的增大而增大；管土之間摩擦系數(shù)越大,管道的應(yīng)力越大；增大管徑,管道的應(yīng)力減小。
[Abstract]:As a safe, economical and efficient transportation mode, buried pipeline has been widely used in natural gas long-distance transportation industry. With the implementation of the process of high-speed iron in China, the blasting vibration generated during the tunneling construction will inevitably disturb the strata around the buried pipeline and threaten the safe operation of the buried pipeline. In the event of an accident (rupture, burst or leakage) of natural gas pipeline, in addition to the direct loss caused by the damage of the pipeline system itself, it may also cause serious secondary disasters, fire or explosion, and even cause casualties. Under the Xianyan Tunnel of Xi'an to Chengdu passenger dedicated Line, the natural gas pipeline buried in Lanzhou-Chengdu-Chongqing is under construction. The blasting vibration generated during tunneling may endanger the safe operation of buried natural gas pipeline above the tunnel. In order to ensure the safe operation of natural gas pipeline and analyze the influence of blasting vibration on buried pipeline, this paper is based on the real-time vibration monitoring of tunnel vibration control blasting. The dynamic response of buried natural gas pipeline under blasting vibration is studied by numerical simulation method. The dynamic stress distribution and its variation law of buried natural gas pipeline under different operating conditions are analyzed. In the course of tunnel construction, the vibration effect caused by blasting is reduced by using shock absorption control blasting technology. In 27 field blasting, The vibration intensity of the surface above the buried natural gas pipeline is basically not higher than the peak vibration speed of 2cm/s stipulated by the safe operation of the pipeline, which ensures the safety and normal operation of the natural gas pipeline. By analyzing the characteristic parameters of the surface vibration velocity waveform of the tunnel excavation controlled blasting, it is found that the blasting seismic wave above the buried natural gas pipeline has the characteristics of high frequency, fast attenuation and short duration. In the range of 40-60 m from the blasting center, the main frequency of the vibration velocity waveform is more than 20 Hz, and the duration is generally within 1 second. Under the background of blasting construction of gas pipeline under Xianyan tunnel, a three-dimensional finite element model of buried natural gas pipeline under blasting vibration is established according to the laying code of natural gas pipeline. Through the comparison and analysis between the simulation results and the field measured vibration data, the accuracy of the simulation results is verified, and the model parameters are further modified. The dynamic response of buried natural gas pipeline under different operating conditions is analyzed by taking the vibration stress of pipeline as the research object, including: internal pressure of different pipeline, The stress distribution state of buried natural gas pipeline caused by blasting vibration under the condition of friction coefficient and different pipe diameter between different pipes is discussed in this paper. The influence of operating conditions parameters of natural gas pipeline on dynamic response of buried pipeline is discussed. The results show that the maximum stress at the top of buried pipeline increases with the increase of internal pressure, the greater the coefficient of friction between pipes and soil, the greater the stress of pipeline; the greater the diameter of pipe, the smaller the stress of pipeline.
【學(xué)位授予單位】：西南交通大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TE973

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1 趙長嘯;龍源;紀沖;路亮;高福銀;廖昆;;土中爆炸沖擊作用下埋地管道動力響應(yīng)數(shù)值模擬研究[A];中國爆破新技術(shù)Ⅲ[C];2012年

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本文編號：2171694