本文選題：危巖塊體　切入點(diǎn)：安全評價(jià)　出處：《北京科技大學(xué)》2016年博士論文　論文類型：學(xué)位論文

【摘要】：邊坡危巖塊體的穩(wěn)定性問題是工程地質(zhì)和巖土工程兩大學(xué)科中的基本課題之一,近些年來,隨著經(jīng)濟(jì)的發(fā)展,交通、水利、能源工程的建設(shè),出現(xiàn)了大量的人工邊坡和被改造后的天然邊坡,危巖塊體失穩(wěn)破壞現(xiàn)象越來越多,給當(dāng)?shù)厝嗣竦纳?cái)產(chǎn)造成不可挽回的損失的同時(shí),也給公路、鐵路等交通運(yùn)輸安全帶來嚴(yán)重隱患。因此,對危巖破壞崩塌進(jìn)行研究,尤其是其穩(wěn)定性的分析判別對于地質(zhì)災(zāi)害防災(zāi)減災(zāi)領(lǐng)域具有極強(qiáng)的現(xiàn)實(shí)意義。危巖塊體的穩(wěn)定性主要取決于巖塊體本身與邊坡巖體的粘結(jié)程度,基于結(jié)構(gòu)動力學(xué)理論,粘結(jié)力的變化必然會引起巖體振動特性發(fā)生變化。論文以邊坡危巖塊體快速識別、安全評價(jià)及監(jiān)測預(yù)警為研究目標(biāo),主要研究固有振動頻率與危巖塊體穩(wěn)定性的動態(tài)關(guān)系模型,通過非接觸的遠(yuǎn)程激光測振方法與傳統(tǒng)傳感器的測試數(shù)據(jù)成果對比分析,建立基于動力特征參數(shù)的危巖塊體快速安全評價(jià)方法并進(jìn)行監(jiān)測預(yù)警方法研究。本論文分別從理論研究、實(shí)驗(yàn)?zāi)Ｐ团c現(xiàn)場應(yīng)用等方面對固有振動頻率與危巖塊體的安全穩(wěn)定性關(guān)系模型進(jìn)行研究,主要結(jié)論如下：(1)基于振動力學(xué)原理,建立固有振動頻率與粘結(jié)力理論關(guān)系模型,由模型可知,固有振動頻率的變化能夠反應(yīng)危巖塊體的粘結(jié)強(qiáng)度的變化,頻率分析能夠在第一時(shí)間反應(yīng)邊坡危巖塊體的損傷狀況。(2)通過理論模型研究,可以分析不同時(shí)刻抗滑力指標(biāo)的變化情況,并分析出邊坡危巖塊體破壞的三個(gè)階段：強(qiáng)穩(wěn)定階段、弱穩(wěn)定階段和破壞階段。(3)通過實(shí)驗(yàn)發(fā)現(xiàn),隨著潛在滑移面粘結(jié)力的減少,固有振動頻率從原有12.67Hz逐漸下降至4.67Hz,對粘結(jié)力指標(biāo)有很好的指示作用。隨著危巖塊體潛在滑移面粘結(jié)系數(shù)的降低,固有振動頻率會首先發(fā)生變化,在200-230s期間發(fā)生大幅度下降；而位移指標(biāo)則在220-230s時(shí)才發(fā)生相應(yīng)變化,基于固有振動頻率的最佳預(yù)警時(shí)段要早于位移預(yù)警20s。(4)由摩擦力預(yù)警實(shí)驗(yàn)可知,摩擦力指標(biāo)在強(qiáng)穩(wěn)定階段基本不發(fā)生作用,而在弱穩(wěn)定階段中逐漸增大并占據(jù)整個(gè)抗滑力的80%以上,最終達(dá)到最大靜摩擦力時(shí)產(chǎn)生破壞。實(shí)驗(yàn)中,以摩擦力是否達(dá)到最大摩擦力為破壞判別標(biāo)準(zhǔn),其預(yù)警時(shí)效性優(yōu)于位移預(yù)警30s。(5)通過監(jiān)測的固有振動頻率的變化來對極限平衡模型中的粘結(jié)力指標(biāo)進(jìn)行動態(tài)調(diào)整,并對極限平衡分析模型安全系數(shù)公式進(jìn)行修正,實(shí)驗(yàn)結(jié)論可知,基于粘聚力動態(tài)參數(shù)計(jì)算的安全系數(shù),與實(shí)驗(yàn)結(jié)果基本相符。(6)基于固有振動頻率與滑動面粘聚力關(guān)系模型,對三維極限平衡的4種理論模型公式進(jìn)行修正,計(jì)算結(jié)果顯示,經(jīng)過大雨等擾動后,邊坡危巖塊體的三維安全系數(shù)由原來的1.3下降到1.1,與實(shí)際觀察結(jié)果相符。(7)基于遠(yuǎn)程激光測振的應(yīng)用研究發(fā)現(xiàn),激光多普勒測振儀可實(shí)現(xiàn)固有振動頻率等動力特性指標(biāo)的遠(yuǎn)程監(jiān)測,通過與傳統(tǒng)傳感器的對比研究發(fā)現(xiàn)其在測量精度和損傷識別方面具有優(yōu)勢。(8)激光多普勒測振儀具備非接觸式、高敏感度和模糊識別等優(yōu)勢,在技術(shù)上可以快速測量邊坡危巖塊體的固有振動頻率。基于前期的實(shí)驗(yàn)研究和三維極限平衡模型,可對危巖塊體的安全系數(shù)進(jìn)行快速評價(jià),并可形成一套基于振動特性監(jiān)測為主、應(yīng)力應(yīng)變監(jiān)測和環(huán)境量監(jiān)測為輔的監(jiān)測預(yù)警方法。
[Abstract]:The problem of slope stability of dangerous rock mass is one of the basic problems of engineering geology and geotechnical engineering department in two universities in recent years, with the development of economy, traffic, water conservancy construction, energy engineering, the artificial slope and natural slope being transformed by the large number of dangerous rock mass failure phenomenon more and more, irreparable damage to the local people's life and property at the same time, but also to the highway, railway and other transportation safety have serious problems. Therefore, the destruction of the rockfall was studied, especially the very strong practical significance to distinguish the field of geological disaster prevention and mitigation is the analysis of the stability. The bonding degree of dangerous rock mass stability mainly depending on the rock mass and rock slope, based on the theory of structural dynamics, the change of adhesion will cause the vibration characteristics of rock mass change. The slope of rock block Rapid identification, safety evaluation and monitoring as the research object, mainly studies the dynamic relationship model of natural vibration frequency and rock block stability analysis results, comparing the test data through remote laser vibrometer non-contact method with traditional sensor, based on the rock block fast safety evaluation method of dynamic characteristic parameters and Study on monitoring and early warning methods. This paper from the theoretical research, study on safety and stability of the relationship model of natural vibration frequency and rock block of experimental model and field application, the main conclusions are as follows: (1) based on the principle of mechanical vibration, a natural vibration frequency and cohesion theory model, the model shows that the change of natural vibration frequency to change the bond strength of reaction of dangerous rock mass, frequency analysis can damage in the first time response slope rock block (2). Through the study of theoretical model can analyze the different time changes of anti slide force index, and analysis of the slope rock block failure in three stages: the strong weak stable stage, stable stage and failure stage. (3) found through experiments, with the reduction of the potential slip surface bond force, natural vibration frequency gradually from the original 12.67Hz dropped to 4.67Hz, is a good indication of bond index. With the decrease of rock block potential slip surface adhesion coefficient, natural frequency will first change occurs during 200-230s decreased significantly; and the displacement index in 220-230s is changed, the best early warning of natural vibration frequency to early period in the early warning based on 20s. displacement (4) by friction early-warning experiment shows that friction index in strong stable stage did not work, and in the weak stable stage gradually increases and occupy the entire anti slide More than 80% finally reached the maximum force and static friction force damage. In the experiment, in order to reach the maximum friction friction is as the failure criterion, the warning time is better than that of 30s. (5) warning displacement by changing the natural frequency of vibration monitoring to bond index limit equilibrium model in dynamic adjustment and the limit balance analysis model of safety coefficient formula is modified, the experimental results show that the calculation of safety factor of cohesion based on dynamic parameters, basically consistent with the experimental results. (6) the natural vibration frequency and sliding surface cohesion relation model based on 4 theoretical models on three dimensional limit equilibrium formula is modified, the calculation results show that after the heavy rain. After the disturbance, 3D safety factor of slope rock mass was reduced from 1.3 to 1.1, the results are consistent with the actual observation. (7) application of remote laser vibrometer based on the findings of, Laser Doppler vibrometer can realize remote monitoring of natural vibration frequency of the dynamic characteristics, compared with the traditional sensor and found that it has advantages in accuracy and damage identification. (8) laser Doppler vibrometer with non-contact, high sensitivity and fuzzy recognition and other advantages, can rapid measurement of natural frequency of slope rock block in technology. Experimental study and three-dimensional limit equilibrium model based on the previous, which can be used to quickly evaluate safety factor of rock block, and can form a set of vibration monitoring based on the main monitoring and early warning method for stress monitoring and environmental monitoring should be.

【學(xué)位授予單位】：北京科技大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2016
【分類號】：TU45

【相似文獻(xiàn)】

相關(guān)期刊論文 前7條

1 孫強(qiáng);張忠平;李春旺;喬艷江;趙文軫;;某型航空發(fā)動機(jī)銷釘式葉片固有振動頻率的有限元計(jì)算[J];應(yīng)用力學(xué)學(xué)報(bào);2006年03期

2 王震鳴,戴涪陵;正交各向異性的多層、夾層和加筋扁殼的彎曲、穩(wěn)定和振動[J];力學(xué)學(xué)報(bào);1983年05期

3 李鵬;聲波共振治癌設(shè)想[J];發(fā)明與創(chuàng)新;2003年04期

4 呂毅寧;呂振華;;焊點(diǎn)連接模型對結(jié)構(gòu)剛度的有限元模擬精度的影響分析[J];工程力學(xué);2009年10期

5 錢星博;;次聲波——世界恐怖地區(qū)的魔鬼殺手[J];小學(xué)科技;2003年05期

6 吳曉;;三線擺法測定轉(zhuǎn)動慣量的計(jì)算原理分析[J];振動與沖擊;2011年09期

7 ;[J];;年期

相關(guān)博士學(xué)位論文 前1條

1 杜巖;基于固有振動頻率的危巖塊體穩(wěn)定評價(jià)模型研究[D];北京科技大學(xué);2016年

相關(guān)碩士學(xué)位論文 前1條

1 顧曉龍;脫掛索道線路結(jié)構(gòu)布置優(yōu)化設(shè)計(jì)[D];重慶大學(xué);2014年

，

本文編號：1638066