發(fā)布時間：2018-05-15 00:41

  本文選題：能量分析 + 應(yīng)變能密度��； 參考：《中國礦業(yè)大學(xué)》2015年碩士論文

【摘要】：巖石的變形破壞過程始終伴隨著能量的轉(zhuǎn)化和轉(zhuǎn)移,地下工程圍巖體變形失穩(wěn)過程中能量的變化也貫穿其中,支護(hù)體的施加對圍巖體的變形失穩(wěn)具有一定的抑制作用,對圍巖內(nèi)能量的轉(zhuǎn)化和轉(zhuǎn)移也必定存在影響。因此,分析地下工程圍巖體在支護(hù)作用下能量的變化特性,可為巷道圍巖支護(hù)理論和支護(hù)設(shè)計提供指導(dǎo)。根據(jù)最低能量原理,任何體系在處于最低能量狀態(tài)時是最穩(wěn)定的�；诖�,本文首先采用理論分析的方法,以Mohr-Coulomb屈服準(zhǔn)則為依據(jù),從能量角度分析圓形巷道開挖后巷道圍巖內(nèi)塑性應(yīng)變能和總能量在圍巖中的分布情況及其影響參數(shù),以及主要影響參數(shù)之間的協(xié)同匹配效應(yīng);其次,以圍巖能量為評判標(biāo)準(zhǔn),采用數(shù)值模擬方法,分析錨桿與錨索支護(hù)參數(shù)之間的協(xié)同匹配效應(yīng)。本文獲得以下主要結(jié)論:(1)針對圓形巷道,推導(dǎo)圍巖內(nèi)總能量密度和彈性能密度分布公式,獲得圍巖總能量密度和彈性能密度的變化和分布規(guī)律。(2)通過分析巷道開挖后圍巖能量分布特征,發(fā)現(xiàn)根據(jù)塑性位勢理論得到的位移分布式不適用于塑性區(qū),由此位移所求塑性區(qū)總能量在部分范圍內(nèi)小于圍巖彈性能,違背能量守恒定律。(3)影響圍巖彈性能和塑性能的敏感因子是原巖力學(xué)參數(shù)和原巖應(yīng)力,其中,粘聚力相比于內(nèi)摩擦角對破碎區(qū)圍巖能量影響較大,提高彈性模量可有效減少破碎區(qū)圍巖內(nèi)的能量;增強(qiáng)支護(hù)力可以增加圍巖的彈性能,同時減少破碎區(qū)圍巖的塑性破壞能及其集聚程度,有利于圍巖穩(wěn)定。(4)增加錨桿預(yù)緊力可以增大巖體的粘聚力,粘聚力的增加可以減少破碎區(qū)范圍,但會加劇塑性能的集聚,需要配以組合錨索為圍巖提供均布支護(hù)力,減弱圍巖塑性能集聚程度;而粘聚力和支護(hù)力的增加會提高圍巖的彈性能,需要配以高彈性模量的錨桿、錨索,增加整體的彈性模量,減少圍巖的彈性能和位移,使巷道圍巖處于少破碎、均勻破碎和低能量的穩(wěn)定狀態(tài)。(5)錨索預(yù)緊力是圍巖能量的敏感因子,而錨索長度對圍巖能量沒有影響,考慮到錨固段附加拉應(yīng)力場對巷道附近圍巖能量的波及,常規(guī)條件下錨索長度應(yīng)在5m~7.5m之間。(6)組合錨索的支護(hù)效果優(yōu)于單體錨索,且錨索預(yù)緊力和錨索間距之間存在協(xié)同匹配效應(yīng),在錨索預(yù)緊力較小時需減小錨索間距,而較大的錨索預(yù)緊力可適當(dāng)增加錨索間距。(7)支護(hù)的目的不僅僅是控制圍巖的變形、提高圍巖強(qiáng)度,而是在盡可能減少巷道附近圍巖塑性破壞能及其集聚程度的前提下提高破壞后圍巖的穩(wěn)定性。
[Abstract]:The process of rock deformation and failure is always accompanied by the transformation and transfer of energy, and the change of energy in the process of deformation and instability of surrounding rock mass of underground engineering also runs through it, and the application of supporting body can restrain the deformation and instability of surrounding rock body to a certain extent. The transformation and transfer of energy in surrounding rock must also be affected. Therefore, the analysis of the energy variation characteristics of surrounding rock mass in underground engineering under the action of support can provide guidance for the supporting theory and design of roadway surrounding rock. According to the principle of minimum energy, any system is the most stable in the lowest energy state. Based on this, the distribution of plastic strain energy and total energy in surrounding rock of circular roadway after excavation and its influence parameters are analyzed from the angle of energy, based on Mohr-Coulomb yield criterion. Secondly, the synergetic matching effect between anchor and cable support parameters is analyzed by numerical simulation based on the energy of surrounding rock. In this paper, the following main conclusions are obtained: (1) for circular roadway, the distribution formulas of total energy density and elastic energy density in surrounding rock are derived. The variation and distribution of total energy density and elastic energy density of surrounding rock are obtained. (2) by analyzing the energy distribution characteristics of surrounding rock after tunnel excavation, it is found that the displacement distribution obtained from plastic potential theory is not suitable for plastic zone. The total energy of the plastic zone obtained by displacement is smaller than the elastic energy of surrounding rock in some extent, and the sensitive factor affecting the elastic energy and plastic properties of surrounding rock is the mechanical parameter and stress of the original rock, which violates the law of conservation of energy. Compared with the angle of internal friction, the cohesive force has a greater influence on the energy of the surrounding rock in the broken area, and the increase of the elastic modulus can effectively reduce the energy in the surrounding rock of the broken area, and the strengthening of the supporting force can increase the elastic energy of the surrounding rock. At the same time, reducing the plastic failure energy and gathering degree of the surrounding rock in the broken area, which is beneficial to the stability of the surrounding rock, increases the pretightening force of the anchor rod can increase the cohesion of the rock mass, and the increase of the cohesion force can reduce the area of the broken area, but it will aggravate the accumulation of the plastic properties. It is necessary to use combined anchor cables to provide uniform supporting force for surrounding rock, to weaken the accumulation degree of surrounding rock plastic properties, and the increase of cohesion and support force will improve the elastic performance of surrounding rock, and the anchor cable with high elastic modulus is needed. Increasing the elastic modulus of the whole, reducing the elastic energy and displacement of the surrounding rock, making the surrounding rock of the roadway in the condition of less breakage, uniform breakage and stable state of low energy, the pretightening force of the anchor cable is the sensitive factor of the energy of the surrounding rock. However, the length of anchor cable has no effect on the energy of surrounding rock. Considering the effect of additional tensile stress field of anchor section on surrounding rock energy near roadway, the support effect of combined anchor cable should be better than that of single anchor cable under conventional conditions. Moreover, there is a synergistic matching effect between the pre-tightening force of anchor cable and the distance between anchor cables. When the pre-tension force of anchor cable is small, the distance between anchor and cable should be reduced, but the larger pre-tightening force of anchor cable can increase the distance between anchor cable and cable appropriately. The purpose of supporting is not only to control the deformation of surrounding rock, but also to control the deformation of surrounding rock. In order to improve the strength of surrounding rock, the stability of surrounding rock is improved on the premise of reducing the plastic failure energy of surrounding rock near roadway and its accumulation degree as far as possible.
【學(xué)位授予單位】：中國礦業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TD353

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 范宇潔;萬勝武;;預(yù)應(yīng)力錨索有效錨固長度和極限抗拔力的計算[J];地下空間與工程學(xué)報;2006年04期

2 王文時，孫新平;對原子體系的最低能量原理表述的分析[J];大學(xué)物理;1994年10期

3 于海軍;陳智強(qiáng);姜春雨;;深埋長大隧道圍巖破壞能量釋放數(shù)值模擬[J];遼寧工程技術(shù)大學(xué)學(xué)報(自然科學(xué)版);2011年05期

4 李元;劉剛;龍景奎;;深部巷道預(yù)應(yīng)力協(xié)同支護(hù)數(shù)值分析[J];采礦與安全工程學(xué)報;2011年02期

5 劉剛;龍景奎;劉學(xué)強(qiáng);李元;;巷道穩(wěn)定的協(xié)同學(xué)原理及應(yīng)用技術(shù)[J];煤炭學(xué)報;2012年12期

6 田雨貴;物質(zhì)的結(jié)構(gòu)、性質(zhì)與能量最低原理[J];雁北師范學(xué)院學(xué)報;2002年05期

7 華安增;地下工程周圍巖體能量分析[J];巖石力學(xué)與工程學(xué)報;2003年07期

8 趙陽升,馮增朝,萬志軍;巖體動力破壞的最小能量原理[J];巖石力學(xué)與工程學(xué)報;2003年11期

9 張友葩,高永濤,吳順川;預(yù)應(yīng)力錨桿錨固段長度的研究[J];巖石力學(xué)與工程學(xué)報;2005年06期

10 彭瑞東;謝和平;鞠楊;;砂巖拉伸過程中的能量耗散與損傷演化分析[J];巖石力學(xué)與工程學(xué)報;2007年12期

，

本文編號：1890223