自走铁矿破碎岩体巷道的支护研究与应用

发布时间：2018-03-12 21:58

  本文选题：破碎岩体　切入点：应力　出处：《昆明理工大学》2016年硕士论文　论文类型：学位论文

【摘要】：随着矿业工程的日益发展,在巷道掘进过程中由于支护不当而造成的安全事故不断增加,虽然国内外学者对此付出了大量心血,但由于工程岩体的复杂性,目前仍然没有一种统一的理论可以很好的适用岩体的支护。本文以云南自走铁矿1530中段局部破碎岩体,稳定性较差的岩体为主要研究对象,通过理论研究,现场调查,试验研究,数值模拟等多方面手段对云南自走铁矿1530中段岩体的支护方案进行研究,主要工作如下：(1)对云南自走铁矿1530中段岩体的完整性和结构面条件进行现场调查,统计数据。运用RMR岩体稳定性分级,我国工程岩体稳定性分级两种评价方法对云南自走铁矿1530中段岩体进行岩体稳定性分级,最终确定云南自走铁矿1530中段局部岩体为Ⅳ岩体,较坚硬岩,岩体较破碎-破碎。(2)通过对云南自走铁矿1530中段岩体进行现场取样,将岩样加工成试验试件,并对试验试件进行单轴压缩,劈裂,声发射试验,分析岩石在试验过程中的力学性能和声发射特性。最后得出1530中段石灰岩的平均单轴抗压强度为72MPa,平均抗拉强度为6MPa。石灰岩的声发射特性为累计AE数,AE累计振铃数,AE累计能量在加载初期出现快速增长,说明石灰岩内部,外部孔隙,裂隙较多较为破碎。累计AE数,AE累计振铃数,AE累计能量在加载后期出现高速增长,说明石灰岩发生塑性变形直至破坏。(3)根据确定的混凝土配合比,实验室浇筑,养护混凝土试块,并通过单轴压缩试验对1%,2%,两种不同比例的钢纤维在7d,14d,28d三个养护周期的单轴抗压强度与素混凝土7d,14d,28d三个养护周期的单轴抗压强度进行对比,从而分析加入不同比例的钢纤维在7d,14d,28d三个养护周期混凝土强度的变化规律。(4)云南自走铁矿1530中段局部较为破碎,稳定性较差部位采用超前小导管注浆支护,钢纤维喷射混凝土和锚杆联合支护,巷道施工作业方式采用三八作业制,一掘一支,巷道掘进后立即进行钢纤维喷射混凝土,树脂锚杆联合支护,巷道局部地压较大,变形较大部位采用拱形工字钢支架,立模板浇筑混凝土进行支护,此段巷道要及时,加强支护。巷道稳定性较好区域先采用单一临时钢纤维喷射混凝土支护,后采用永久钢纤维锚喷联合支护,二次支护,巷道作业方式采用三八作业制,两掘一支,一天掘进两个循环进尺,一般向前掘进4m,根据现场经验,在软岩支护中控顶距一般不超过40m,而自走铁矿1530中段石灰岩属于较坚硬岩,不属于软岩,所以控顶距我选择20m(即第二次永久支护距掘进断面之间的距离最大不能超过20m)也就是最晚在钢纤维喷射混凝土临时支护作业后的第5天就要进行第二次钢纤维喷射混凝土支护,并且在前段掘进过程中,观测后段围岩支护效果,如果后段钢纤维喷射混凝土支护效果不好,再缩短控顶距。由于此段巷道稳定性较好,所以要充分发挥围岩自身的稳定性,做到先柔后让。(5)运用MIDAS数值模拟软件对云南自走铁矿1530中段局部破碎,稳定性较差的岩巷进行掘进后数值模拟,支护后数值模拟,最终确定采用钢纤维锚喷支护,底板浇筑混凝土联合支护后巷道围岩顶板位移为0.006m,底板位移为0.007m,两帮位移为0.003m,巷道围岩变形控制在允许范围内,支护效果较好。
[Abstract]:With the increasing development of mining engineering, safety accidents in tunnel excavation process due to improper support increasing, although domestic and foreign scholars have paid a lot of effort, but because of the complexity of engineering rock mass, for rock mass is still not a unified theory can be a very good support. This paper takes Yunnan self walking the middle of the 1530 local iron ore rock mass and rock mass stability as the main object of study, experimental research through theoretical research, field investigation, numerical simulation, many methods to study in Yunnan since the middle of 1530 iron go rock supporting scheme, the main work is as follows: (1) the on-site survey, the integrity and structure of Yunnan since iron ore 1530 middle rock surface conditions using statistical data. The stability of rock mass classification of engineering rock mass RMR, the stability of China's classification of two kinds of evaluation methods of Yunnan since iron ore 1530 Some rock rock classification, and ultimately determine the Yunnan auto iron 1530 middle local rock mass in fourth rock, hard rock, rock is broken broken. (2) in Yunnan since 1530 middle iron ore rock scene will be sampling, specimen test, and the test specimen subjected to uniaxial compression, fracturing, acoustic emission test, and the mechanical properties of rock in the process of test of emission characteristics analysis. Finally the 1530 middle limestone average uniaxial compressive strength is 72MPa, the average tensile strength of 6MPa. limestone acoustic emission characteristics for the cumulative number of AE, AE accumulated counts, AE accumulated in the early stage of loading the rapid growth of energy that, the internal and external pore fractured limestone, and more is broken. The cumulative number of AE, AE accumulative number, AE cumulative energy in the loading stage the fast growth, indicating the limestone plastic deformation and failure of root (3). According to the concrete mix, pouring concrete laboratory, maintenance, and through uniaxial compression tests on 1%, 2%, two different proportions of steel fiber in 7d, 14d, uniaxial compressive strength 28d three maintenance cycle and plain concrete 7d, 14d, comparing the uniaxial compressive strength of three 28d the maintenance cycle, so as to analyze the steel fiber with different proportions in 7d, 14d, 28d changes three curing period of concrete strength. (4) in Yunnan since the 1530 local middle go iron ore is broken, poor stability of parts of the use of advanced small pipe grouting support, steel fiber shotcrete and bolt support, the way of roadway construction operation with 38 operating system, a dig a tunnel, immediately after the steel fiber sprayed concrete, resin bolt support roadway, local pressure large, large deformation parts adopt arched steel support formwork, pouring concrete Soil supporting, the tunnel should be timely, strengthen the supporting roadway stability is better. The regional single temporary steel fiber shotcrete, the permanent steel fiber shotcrete combined support, two support, tunnel operation using 38 operating system, two driving a day, driving two the general circulation footage, driving 4m, according to the experience, in support of soft rock in roof control distance is generally not more than 40m, and since the middle of 1530 iron limestone belongs to go hard rock, do not belong to the soft rock, so the roof distance I choose 20M (i.e. second permanent support from the heading section the maximum distance between the not more than 20m) is the latest in steel fiber shotcrete temporary supporting operation after fifth days to second times of steel fiber shotcrete, and in front of the tunneling process, after the observation section of surrounding rock supporting effect, if the rear section of the steel fiber sprayed concrete Soil retaining effect is not good, then shorten the roof distance. Because of the stability of roadway is better, so we should give full play to the stability of the surrounding rock itself, so that the first soft after. (5) using MIDAS numerical simulation software of Yunnan iron ore in the middle 1530 local self broken, poor stability in the numerical simulation of rock roadway excavation a numerical simulation, support, and ultimately determine the use of steel fiber shotcrete, concrete pouring floor joint after supporting roof surrounding rock displacement of roadway is 0.006m, the floor displacement was 0.007m, two for displacement is 0.003m controlled within the allowable range of deformation of roadway, the supporting effect is good.

【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TD353
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本文编号：1603467