沪昆高铁黄连山隧道光面爆破技术研究与应用

发布时间：2018-05-14 04:08

本文选题：光面爆破 + 浅埋　；参考：《昆明理工大学》2014年硕士论文

【摘要】：光面爆破是一种在岩体开挖轮廓线上布置一排间距小的平行炮孔,然后同时起爆这些装药少、采用不耦合装药结构的炮孔,相邻两炮孔连线上的岩石被贯穿,形成平整光滑断裂面的控制爆破技术。黄连山隧道为浅埋、超大断面的高铁双线隧道,围岩地质条件复杂,稳定性差,工程质量要求高。若采用普通爆破的方法,极易出现围岩脱落、冒顶或松石甚至坍塌现象,给掘进带来非常大的困难和安全隐患。本论文从爆破效果和施工安全的角度,采用理论分析、现场试验和数值模拟的方法对该隧道的光面爆破进行了系统的研究。首先,亲临黄连山隧道现场调研地质条件、爆破环境和工程要求等施工条件。其次,把周边孔间距、光爆层厚度和线装药密度作为影响光面爆破效果的主要因素,根据经验公式确定这3个因素的合理范围,对每个因素选取3个水平,运用正交试验法择优组合9组试验方案；对每一组方案进行3次现场试验,统计并综合评价其爆破效果,把半孔率、超欠挖量和残孔深度作为评价指标,运用多目标灰色局势决策理论从9组试验方案中决策出合理的光面爆破方案(周边孔间距50cm,光爆层厚度60cm,线装药密度0.27kg/m)；最后,运用ANSYS/LS-DYNA有限元软件对该方案进行数值模拟。从光爆层选择单排相邻两周边孔台阶建立模型并进行数值计算,分析等效应力的传播过程,并对相邻两周边孔中垂线上的特定单元等效应力大小进行了分析。该方案被投入工程应用后,取得了令人满意的爆破效果。根据质检部门统计的数据,平均超欠挖量控制在6-10cm,最大超欠挖量控制在15cm之内,半孔率达到了75%左右,炮孔利用率达到95%左右,拱顶下沉和拱墙水平收敛趋于稳定,确定该方案可以保证黄连山隧道的工程质量,可以为隧道施工人员提供安全的施工环境。
[Abstract]:Smooth blasting is a kind of blasting holes with small spacing arranged on the outline of rock mass excavation, and then detonating these holes with less charge at the same time. The holes with uncoupled charge structure are used, and the rocks on the line of adjacent two holes are cut through. The controlled blasting technique for forming smooth and smooth fracture surface. Huanglianshan Tunnel is a shallow tunnel with large cross section, which has complex geological conditions, poor stability and high engineering quality. If the common blasting method is adopted, it is easy to appear the phenomenon of surrounding rock falling off, roof falling or loose stone falling or even collapsing, which brings great difficulties and hidden dangers to the excavation. In this paper, the smooth blasting of the tunnel is studied systematically by theoretical analysis, field test and numerical simulation from the point of view of blasting effect and construction safety. First of all, the site of Huanglianshan Tunnel investigation geological conditions, blasting environment and engineering requirements and other construction conditions. Secondly, taking the distance between the peripheral holes, the thickness of the blasting layer and the density of the line charge as the main factors affecting the effect of smooth blasting, the reasonable range of the three factors is determined according to the empirical formula, and three levels are selected for each factor. The orthogonal test method was used to select the best combination of 9 groups of test schemes, three field tests were carried out for each group, and the blasting effect was statistically and synthetically evaluated. The half-hole rate, the excess of underdigging and the depth of the residual hole were taken as the evaluation indexes. Based on the multi-objective grey situation decision theory, a reasonable smooth blasting scheme was obtained from 9 test schemes (50 cm spacing of peripheral holes, 60 cm thickness of smooth blasting layer, 0.27 kg / mg of line charge density). Finally, the ANSYS/LS-DYNA finite element software is used to simulate the scheme. The model of single row adjacent two peripheral hole steps is established and the propagation process of equal-effect force is analyzed. The equivalent stress magnitude of the specific element on the vertical line of adjacent two adjacent peripheral holes is analyzed. The scheme has been applied in engineering and achieved satisfactory blasting effect. According to the statistics of the quality inspection department, the average under-excavated amount is controlled at 6-10 cm, the maximum under-excavated amount is controlled within 15cm, the half-hole rate is about 75%, the utilization ratio of the gunhole is about 95%, the vault sinking and the horizontal convergence of the arch wall tend to be stable. This scheme can guarantee the engineering quality of Huanglianshan Tunnel and provide a safe construction environment for tunnel constructors.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U455.6

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