【作者】 王胜；

【导师】 黄润秋；

【作者基本信息】 成都理工大学 ， 地质工程， 2010， 博士

【摘要】 坝肩抗力体是维持拱坝稳定的关键部位,其稳定性是拱坝建设中的关键工程地质问题之一,坝肩地质缺陷的存在可引起岩体的承载力不足、抗变形能力差,从而导致坝体的变形甚至失效,直接威胁水电站的正常运营。因此,在对坝肩抗力体地质缺陷研究的基础上,建立一套加固处理技术方法体系,对水电站工程建设具有较强的指导意义。本文以锦屏一级水电站左岸抗力体为工程背景,从工程地质条件着手,紧扣岩体结构特征,进行地质缺陷工程地质研究;根据地质缺陷对拱坝和坝肩稳定的影响分析,确定缺陷体的加固处理措施,针对主要的加固措施(缺陷体网格置换和缺陷体固结灌浆)进行专门的技术研究,所获得的研究成果应用于现场实际工程,并就存在的问题和不足进行优化和完善。以理论为基础,以工程应用为目的,构成了复杂地质条件下高拱坝坝肩(基)地质缺陷(体)及加固处理技术研究比较完整的理论与实践体系。主要研究成果体现在以下几个方面:(1)在把握研究区工程地质条件基础上,结合结构面成因、结构面工程地质分级、结构面的现场调查,将锦屏一级左岸抗力体主要发育的结构面概化为断层、层间挤压错动带和基体裂隙三类,对其进行工程地质分析,获得了各类结构面的空间分布规律及物质组成特征。对左岸抗力体岩体结构划分为厚层～块状结构、中厚层状～次块状结构、次块～镶嵌结构、块裂～碎裂结构、板裂～碎裂结构和碎裂～散体结构六种类型。(2)在拱坝基础地质缺陷理论分析基础上,根据左岸抗力体前期勘探及施工期5层基础处理洞室开挖揭示的工程地质条件,结合坝基岩体质量分级标准,先进行野外岩体质量初步分级,再结合钻孔声波、孔内变形模量、RMR分类统计等手段,综合岩性、地质构造、岩体结构、嵌合紧密程度及风化卸荷、深部裂缝的发育程度等地质特征,对左岸抗力体岩体质量进行综合评价,获得了各级岩体的工程地质特征及其空间展布规律。(3)在岩体质量综合评价基础上,对左岸抗力体地质缺陷划分为断层破碎带、层间挤压错动带、煌斑岩脉、深部裂缝、Ⅳ2级岩体、Ⅲ2级岩体等六种基本类型进行详细的工程地质特征分析,获得了各类地质缺陷的空间分布规律、物质组成、物理力学特征等。(4)分别对地震层析成像技术和智能钻孔全景图像技术在左岸抗力体地质缺陷评价中的应用进行了分析。分析结果表明,地震层析成像和智能钻孔全景图像结果与现场的岩体质量具有较好的对应关系,地质缺陷在地震层析成像和智能钻孔全景图像结果中得到了较好的体现。(5)在缺陷体网格置换技术研究中,从置换网格开挖、支护、衬砌、灌浆与混凝土回填等方面进行了较为系统的分析研究。鉴于置换网格特别复杂的地质条件及施工技术特点,确定了置换洞开挖“预灌浆、短进尺、弱爆破、强支护、勤监测”,斜井开挖“先超前灌浆、后导井开挖、再边扩边衬、全过程监测”开挖支护原则。安全监测结果表明所采取的工程措施行之有效。从而构成了以锦屏一级左岸抗力体f5(f8)断层、煌斑岩脉为工程背景的网格置换技术比较完整的技术体系。(6)按灌浆技术特点、灌浆材料、灌浆方法的差异对抗力体固结灌浆进行了分区。然后分主灌浆区、控制灌浆区灌浆,深部裂缝灌浆和f5断层、煌斑岩脉灌浆三部分对其进行了较为系统的研究,构成了针对左岸抗力体地质缺陷固结灌浆比较完整的技术研究体系,为不同类型地质缺陷的固结灌浆处理提供了可行的方案,并对其它复杂地质条件下坝肩(基)的灌浆加固处理具有借鉴意义。(7)对P.O.42.5、P.O.52.5普通硅酸盐水泥浆液性能进行了试验研究,采用复合外加剂同时对水泥浆液凝结时间和早期强度进行改性,分别对LLS+FDN和CaCl2+SGJ-1两种复合外加剂方案进行了试验分析。在此基础上进行了湿磨细水泥浆液和稳定浆液的试验研究。(8)针对主、控制灌浆区的工程地质特征,对“孔口封闭、孔内循环、分序加密、自上而下”高压固结灌浆在其中的应用进行了分析研究。对典型的Ⅳ2级岩体现场灌浆试验进行了分析。针对灌浆质量检查中存在的一些问题从灌浆材料、灌浆参数、灌浆方法及灌浆效果检查等方面进行了优化建议。(9)针对左岸抗力体深部裂缝灌浆技术特点开展了水泥-水玻璃控制性灌浆技术研究。从胶凝时间和强度变化规律对水泥-水玻璃浆液进行了试验分析,对初凝时间为5min的水泥-水玻璃浆液进行了配方设计;针对深部裂缝及水泥-水玻璃浆液的特点,提出对深部裂缝采取“双液孔口混合式”水泥-水玻璃灌浆方法,采用“自上而下、孔口封闭、纯压式”施工工艺。(10)针对f5断层、煌斑岩脉灌浆技术特点开展了水泥-化学复合灌浆技术研究。在水泥-化学复合灌浆机理分析基础上,确定了灌浆处理程序和总体方案,对水泥-化学灌浆材料、灌浆方法进行了分析。对f5断层和煌斑岩脉水泥-化学复合灌浆现场试验进行分析研究。根据灌浆质量检查结果,从灌浆材料、灌浆参数和灌浆效果检查等方面提出了优化建议。更多还原

【Abstract】 Dam abutment resisting force body is key parts to maintain stability of arch dam and its stability is one of the important engineering geology factors in the process of arch dam construction. What’s more, the dam will failure triggered by deformation and constitutes a direct threat to normal operation of hydropower stations induced by the geological defects of abutment will result in the carrying capacity lacking and weak deformation resistance.Therefore, it has a quite strong practice indirection meaning to establish a reinforcement treatment system based on geological defects of dam abutment resisting force body.This paper conducts a research on the geological defects and reinforcement of the high arch dam abutment(base) with complicated geological condition, on the basis of the resistances on the left bank of the Jinping ? Hydropower. under the guidance of the geological defect basic theory and the weak rock masses reinforcement theory. To start with, this paper carries out a research on the engineering geological conditions of the geological defects by combining with the structure characteristics of the rocks. Afterwards, the reinforcements of the defects have been confirmed according to the analysis of the geological defects on the stability of the arch dam and dam abutment. Finally, the specific technological research has been made according to the main reinforcement, namely, defects displace and consolidation grouting, the achievements of which will be applied to the field engineer and the limitations improved. On the basis of the theory, the paper has constructed a relatively complete system of theory and practice of the geological defects and reinforcements of the high arch dam abutment(base) with the complicated geological conditions with the aim of the engineer application. The main achievements are as follows.(1)After obtaining the engineer geological condition in the study area in combination with the cause, the geological classification and field investigation of the structure surface, the main developed structure surface of the resistance on the left bank of Jinping ? Hydropower can be summarized as three kinds, namely, faultage, disturbed belt as a result of layer squeezing and the matrix crevice. After analyzing the above three kinds of structure from engineer geological perspective, the rule of space distribution and characteristics of physical makeup have been acquired. There are six kinds of structures about the resistant rocks on the left bank, which are in the form of thickness to massive, medium to sub-massive, sub-massive to mosaic, taphrogeny to splintering, board split to splintering, splintering to dispersion.(2)On the basis of the analysis of the geological defects of the dam base, firstly, we tentatively make the classification of quality of the rock mass in the field in combination with the classification criterion according to the engineering geological condition disclosed during exploration in the earlier stage and the excavation of the five-storeyed grotto under the construction. The comprehensive assessment of the rock quality of the resistance on the left bank have been made when combining the geological characteristics including synthetical lithology, geological structure, structure of rock mass, inosculating-intensity, unloading, development of the deep crevice by means of the drill hole sound wave test, hole deformation modulus, and RMR classification statistic. Finally, the engineering geological characteristics of the rock mass in all levels and space distribution rule have been acquired.(3)On the basis of the comprehensive assessment of the rock quality, we have classified the resistant on the left bank into six basic types, namely, faultage splintering belt, disturbed belt as a result of layer squeezing, lamprophyric dyke rocks, deep crack,Ⅳ2 rock mass,Ⅲ2 rock mass, and carried on the detailed analysis of the engineering geological characteristics. In the end, we’ve obtained the rule of space distribution, physical makeup, and physic mechanics of all kinds of geological defects.(4)After combining the engineering geological characteristics of the defects on the resistant of the left bank, we’ve made the analysis on the seismic tomography image formation technology and the application of intelligent drilling panoramic picture in the geological defects. The analysis shows that seismic tomography image formation and intelligent drilling panoramic picture correspond well to the rock quality in the field and the geological defects can be best manifested in those pictures.(5)We’ve made a relatively systemic analysis and research on the excavation, supporting, lining, grouting, cement concrete backfilling .Due to the replacement grid of the complicated geological conditions and the special features of construction technology, excavation supporting principle are : Replacement hole excavation of Pre-grouting, short footage, weak blasting, strong support and frequent monitoring. Slope wells excavation of First Pre-grouting, advance guide wells excavation, again lead Wells edge extension lining and all-process monitoring. It’s so effective from the safety monitoring results to show the engineering measures that a relative complete technical system is constituted, which is from the grid replacement technology of fault f5 (f8 ) and lamprophyre dike on left bank resisting rock of Jinping I Hydropower. The research results can be Referenced to similar projects.( 6 ) A classification is made accoding to the difference of Technical characteristics ,materials ,and methods of grouting. And make a systematic research in the aspects of main-grouting area、grouting-control area grouting , the deep crack grouting area,f5 fault、Lamprophyric dike grouting area. a comparative complete technical architecture object to the consolidation grouting of the geological defects resistence of the left bank. Thus, it provides available plans for the consolidation grouting trentment in various kinds of geological defect and have a great consultant significance for the treatment of fracturing grouting for foundation soil dam abutment (base) in other complicated geological conditions.(7)A test was made for the property of the Portland cement grout 425#、525# to get it’s performance index and an analysis of it’s setting time and the variations rule were also made. Compound admixtures was adopted to change the setting time and initial strength at the same time ,and make experiment and analysis on the LLS+FDN and CaCl2+SGJ-1 plans separately. Portland cement grout 525# was adopted as the main materal for the experiment and research of wet cement grout and stable grout.(8)According to the engineering geological characteristics of main grouting area and control grouting area where the principle is orifice closed ,cycle hole, encryption and top-down sequence, high pressure consolidation grouting in one of the application is analyzed. ChooseⅣ2 rock mass ,which controlled by the typical fault and deep crack, to do a grouting test. Some problems exists in the process of grouting quality inspection. The optimize recommendations is given from grouting materials, grouting parameter, grouting method and grouting effect.(9)For the feature grouting in deep cracks of left bank resistance rock, technology research about the cement - silicate controlling grouting is conducted. Cement-silicate slurry experimental analysis is consistsed of setting time and strength variation. Got the formula design for early in the coagulation time for 5min cement-silicate slurry. In features of deep cracks and cement-silicate slurry, came up with dual fluid orifice hybrid cement-silicate slurry in deep cracks. Construction process is Top-down, orifice and pure pressure.(10)According to the faults f5 and lamprophyre dike grouting technique characteristics, technology research about the cement- chemical compound grouting is conducted. On the basis of the mechanism for cement-chemical compound grouting, determined the grouting process and the overall scheme. Cement grout is for top-down, orifice closed, circulating, section grouting. Chemical grouting is for orifice closed and pure pressure.On this basis of it, the cement - chemical compound grouting field test about faults f5 and lamprophyre veins was hold to check the quality so as putting forward optimize Suggestions on grouting materials, grouting parameter and grouting effect check.更多还原