| 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,â…£2 rock mass,â…¢2 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. Chooseâ…£2 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.
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