| Grouting is an engineering treatment technique with strong practicality and wide application range. At present, all grouting theories, grouting technology and grouting effect inspection means are lack of being systematically studied and they have not formed a perfect method system and technical regulation in the Chinese highway tunnel construction. Thus there are a certain blindness and unreliability for the design, construction quality control and grouting effect assessment. Therefore, taking the shallow-buried section of Tongluoshan tunnel of Dianlin highway in the karst area and the tunnel serious water leakage section as research objects, based on the field grouting test, this paper made a thorough, systematic study on quality inspection methods , assessment criteria and grouting effect evaluation system of before and after grouting and initially established quality inspection methods, assessment criteria and grouting effect evaluation system suitable for highway tunnel grouting technique in karst area. On the basis of the above-mentioned results, combined with hydraulic and hydroelectric grouting design technique, the author compiled a grouting technique guideline for highway tunnel in karst aera to provide preference for the design and construction of similar projects in future. The specific research contents and main results acquired are as follows:1. According to the features of all kinds of inspection means before and after surface grouting of Tongluoshan tunnel and related result analysis, aiming at such characteristics of surface grouting as large scale, great uncertainty, little influence on construction procedure and easy to seal hole, it was determined that the sonic wave testing in borehole and visual core observations were main means and water pressure test, rock sample lapping identification detection were supplementary for the surface reinforcement grouting quality inspection in karst area.2.According to the features of all kinds of inspection means before and after tunnel grouting of Tongluoshan tunnel and related result analysis, combined with such characteristics of the tunnel grouting as small depth, long bid section, great influence on construction procedure and easy to cause damage to initial linings, it was determined that geological radar detection, the cement injection rate analysis were main means and geologic three-dimensional CT test, water pressure test were supplementary for the bakfill grouting quality inspection in karst area.3. By means of the comparison between the results acquired by all kinds of inspection means of tunnel grouting and tunnel excavated filed, combined with hydraulic and hydroelectric detection criteria, the assessment standard system of surface reinforcement grouting and bakfill grouting of tunnels in karst area was established.4. Utilizing the system reliability theory to make an analysis of grouting quality reliability index of two kinds which were respectively surface reinforcement grouting and bakfill grouting, and calculating their system reliability probability, the calculation results were basically identical with tunnel practical excavated results, which could well reflect reality result of grouting.5. Based on tunnel grouting theory, quality assessment index of surface reinforcement grouting and backfill grouting was established. Each of them contained such 5 aspects as grouting carrier integrity, continuity, sturdiness, termination condition, reliability probability. The comprehensive quality assessment of surface grouting and bakfill grouting in Tongluoshan tunnel was made by utilizing hierarchy -fuzzy theory comprehensive evaluation to implement and the results showed that the quality of surface grouting was the best and that of bakfill grouting was relatively good.6. Integrating the research results of grouting test design, indoor grout formula experiment, site grouting test, quality detection before and after grouting and grouting effect assessment system, based on consulting lots of related literatures on grouting design, construction, detection, the author preliminarily compiled a grouting technique guideline for highway tunnel in karst area to provide preference for grouting projects of which the engineering conditions are similar.
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