| Rely on the double-arch tunnel project at Yumujianggou, the study on tunnel convergence, tunnel surrounding rock displacement, sound wave test for surrounding rock, surrounding rock pressure test were carried out to monitoring and analysis on the bearing capacity and deformation behaviors of tunnel surrounding rock during the tunnel construction process.Using surrounding rock classification, monitoring measurement, finite element numerical simulation to evaluate the stability of tunnel surrounding rock.During the evaluate stability of tunnel surrounding rock., geomechanics model can well showed the mechanism and process of deformation and failure of tunnel surrounding rock., especially when the the rock structure was complicated, such as when the structural plane has effect by weak intercalation and fault.Using the bottom friction simulating test which is a test concluded in geomechanics model to simulated the characteristic analysis of defomation and failure during tunnel excavation, study the mechanism and procedure of tunnel destruction considering the different rock mass structure type and mecanical medium of rock mass,and study the interaction mechanism between support and surrounding rock.Because of the importance of the stability evaluation and support to the tunnel surrounding rock, many scholars have put a lot of energy in the research of echnical properties of rockbolts, finite element analysis on double-arch tunnel excavation project, geological advanced prediction method in tunnel excavation, reverse calculation algorithms method in tunnel excavation, composite lining of supporting pressure, shotcrete technique, optimal shape of tunnel excavation, flexible advanced support.But nowaday, the tunnel analysis also have some deficient aspects, such as in forecast of the engineering geological condition,analysis stability of surrounding rock, information mornitoring system, surrounding rock support, construction quality inspectied system and comprehensive analysis software. According to the current research status of tunnel engineering, the methods of prediction, evaluation, monitoring and support design system has been researched systematically. With this research, system software development in support decision of road tunnel has been made, and it includes forecast system for engineering geological conditions of road tunnel, surrounding rock classification and bolt-shotcrete support design system of road tunnel, analysis system for stress-strain and rock pressure of road tunnel, information monitoring system of road tunnel, detection system for spray anchor quality of road tunnel. It is a variety of norms on the basis of the actual works as a carrier to serve the practical engineering, you can make quantitative evaluation of the stability of the surrounding rock for the tunnel rapidly and accurately with it.(1) Forecast system for engineering geological conditions of road tunnel Engineering geological environment of the tunnel surrounding rock is an important basis to the evaluation of the stability of the surrounding rock and support. At the time of the tunnel excavation to predict engineering geological environment such as the fault, fracture zone, groundwater, high ground stress accurately is very important work to ensure the stability and security of the tunnel during the construction process.The forecast system for engineering geological conditions of road tunnel has been developed to solve this problem. The main function of this prediction software includes the forecast of engineering geology environment such as the broken and weak structure forecasting, the ground stress forecasting, water gushing prediction. The system not only can forecast a single content, but also can forecast it in several methods at the same time or repeat, and it can forecast with a comprehensive system, which can obtain the most accurate prediction of the outcome if the conditions are allowed.(2) Surrounding rock classification of Highway tunnel and shotcrete rockbolt support design systemRock is a very complex geological body. There are various types of objective existence. The essence of surrounding rock classification is to correctly understand and reflect the objective existence by abstraction generalization and simplification of the different rock .Together with experience in the excavation of rock in underground engineering .Building a bridge to guide design and construction of geotechnical engineering .These have become the stability evaluation of surrounding rock and the main basis for the support design.The development of surrounding rock classification of Highway tunnel program is mainly accordance with the existing "design specification of highway tunnel" and "standards of engineering rock classification." These classification standards should not be fixed, in order to be able to properly use the experience of other Highway tunnels or design, and therefore also introduction of dynamic classification system and system cluster to analyze the data of the existing tunnel design and grading. In accordance with their classification inherently act in the law to reduce man-made subjective factors. In order to adapt to the needs of today's information highway tunnel construction, a software system has been developed in order to achieve fast and accurate surrounding rock classification and guide highway tunnel construction.In addition, on the basis of the surrounding rock classification and basis to normalize the system can carry out bolt shotcrete support design and determine support types and design parameters. It also contains the development of local bolt shotcrete support design systems which base on a large number of bottom friction test and the supporting scheme which proposed for more than 150 kinds of combinations form. It can clear the different formation dip, the number of weak structural plane, the combination of angle and direction of the local bolt shotcrete support design form. In the theory, it has achieved a high level of analysis to determine the local anchor of the reinforcement design. The system has the characteristics of user-friendly, targeted and data processing feedback fast. It can timely determine the reinforcement design, as well as to the support from.(3)Analysis system of stress and strain and pressure of surrounding rock in highway tunnelsThe so-called stability of surrounding rock is a relative concept, which studies the relative relationship between the redistributed stress and strength of surrounding rock.In general, when the stress of one point in surrounding rock achieves the corresponding strength of surrounding rock,surrounding rock is considered to be destroyed.Otherwise,it is undestroyed.That is to say,surrounding rock is stable.Therefore,the stability analysis of surrounding rock in underground caverns includes two steps.First, determine the size and characteristic of the redistributed stress after excavation according to the natural stress state of rock mass where the project is based on.Second,study the contrast relationship between the stress and deformation and the strength of surrounding rock.Then evaluate the stability,as the basis of the design and construction of highway tunnels.The system analysising stress and strain of highway tunnels includes the following methods:FEM, BEM, classic surrounding rock pressure theory and the relevant provisions of the design specification of highway tunnels.(4) information-based monitoring system of highway tunnelsMonitoring is the main content of new austrian method.It is not only the important measure ensuring the quality of projects,but also the main way to determine the stability of surrounding rock and lining,guarantee the safety of construction,guide the order of construction, manage construction and provide design information.In view of the importance of monitoring, we have developed the monitoring system of tunnel surrounding rock.The system mainly includes inputting and storing all types of onsite monitoring data,drawing graphs,regression analysis,calling and modifying the primary pre-design program,dynamic feedback of monitoring information and optimization of the initial support.The system having fast calculation speed and drawing ability can process the monitoring information simultaneously and really solve the problem like the huge amount of monitoring data which is difficult to deal with. In the tunnel Construction,applicating the system can not only obtain accurate and effective information,but also can be used as an active and effective measure of construction management, in order to grasp the dynamic state of surrounding rock,forecast the development trend of the tunnel stability accurately, revise and control the design parameters and construction process,ensure the tunnel project safe and smooth and make sure that the tunnel project has good economy.(5) highway tunnel spray anchor quality detection system There are quality detections of sprayed concrete and bolt according to criterion strictlyspray in anchor quality detection system. Including the detection of the compressive strength of shotcrete, the detection of the thickness of the shotcrete, as well as quality detection of anchor and so on. Spray anchor supporting quality detection during the construction phase will assure the quality of front process on the one hand and new process is beginning. Another Feedback has played a role in the adoption of quality assessment, you can accumulate a large number of quality information on a regular basis to analyze this information, research, and reasonable measures to improve the quality, we can make the quality of the project under control, which played a prevention construction Arising in the course of quality problems.In practice, using this system, you can quickly and accurately detect the quality .It will helpful for keeping out quality problems and creating normal conditions in the construction, to ensure the safety of the tunnel project and the successful construction. At the same time, avoid Disputes arising in the construction as a result of quality problems and delaying acceptance of the tunnel project and the use of the issue, which has had a major indirect economic and social benefits.The main innovative points:1.The use of a physical simulation to determine the typical pattern of damage to the surrounding rock cavern and the map of a typical rock bolting way is proposed in order to providing the decision-making in the dynamic design and construction.2.Develope a complete system, complete function fast access to the tunnel construction, rock mechanics information on changes in the status of monitoring, testing and prediction of the highway tunnel decision support system software.3.The establishment of dynamic clustering of rock classification with multi-parameter and multi-method enrich the highway tunnel surrounding rock classification system.
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