| With the development of social economy, the building industry is growing significantly and as a result, high, large, unique and novel buildings emerge like mushrooms. As is well known, buildings undergo deformations due to natural and man induced causes from the start of ground-breaking, and therefore, it is very important to find out deformation status, analyze causations, and predict deformation trends for preventing incidents and ensure the normal use. As there is a deeper knowledge of the importance of deformation monitoring, and with the implementation of relative laws and regulations, the deformation monitoring of buildings has been applied in engineering practices more and more widely, which makes the development of deformation monitoring system for large buildings more and more important. The dissertation is aimed at some hot and difficult issues in the deformation monitoring of large buildings, and the main work is as follows:1. The significance and status of the research of deformation monitoring of buildings were introduced. Study was made on the integral structure of monitoring system, software and hardware of such systems, the design of system communication as well as remote control methods. Special attention was given to the key part as well as the function of TPS data collector. The system communication and control system were illustrated in detail and their advantages as well as shortcomings and applicable environment were discussed.2. The origins, categorization and processing methods of surveying errors were analyzed. The sense of pre-processing of monitoring data to ensure data reliability was discussed from a general viewpoint.3. Systematic categorization and summing-up was made for current theory and methods of outliers processing. Analysis and comparisons were made on some commonly used outlier detection and some beneficial conclusions were drawn. Especially, a simple polynomial model was proposed for outlier detection based on correlation analysis method, and example shows that the method is easy to use and reliable in detection.4. Process Mutation Theory was applied for establishing the dynamic verification model of monitoring data, which is characterized by low computation workload and fast calculation. The model was proved effective in monitoring projects that involves a lot of points. In applications, the model combined with correlation analysis verification method can perform the identification of automated monitoring system for the authenticity of monitoring data and therefore improves the applicability of automated monitoring system. 5. Specific focus is put on the principle of Artificial Neural Network (ANN) and the method used in constructing monitoring model. For the problems with BP Neural Network, analysis was made and solutions were put forward to solve the problems. The dissertation proposed the method that applies nonlinear regularization function in the preprocessing of original data series and memorizing initial weight and valve values, which greatly improves the converging rate of BP model and prevents the model from reaching local minimum and thus raises the fitting accuracy of the model.6. The reasons why systematic errors are generated were analyzed. Several inspection methods of systematic errors were introduced. For the methods, their advantages and inapplicability situations were pointed out.7. For the systematic error hiding in polar coordinates measurement, a surveying scheme based on multi real time differencing method was presented, and theoretical analysis was made on the accuracy of the method, and furthermore, the Mean Square Error formulae in 3-dimensional coordinates were derived. The coefficients of the effect of Earth curvature and refraction were discussed in detail, which was proved to be chiefly determined by the coefficient of the vertical refraction of atmosphere.8. The GM(1,N) gray correlation model of the Gray System Theory was introduced. A method was proposed that improve model fitting using the degree of gray correlation in the selection of the independent variable of prominence, and a workflow of the solution of the improved gray correlation model was put forward.9. The gray correlation models for the refraction coefficients of observed directions were studied and set up, according to which the refraction coefficient for the observed direction can be solved readily, and real-time corrections can be made to the observed height difference, and thus the effects of refraction can be reduced effectively to a great extent. Therefore, the scheme of improved polar coordinates real-time surveying was presented for the first time. Field experiments demonstrated that the scheme can result in a better correction to errors of vertical refraction of atmosphere, and the application of the scheme was proved to be convenient. The scheme can effectively raise the precision of one-way trigonometric height surveying.10. Models of classic Kalman Filtering and the Extended Kalman Filter(EKF) as well as their solutions were introduced. The advantages and disadvantages and applicability of the two methods were also discussed in detail.11. The Sigma Point Kalman Filter(SPKF) method was introduced. Firstly the Sigma Point Transform was introduced and its accuracy was analyzed. Then the SPKF formulae were derived in detail. Examples showed the superiority of SPKF to EKF which are no need for the computation of Jacobi matrix, higher accuracy of prediction, more stable performance of filtering.12. Neural Network(NN) based SPKF was proposed for the first time and was applied in the modeling and prediction of nonlinear system of the deformation monitoring of buildings. The commonly used Back Propagation(BP) NN has some defects, like long training time, relying heavily on initial values and the proneness of reaching local extreme value although the NN has the basic advantage of approximating any continuous function and nonlinear mapping with high accuracy. However, the advantage of NN is embodied through the combination with SPKF. Experiment proved the applicability and effectiveness of NN based SPKF.13. Some representative monitoring projects that the author joined in recent years were introduced. A comprehensive analysis was made on the effect of the glass refraction of monitoring house which accommodates Total Station on the observed directions and observed distances, which can be used as reference for future monitoring projects. For large-scale buildings or extensive monitoring areas, the multi station real-time deformation monitoring system was constructed for the first time, and corresponding software and database systems were developed.14. For special monitoring situations like subway, the author joined in the construction of monitoring network system composed of multi stations. The creative method of real-time dynamic reciprocal traverse measurement was introduced, which filled the blank of domestic subway deformation monitoring field by solving the problems encountered in monitoring, such as blocked target, atmosphere torrent, ground base vibration, multi target interfering, etc. Filed applications demonstrated that the monitoring accuracy satisfied the demands of the project.
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