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Performing genomic large segmentation experiments will promote the annotation of complex genomic functions and contribute to the synthesis of designed genomes. It is challenging to obtain and manipulate large or complex DNA sequences with high efficiency.This study aims to develop an effective method for direct cloning of target genome sequences from different species.The TelN/tos system and a linear plasmid vector were first used to directly clone the large genomic segments in E. coli. For the in vitro cloning reaction, two telomeric sites were developed using TelN protelomerase at the end of the linear plasmid vector. The target DNA sequence can be easily hooked with the homology arms and maintained as a linear artificial chromosome with arbitrary restriction sites in a specific E. coli strain.Using the linear cloning strategy, we successfully cloned the bacterial DNA fragment of 156 kb, a yeast genomic fragment of 124 kb and mammalian mitochondrial fragment of 16 kb. The results showed a considerable improvement in cloning efficiency and demonstrated the important role of vector ratio in the cloning process.Due to the high efficiency and stability, TAPE is an effective technique for DNA cloning and fundamental molecular biotechnology method in synthetic biology.

Extra long span rail transit bridges are generally slender and sensitive to excitations, and alignment control of the bridges should be conducted during construction. In this paper, the self-adaptive Kalman Filter (SKF) method was applied to the alignment control of the second longest rail transit bridge in the world. Each influential factor of the bridge alignment was firstly introduced. Then, the finite-element analysis and field tests of the bridge were carried out to obtain the influential factors that induced bridge cambers quantitatively. Combining with the cambers, the SKF method was applied to the alignment control of the bridge. Comparisons of the SFK-predicted alignment with the target alignment or the field measured alignment were carried out. Results show the SKF for alignment control of bridges is feasible and reliable.

Considering that the health monitoring system and construction monitoring system are not combined flexibly, the whole life monitoring model is conceived. That method is based on data dependence analysis of pre-buried and table-posted sensor, at the same time, correction of monitoring data is also taken into consideration. All the works focus on the research about collaborative work mode of monitoring data from pre-buried and table-posted sensor. This achievement brings so many benefits, firstly, it makes dead loads and living loads are considered together. Secondly, it brings new ideas to guarantee the safety of large bridges in construction or operation. Thirdly, the research results are embodied fully in the engineering practice of Nujiang Bridge.

This paper puts the internal force envelope method in bridge design into the safety assessment of bridges’ health monitoring, and proposes a safety assessment technology based on the method, which is stated in three aspects: the safety assessment modal, the acquirement of the real-time Figure of bridges’ internal force resistance and of the real-time Figure of bridges’ internal force. After the application in the Nu Jiang Bridge, it is proved that the safety assessment technology based on the internal force envelope method is simple, easy to understand, reliable, visualized and prospective in further application.

Based on the analysis of chaotic time sequence and the characterization to the system chaotic property from it’s characteristic index, we established finite element model about ASCE Benchmark. Then we got 4 acceleration time sequence of Benchmark model by simulation of instantaneous excitation. At last, we made a experimental analysis on the maximum Lyapunov exponent. As the result shows, all maximum Lyapunov exponents are above zero. It means that chaotic phenomenon appears in the structure system. At the same time, maximum Lyapunov exponent shows it’s sensitivity along with the evolution of structural condition. That is to say, the statement of structure could be reflected by the chaotic index of chaotic time sequence. Then we get new ideas on the study of safety assessment relied on the structural health monitoring.

In this paper, ASCE Benchmark Finite Element Model was established and analyzed. Also, The MLI(the max Lyapunov Index) and LISE(Lyapunov Index Spectrum Entropy) has made to recognize state of the FEM using non-linear theory and chaos time sequence. The results show that MLI and LISE are sensitive with the structure state, and the structure system is chaotic.

This paper shows the stability of cable-stayed bridge under floating system. A large-span prestressed concrete cable-stayed bridge in Chongqing is analyzed by using nonlinear finite element program ANSYS. The buckling mode and linear and nonlinear stability safety factor of the bridge under two unfavourable live loads are gained and compared by numerical simulations. The results show: 1) only in-plane instability is induced regardless of the loads；2) Under the floating structure system, nonlinear stability safety factors of the bridge under two unfavourable live loads do not meet the specification requirement four, but they are actually bearing capacity stability factors, and should be said adequate safe when they can reach about three. Limit value on nonlinear stability safety factor of the bridge does not provide at present, but we believe that in general about three should be able to meet the requirement through the practice of some of the previous bridge

Based on damage mechanics and thermo, the mechanical degradation of concrete material under the coupled action of stress and freeze-thaw cycles was analyzed in this paper. The tensile stress in concrete during freeze-thaw cycles was obtained considering freezing-induced pore pressure variation with the change of temperature. A revised fatigue fracture model is proposed for the reliability analysis of concrete durability, which can evaluate damage status and the remaining service life of concrete structure after freeze-thaw cycles with different loading levels. The present model can serve as references for design and safety assessment for concrete structures in cold regions.

In this paper, the performance of concrete is studied through different water-cement ratio, different air-content, different mineral admixtures, different admixture contents, examined the mechanical properties of concrete, electric flux and chloride ion penetration depth of different mix concrete. The results show that, decreasing w/c ratio, proper air content, adding mineral admixtures can improve the resistance of chloride-permeation. Within some contents, the chloride-permeation resistance using silicides is better than that of fly-ash or slag. On this basis, the proper scheme of mix ratio used in saline area is recommended: the air-content is 3%～5%, the content of fly-ash or slag is 20%～30%, the content of silicides is 6%～8%, and double mixed with silicides.

The paper has made a maximum Lyapunov exponent and Lyapunov exponent spectrum entropy analysis of ASCE Benchmark using non-linear theory and chaos time sequence. The maximum Lyapunov exponents in the two kinds of structural monitored data are both over zero, indicating that in the structural system chaos phenomenon has appeared. And, experiments have shown that the maximum Lyapunov exponent is sensitive of the amount of samples and the time delay. So, to compute the chaos index, the amount of samples and the time duration are of importance. Meanwhile, the Lyapunov exponent spectrum entropy is effective to measure the chaotic characteristic of the system, but ,the entropy is less sensitive to state recognition more than the max Lyapunov exponent.

This paper presents an analysis of the nonlinear characteristics of a bridge structure and the chaos of BHM(bridge health monitoring) information. Chongqing Masangxi bridge’s BHM information is analyzed by using the max Lyapunov index with Wolf and correlation dimension with G_P algorithm. The results show:1) all of the max Lyapunov index is nonnegative ;2)the correlation dimension is non-integeral and greater than 2.These proves that the bridge structure is in the chaos. Meanwhile, with the evolution of time, the index of chaos is sensitive with status of structure system and varies in different key sections of bridge structure. These findings lay a solid foundation for the further development of bridge safety assessment and prediction when non-linear chaotic theory is utilized to analyze the bridge health monitoring information.

BHM is an important means to assess and predict the safety operation of large bridge in service around the world. Given the missing of real-time monitoring information for some time and the lack of effective theory and technique to capture the missing information and even to predict the evolution of structure, this paper made an attempt to predict the evolution of monitoring information using time series and chaotic theory. Firstly, maximum Lyapunov exponent of available monitoring information is calculated to assess the chaos of the bridge structure. The parameters of reconstructed phase space, correlation dimension and time delay, are calculated by C-C algorithm and G-P algorithm respectively. According to empirical formula, one 3-layer BP neural network is established Ten recursions are carried out. The results show that multi-layer recursive BP neural network is able to predict BHM information. Using chaotic time series to reconstruct phase space and applying multi-layer recursive BP neural network to predict BHM information facilitates further estimation and prediction of bridge safety condition by means of chaotic nonlinear characteristics.

Set out from a basic idea that damage is a course of energy dissipation, a new damage variable is present. The damage variable is obtained for arbitrary strain state of soil according to the superimposing principle of compatible probability event for volumetric strain and shear strain. Through the analysis of a series of triaxial experimental results of structured soil, a new damage evaluation equation is put forward. The computation results tally with the experimental data show it is reasonable that this new damage variable and its evaluation law for structured soil.

A constitutive model for isotropic damage of geomaterial is put forward, and its numerical computation procedure is given also. The calculated results for a simple example could highlight our understanding about the mechanism of geomaterial damage, and several useful conclusions can be drawn: The series assumption can not be used to synthesis mode of stress and strain for complexus theory of geomaterials damage; strictly speaking, the parallel assumption can not be used to that of geomaterials damage also; the complexus stress-strain behavior like that of ideal natural geomaterial under small stress, and like that of reconstituted soil under large stress.

How to simulate stone arch bridges with moving vehicles is an important problem in numerical simulation research. How to obtain the characteristics of stress and displacement under the moving load is urgent task for bridge construction. Taking a stone arch bridge with 60m span length as an example, in this paper, a three dimensional model for the stone arch bridge is created and the bridge under the traveling load is numerically simulated, based on a modified ANSYS software package. The distribution law of the stress and displacement of the stone arch bridge at different time is analyzed. The change rule of the stress and displacement during vehicles pass through the stone arch bridge is discussed. The numerical simulation results in this paper provide a foundation for the fatigue life-span analysis of stone arch bridges. The technology of coupling vehicle and bridge provides a new way for numerical simulation studies.