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This paper based on the unified strength theory, analyzed the ultimate bearing capacity of the reinforced concrete columns combined with FRP under axial loads. First, analyzed the mechanical property of the RC columns combined with FRP. Second, based on the unified strength theory, deduced the three-direction compressive stress of the core concrete and got the unified formula for calculating the ultimate bearing capacity of RC columns combined with FRP. Last, compared the analytical results obtained in this paper with the relevant experimental data, good agreement can be found and it proved the good applicability of the formula. Comparing with other methods in calculating the ultimate bearing capacity of RC columns combined with FRP，this method is well-founded, so it has a significant value in analysis of RC columns combined with FRP.

Under external loads, the continuously prefabricated slab of double-block ballastless track may crack easily. The cracks will reduce the durability and carrying capacity of the roadbed slab. Moreover, the cracks may also affect the use and safety of the double-block ballastless track during its service. When the roadbed slab crack, we should take some maintenance measures to maintain the normal use and durability of the double-block ballastless track. This paper based on the finite element method, established a beam-brick model for double-block ballastless track which has a through crack on the roadbed slab to analysis what kind of patching material is the most suitable when the most unfavorable loads act on the track. For this reason, we can provide theoretical basis for maintenance of double-block ballastless track .

Infill walls,etc. non-load-bearing walls are vulnerable to fracture when these are subjected to out-of-plane seismic loads. Studies suggest that the overall dimensions of non-load-bearing walls are the important parameters to affect its out-of-plane mechanical properties, but most of these researches are qualitative researches, do not give specific size limitations. This paper based on codes has calculated out-of-plane loads of non-load-bearing walls, then bearing capacity check formulas have been deduced when non-load-bearing walls are subjected to out-of-plane seismic loads, finally the size limitations used in the height-thickness ratio check and seismic check are obtained.The conclusions fill up gaps in research of non-load-bearing walls ,and provide reference for the design specifications of non-load-bearing walls.

Many masonry domes in their lower portion are subjected to hoop tensile forces which mostly lead to vertical cracks appearing along the dome's meridian planes. A close inspection of any such dome reveals these hoop tension cracks. The dome stands as a series of arches with common key stone, with cracks as a matter of non-structural consequences. Different strategies have been considered historically to arrest these cracks. The provision of tension ring mechanism adds to the stability of these domes, and hence many masonry domes are retrofitted with the provision of the tension rings using steel and FRP rings. The challenge in such retrofitting will remain to analyze its effect on stability of these masonry domes, more specifically in absence of reliable mechanical properties of such masonry domes. This paper presents a simplified analysis procedure combining thrust line analysis with the finite element analysis called here as Finite Element Thrust Line Analysis (FETLA). The development of a new element suitable for masonry dome analysis to include the effect of hoop tension cracks is demonstrated. The orthotropic material properties are utilized for penalty approach to allow redistribution of the forces from meridian direction to the hooping rings, with thrust line approaching the extrados or intrados of the dome. The analysis results of FETLA are validated with the previously available results. The analysis method proposed in this paper gives the rational estimates for the failure load without utilizing inelastic properties of the material to model the hoop tension cracks and its propagation.

The paper analyses the effect of Soil-Structure-Interaction (SSI) on the modal dynamic response of simply-supported span girder bridge with wall piers founded on caissons. A parametric analysis has been carried out in the hypothesis of linear elastic behaviour of all materials (soil and structure) to identify the influence of various design factors, such as the height of the pier, the caisson embedment below the ground level and the soil mechanical properties. The goal of the paper is to highlight SSI effects on the dynamic behaviour of bridges. This is a crucial aspect to be accounted for in order to support monitoring activities on bridges, aimed to structural identification or assessment of structure response under serviceability conditions, or also to have preliminary information for the seismic analysis of the bridge.

Integral Abutment Bridges are widely utilized around the world because they offer a design alternative minimizing the potential construction and maintenance difficulties associated with expansion joints in other types of bridges. However, integral bridge systems also have certain issues that result from the absence of expansion joints. This is because temperature changes induce cycles of elongations and shortenings in the bridge deck which lead to rotational movements in bridge abutments against and away from the retained soil. This phenomenon may develop long term problems in terms of settlement of the backfill at the bridge approach and escalation in the lateral earth pressure acting on the bridge abutments. This paper aims to investigate the approach settlement and lateral earth pressure development in integral bridges abutments using finite element modelling of a concrete bridge abutment and the adjoining soil using the ABAQUS software. The paper presents a parametric study of the effects imposed by abutment movements on the retained soil. This study also investigates the effectiveness of using expanded polystyrene (EPS) geofoam inclusions as a remedial measure to minimize the approach settlement and lateral stress ratcheting effects in Integral Abutment Bridges.

This paper deals with a problem of earthquake of the cylindrical tank. During the seismic event, the load acts in one direction only, i.e. in the direction of earthquake. This load imposes a non-symmetrical loading of a structure. At seismic load of structure of cylindrical tank was used accelerogram. In final part of the paper some crucial results are presented both in a graphical and numerical way.

Now the most pressing and to end unresolved question is the determination of the design parameters for the base in the conditions of formation of karst deformations. Foundation calculations made on the basis of forecasting karst manifestations sizes and the likelihood of their formation at the base of the designed construction. In paper presented the grillage calculation scheme. We calculated the grillage with four bays for four cases: excluding karst collapse, taking into account the collapse of a single support, taking into account the collapse under two not adjacent supports and taking into account the collapse at two adjacent supports. In paper presents the diagrams of bending moments and shear forces.

This paper will present testing of masonry walls made from clay block and concrete block. Experimental testing of the walls is done in the laboratory of the University of Civil Engineering in Podgorica within the national scientific research project "Seismic risk reduction in buildings of stone and brick". This paper presents the results of testing samples of walls built with the tested masonry elements and mortar. Characteristic compressive strength of the walls and elasticity modules were obtained. An analytical approach to determining the characteristic compressive strength and elasticity modules of masonry walls is analyzed in accordance with the applicable standard of Yugoslavia PIOVS'91, European standards EN 1996-1-1: 2005 and the American standard ACI 530.

Masonry is a complex multicomponent composite consisting of dissimilar materials (brick / stone and mortar). Masonry deformation process under loading depends on the mechanical characteristics of the basic composite materials, as well as of the parameters of the elements defining binding between brick and mortar being the interface elements. Traditional methods of masonry modeling are based on the use of generalized ("effective") mechanical properties of the composite as a continuant homogeneous continuant medium. This paper presents an overview and analysis of continuant masonry models adequately reflecting the process of elastic, and in some cases elastic-plastic masonry deformation within the composition of stone structural elements. The paper provides analysis of the experimental research results of masonry behaviour in a biaxial stress state at primary stresses of opposite signs; identifies masonry destruction mechanisms complying with the conditions of stress state. The work demonstrates the key role played by interface elements in the formation of masonry destruction processes. Based on destruction mechanisms deduced from experiments, there was developed a discrete model of masonry. A system of masonry strength criteria was proposed corresponding to the biaxial stress state conditions at primary stresses of opposite signs. For purposes of studying the elastic-plastic deformation and destruction of masonry, there was developed a technology of numerical experiment performance using calculation technologies with a stepwise tracking of stress-and-strain state, at step-by-step loading. The scope of this paper includes verification of modeling method and technology of numerical experiment at various parameters of interface elements defining binding between bricks and mortar.

The article deals with issues of the thermal cracking resistance in massive concrete and reinforced concrete structures during the building period. The paper lists the calculation results of the NPP reactor foundation mat thermal stressed state and thermal cracking resistance. The research also considers the concrete hardening temperature influence on its thermo-physical and deformation characteristics. The deformation criterion is used to calculate the concrete thermal cracking resistance. In addition, the paper focuses on the assignment of safe concrete pouring technological parameters in the winter period. Furthermore, the article estimates the necessity of the structure peripheral electric heating during the building period.

Masonry is a complex multicomponent composite consisting of dissimilar materials (brick / stone and mortar). Masonry deformation process under loading depends on the mechanical characteristics of the basic composite materials, as well as of the parameters of the elements defining binding between brick and mortar being the interface elements. Traditional methods of masonry modeling are based on the use of generalized ("effective") mechanical properties of the composite as a continuant homogeneous continuant medium. This paper presents an overview and analysis of continuant masonry models adequately reflecting the process of elastic, and in some cases elastic-plastic masonry deformation within the composition of stone structural elements. The paper provides analysis of the experimental research results of masonry behaviour in a biaxial stress state at primary stresses of opposite signs; identifies masonry destruction mechanisms complying with the conditions of stress state. The work demonstrates the key role played by interface elements in the formation of masonry destruction processes. Based on destruction mechanisms deduced from experiments, there was developed a discrete model of masonry. A system of masonry strength criteria was proposed corresponding to the biaxial stress state conditions at primary stresses of opposite signs. For purposes of studying the elastic-plastic deformation and destruction of masonry, there was developed a technology of numerical experiment performance using calculation technologies with a stepwise tracking of stress-and-strain state, at step-by-step loading. The scope of this paper includes verification of modeling method and technology of numerical experiment at various parameters of interface elements defining binding between bricks and mortar

This paper aims to study the distribution characteristics of the ratio of measured value and calculated value for ultimate bearing capacity, shaft resistance and tip resistance, and discuss the impact of shaft resistance and tip resistance on ultimate bearing capacity. A new performance function is proposed in terms of the three types of bearing capacity mentioned ahead. Take bored piles and driven piles for example, and the results from analysis indicate that the ratio of the measured value to calculated value of bored piles ranges from 0.75 to 1.45, and mostly is greater than 1.0; The ratio of the measured to predicted bearing capacity of driven piles lies between 0.8 and 1.5, and is larger than the corresponding ratio of bored piles. In addition, the reliability of tip resistance is lager than that of shaft resistance for bored pile, while the reliability of tip resistance is less than that of shaft resistance for driven piles. Meanwhile, the method presented in this paper can offer references to designers for revising and improving the technical code for pile foundations.

The bottom frame structure, with serious earthquake damage, occupies a large proportion in the houses collapsed in earthquakes. However, because it is economic and practical, it is still widely used. Based on the understanding of the seismic performance of bottom frame structure, this paper determines to study seismic measures of the bottom frame structure. The current seismic measures can be divided into two major categories: strengthening key components and avoiding key components, therefore this paper adopts the method of strengthening parts which are easy to collapse for reinforcement, under the premise of meeting the stiffness ratio between reasonable layers, adds wing wall to improve the capacity of resisting collapse of the structure and pinpoints the efficiency of adding wing wall in the capacity of resisting collapse through quantitative analysis. Although there are differences in the improvement of the capacity of resisting collapse under different seismic waves, adding wing walls reasonably can greatly improver the anti-collapse capacity of the structure..

This paper presents an experimental and computer analysis of an integral bridge structure exposed to a load caused by the horizontal pressure of water during floods. The paper focuses on the residual load-bearing capacity of an integral bridge structure that was able to withstand the effects of flooding. ​​Three models of integral bridges built to a scale of 1:5 were made for the purpose of testing. The frames have a span of 2.6 m, the thickness of the supports is 0.2 m, and the thickness of the deck in the middle is 0.125 m. The frames are loaded by horizontal forces representing the water pressure during floods. Each frame is securely anchored at the base and is gradually loaded by two horizontal forces situated in the corners of the frame. Loading is interrupted when cracks of 0.3 mm appear. Subsequently, the frame is loaded by a pair of vertical forces acting on the top surface of the frame, up to the load-bearing capacity. This procedure was established in order to find the residual load-bearing capacity of an integral bridge that managed to withstand the effects of flooding. . The paper includes a set of computer simulations.

Subgrade stress under static vehicle load is different from that under moving load. In order to study the law of subgrade dynamic stress under moving vehicle load, the paper established the three-dimensional analysis model with finite element software and calculated the subgrade dynamic stress of different depth. It is concluded that subgrade dynamic stress decreases with the increase of depth and the smaller the depth is, the faster the degradation is. To a certain depth, subgrade dynamic stress changes a little. Meanwhile, the paper analyzed the effect of surface layer modulus and thickness, roadbase modulus and the thickness, subgrade modulus on subgrade dynamic stress. It is concluded that surface layer modulus and thickness have little effect on subgrade dynamic stress , subgrade dynamic stress decreases when roadbase modulus and the thickness increase, especially for the depth of the subgrade is relatively small. Subgrade dynamic stress increases with the increase of subgrade modulus. Increase trend is more obvious when the depth is small.

Infilled wall is always regarded as a nonload bearing element, its energy-dissipation capacity and impact for the frame structure under earthquake have not been taken seriously. In this paper the function of infilled wall for frame structure was discussed, energy-dissipation capacity of different measures were analysed and compared from the point of passive control theory. This paper provides the reference for the further research of filler wall.

Based on the multi-layer elastic system theory, large general used finite element software is used to analysis in the paper. The pavement structure layer bottom three-direction maximal shear stress SXY, SYZ and SXZ are computed under the different axis load for four kind combinations. Through contrasting the three direction shear stress, the paper obtained some curves and laws about the pavement structure layer bottom three-direction shear stress along with the axis load change.

This paper presents a technology of sliding damping which could resist ground frost heaving. In the technology, setting the low-grade mortar bond of the upper and lower ring beams to achieve slip shock absorption, and setting the rubber beams to achieve shear deformation limiting. By rubber beam shear performance test, the shear strength of the rubber beam has been acquired. In the paper, the finite element software has been adopted to simulate the seismic performances of common wall and sliding damping wall structures under low cyclic reversed loading, the hysteretic curves between the bottom shear and the top displacement of the walls. The research results show that sliding damping ring beam has the very good function on dissipating seismic energy and reducing seismic action.

Mechanical behaviors of pile-soil effect and anchor-soil effect are significantly important in supporting engineering activities of foundation pit. In this paper, finite difference method (FDM) was utilized to perform the numerical simulation of pile-anchor system, composed of supporting piles and pre-stressed anchor cables. Numerical simulations were on the basis of the foundation pit of Jinan's West Railway Station, and 3D simulation analysis of foundation pit has been prepared during the whole processes of excavation, supporting and construction. The paper also analyzed the changes of bending moments of piles and axial forces of cables, and discussed mechanical behaviors of pile-anchor system, through comparisons with field monitoring. The results show that the parameters concluding vertical gridding's number, cohesion of pile and soil, and pile stiffness have robust influences on supporting elements' behaviors. Mechanical behaviors of supporting pile and axial forces of anchor cable changed dramatically, indicating that the potential failure form was converted from toppling failure to sliding failure., 4th International Conference on Civil Engineering, Architecture and Building Materials, CEABM 2014; Haikou; China; 24 May 2014 through 25 May 2014, Applied Mechanics and Materials, 580-583, pp.238-242; 2014

In this paper, we intended to replace the fluid-structure interaction of deep water bridge piers with acceleration-dependent forces during an earthquake. The hydrodynamic pressure on bridge pier groups under seismic excitation is studied using the finite volume method. Different seismic waves with various spectrum components are selected in order to cover frequently encountered cases. The calculated forces of these cylinders are fitted into the Morison equation, and by calculation, the drag force term is negligible, thus the effect of fluid is converted into one added mass term. The paper further calculated the dynamic response of a continuous beam bridge with pier groups in water to check the validity of our proposed method.

This paper analyzes the causes of larger differences of final settlement calculated value of cement fly-ash gravel pile (CFG pile) composite foundation of Baotou with actual observed result of it. On the basis of analysis on a number of practical engineering data of Baotou, we modify the settlement formula of the CFG pile composite foundation and gain the modified coefficient applied to the settlement calculation of the CFG pile composite foundation of Baotou. The modified formula and coefficient proposed in this paper have a positive effect on the accurate settlement calculation of puting forward a more accurate correction formula and coefficient of the calculation of the CFG pile composite foundation of Baotou.

This paper studied on the underwater vibrating compaction technology of scattering-filling rubble stone layer. At HongKong-Zhuhai-Macao bridge project, in order to satisfy the project time limit, underwater vibrating compaction technology with hydraulic hammer instead of conventional dynamic compaction technology was used to tamp scattering-filling rubble stone layer with no dead angle in a short time. Owing to the shortage of engineering example, the theoretical analysis was needed before field application. In this paper, the rubble stone layer and the vibration system were simplified to a mechanical model. Vibration system’s work on rubble stone was obtained by mathematical derivation, and effects of parameters were analyzed. The result shows that work on scattering-filling rubble stone layer increases with the increase of system quality, equivalent damping, exciting force and angular velocity and decreases with the increase of equivalent stiffness, water stiffness and buoyancy.

This paper studies the forming condition,reinforcement mechanism and failure condition of composite foundation, and summarizes the failure mode under horizontal load, at the end of the paper, based on these theory,the p-y Curve which Concerned with the reinforcement mechanism analysis and calculation of composite foundation has been studied.

When the scaffold construction method is applied on long-span steel trussed arch bridges, reasonable setting of the temporary pier elevation has significant influence on assembly linearis and safety assembly of long-span steel trussed arch bridges with semi-cantilever. In this paper, in accordance with the manufacturing linearis steel trussed beam bridge and steel truss beam linearis changing during building process, the calculation of temporary pier elevation was studied systematically, and practical function was deduced. Then, the method was applied to a long-span steel trussed arch bridge. The obtained result by in-situ assembly and dismantling presents that: 50 mm preserved method is considered in this paper, which can provide convenience for removing the temporary pier. At the same time, the rationality and reliability of the presented approach are verified. It also can provide reference for similar bridge construction.

The plane finite element analysis is mostly adopted in soft rock tunnel excavation instead of three-dimensional nonlinear finite element analysis at present, but almost every underground engineering is a spatial nonlinear problem which, in many cases, cannot be simplified into a plane problem. This paper presents a three-dimensional elastic-plastic finite element analysis of incremental variable plastic in soft rock tunnel excavation, through analyzing the tunnel excavation and support, and combining the incremental variable plastic stiffness method into three-dimensional elastic-plastic model in light of the advantage of increment variable stiffness method and the incremental additional load method. Simulation results show that, the three-dimensional elastic-plastic finite element analysis model presented in this paper changes little final deformation under different load release coefficients, together with small support stress.

Uplift capacity is the main design control parameter of tower foundations. There are many factors to be considered in the design of tower foundations, such as the choice of models and the combination of different factors. The research on the uplift capacity of tower foundation is mainly focused on the foundations built on flat ground, while there is no mature method for the tower foundations placed in sloping ground. Base on the theory of earth pressure and the Mohr Coulomb law, This paper tries to establish the equations to calculate the uplift capacity of tower foundation placed in sloping ground and get the equation to obtain the effective value of the uplift depth for the tower foundation. At the end of the paper, a calculation example is presented using the simplified equation.

This paper summarizes the basic design of reinforced concrete segment for cross river shield tunnel in gas pipeline project, meanwhile discusses its assembly style and water-proof technique. One loop of shield tunnel is divided into six pieces of precast reinforced concrete segment which is assembled with screw bolt and stud. In addition, Waterproof technique such as self-waterproof of segment, elastic rubber gasket and water swelling rubber strip is used to ensure waterproof performance of shield tunnel. The presentation of this paper may provide guidance for the design of reinforced concrete segment for cross river shield tunnel.

The stability analysis and evaluation on high slope is of great significance. The stability analysis on the slope of ZHANG-ZHUO highway is carried on in this paper by using the strength reduction method and ABAQUS software. According to the stress and plastic deformation calculated by ABAQUS software, the paper gives evaluations for the stability of slope. It turns out that safety factor of the slope is greater than three; the stability of the slope is well.

The main purpose of this paper is to study the seismic performance of prestressed reinforced concrete pile (PRC pile) reinforced with nonprestressed reinforcements. Two prestressed high strength concrete piles (PHC piles) and two PRC piles were tested. The variables studied in this research are the prestressed reinforcements ratio and nonprestressed reinforcements ratio. The piles subjected to low-cycle loading were presented in this paper, including the hysteretic performance, stiffness degradation curves, coefficient of equivalent viscous damping and skeleton-frame curves. It is shown that the failure modes of all specimens are bending damage from the test and PRC piles have good energy-absorbing hysteretic behavior.

On the basis of plastic-elastic mechanics and finite element method, one selected 150m high reinforced concrete chimney was taken as the target in this paper to analyze the mechanical condition of directional demolition blasting, the capsizing time, the internal force of support abutment and constitutive relation of the chimney during directional blasting. A finite element model of the towering reinforced concrete chimney was established through separated modeling method by finite element analysis software LS-DYNA of ANSYS. Results show that the constitutive relation given by this paper conforms to reality. The finite element model of the towering reinforced concrete chimney established by separated modeling method is reasonable. The real overturn process, capsizing location and capsizing length of towering reinforced concrete chimney during directional demolition blasting are agree with that of numerical simulation.

CFRP is a new kind of building materials popularly used in structure strengthening. In order to study the reinforcement technique for masonry walls of school buildings, the walls with window opening strengthened by CFRP were studied in the paper. Based on the experiment result, the finite element simulation and theoretical calculation analysis were done to study the mechanical behavior and shear capacity of the wall with window opening reinforced by CFRP. The CFRP pasted at the corner of window opening were proved to be effectively in improving shear capacity of the walls, and simple calculation formulas of shear capacity were provided in the paper, which proved to be accurate.

This paper points out the characteristics of composite shear walls with double steel plates and filled concrete and composite structure force mechanism. This paper briefly expounds the present situation of the research on the seismic behavior of composite shear walls with double steel plates and filled concrete from four aspects including structural experiments, calculating method , calculating theory and local stability, and analyzes the shortcomings in the research. After comparing many achievements, this paper puts forward several key problems in the research of seismic behavior of composite shear walls with double steel plates and filled concrete. Finally, the development of the seismic behavior of composite shear walls with double steel plates and filled concrete is prospected.

Based on Vesic theory of cavity expansion and Mohr-Coulomb yield criterion,A method was proposed which can be used to calculate earth pressure around circular section static compaction pile.Furthermore, a formula calculating earth pressure around circular section static compaction pile with horizontal displacement was deduced based on hyothesis without relative displacement on pile-soil contact boundary.Finally,according to the research above and force balance condition,an estimation method for horizontal bearing capacity of circular section static compaction pile was gotten.In order to validate the feasibility proposed theory in this paper, a comparative research was carried out.Both experimental and theoretical results indicated that earth pressure on pile-soil contact surface of soil compaction pile was much more than of pile without soil compaction and earth pressure would redistribute with change of horizontal displacement.Moreove,because horizontal bearing capacity calculated by method in this paper accorded with result measured in field very much,the theory in here was feasible.

Foundations are often subjected to complex dynamic stresses which result from ocean wave, vehicle or seismic loads. In this paper, four series of tests under different dynamic stress paths were carried out on Fujian standard sand with hollow cylinder apparatus, to investigate its liquefaction resistance. Test results showed different strength of specimens under different dynamic stress paths, when using the traditional evaluation index: maximum cyclic shear stress. A concept named as load efficiency (E) was proposed in this paper, which is defined as definite integral of dynamic shear stress on time in a single cycle.Eis a new parameter to characterize liquefaction resistance of non-cohesive soil, attempting to normalize the effect of different shear modes, in which the shear stresses are constant or change periodically under different dynamic stress paths. Test results showed that in the isotropic consolidation condition, the relationship betweenEand failure cycleNfis nearly linear in the dual-log coordinate.

Through analysis and comparison of some nonlinear seismic response analysis models for structures of bridges with pile foundation, considering the effect of deformation performance of pile foundation whose nonlinear properties of foundation and the component are taken into account, this paper presents an improved model relatively. In order to verify the rationality of the improved model proposed in this paper, the calculation and analyses of the test model of a single pier with pile foundation through pushover are done, and the results are compared with the experiment results.The pile foundation does not damaged under seismic load; The improved model can reflect material nonlinearity of the actual soil contact between soil and pile, and the dispersed spring model can be better to simulate the postural nonlinear of pile-soil contact and separation; at the same time, we need to consider vertical friction spring in the pile side.

Seismic fortification intensity has been adjusted in some areas which were affected in The Wenchuan-earthquake. It was seismic strengthening for most of the buildings especially the public buildings after the adjustment. In order to ensure the seismic performance of the structure after reinforcement ,the analysis method based on performance is gradually applied in the large and complex engineering structure analysis .The paper uses a large span Sports Training Center under construction as background. According to the situation that the fortification intensity by 6 degrees improved to 7 degrees ,the paper uses Push-over method to analysis elastic-plastic of the finite element models ,which including the mild steel damper before and after reinforcement ,under the action of the rare earthquake of 7 degrees. The paper is studying the internal force,deformation and destruction of the structure in the action of the rare earthquake,comparing the dynamic characteristics and seismic performance of the models, and researching distribution of weak links and plastic hinge of the models under the large earthquake. The results show that the models can meet collapse resistant checks less than 7 degrees of the rare earthquake before and after reinforcement. The second floor is relatively weak of the original structure,and can emerge local damage easily. But the structures stiffness is more uniformly after reinforcement, and has large resistance of the collapsed ability.

This paper based on a foundation pit in Tianjin shown the monitoring data and simulated the excavation process by finite element software ABAQUS. The lateral and vertical displacement of the top of slope obtained by calculating at different excavation stages were compared with the measured values. At last this paper made a conclusion about the deformation rules in the process of excavation, which can provide reference for design and construction of similar engineering.

Songhua River Bridge is an important large concrete bridge engineering in China. Because it is located in complex environment, the reinforcing steel rust, freeze-thaw, artificial damage and washout will result in performance degradation of the concrete structure. The paper firstly invested the climatic environment and local corrosion environment. Then, according to the environment characters, studied the structure endurance degradation regulation combining the laboratory simulation tests and natural exposive tests. Made a group of concrete test specimens according to the true construction field material mixture ratio. The field experiments include air exposure, half soaking and full soaking tests. And the laboratory tests include freeze-thaw test, salt aspic test, chloride ion penetrant test, carbonization test, etc. Through test research, the paper gripped the degradation regulation of bridge concrete property. Then constructed the bridge concrete endurance degradation model, established the theoretical foundation for predict the large bridge service life.

This paper focuses on stability analysis of an artificial rock mass slope by a nonlinear finite element method (FEM). For a long time, rock slope stability problem is always an important research issue in the field of geotechnical engineering, which is related to human life and property safety as well as engineering security and efficiency. Therefore, the stability analysis and evaluation on rock slope is of great significance. The static and dynamic stability analysis on the artificial rock mass slope of WuAn power plant in China is carried on respectively in this paper by using the strength reduction method and FLAC3D software. In this analysis, static and dynamic instability criterions are enumerated, and the static and dynamic safety factors are calculated with the developed criterions of the displacement mutation, respectively. The analysis results show that the artificial rock mass slope is basically stable. It indicates that analyzing slope stability with strength reduction method is feasible.

Shear displacement method is used to predict the settlement of the grouted pile in this paper. An empirical relationship is used to determine the improvement of shear modulus for the soil around the grouted pile. A parameter is also proposed to represent the improvement of the shear modulus for the grouted soil at the pile tip. Shear displacement method is modified to consider the influence of grouting. The detailed calculation process of the method is described and determine of the parameter is also given in the paper.

In order to confirm the calculation model of multi-ribbed slab structure and transmission of earthquake action, this paper improved existing multi-ribbed slab structure. The calculation model of improved multi-ribbed slab structure confirmed the stress relationship among three seismic fortification lines, and the transmission of earthquake action became clear, the same calculation model could be applied in structural analysis. For studying the effect of characteristic parameters of restoring force changing in the second seismic fortification line on seismic performance, and correcting the parameters, this paper analyze push-over model of the second seismic fortification line to get the static pushover curve. According to the study, the amount of steel bar in grid column and sectional dimensions of grid beam made the major effect on characteristic parameters of restoring force in the second seismic fortification line. The growth of steel bar’s sectional area in grid framework and the yield strength are mainly in direct proportion. It is more reasonable that simultaneously alter steel bar’s sectional area in grid frame and dimensions of grid framework to adjust characteristic parameters of restoring force changing in the second seismic fortification line.

An asymmetric twin arched tunnel is designed to meet the line development of triple track railway in accordance with ground geological condition and topography in this paper. A partition wall is adopted to support the double arches of the tunnel, and the pilot drift and bench cut method is utilized to preserve the safe excavation of the double arch tunnel in poor rock mass in the paper. The design technique and construction method may guide the driving of such tunnels under similar condition.

The effects on rigid pile composite foundation caused by lateral unloading in horizontal direction are studied in this paper. Considering the excavation of neighborhood deep foundation ditch, a calculation model for the composite foundation is proposed and the theoretical formula of pile deformation is given. Furthermore, the formula of bending moment of the pile in the composite foundation is deduced in this paper.

The effective reinforcement depth is one of the most important parameters of dynamic compaction method design and construction, so far it is still lack of in-depth theoretical study. In this paper, combined with the field test, FLAC3D was used to do the numerical simulation of dynamic compaction reinforcement to cohesionless soil. By the simulation, this paper analyzed the factors which may influence the effective reinforcement depth, such as the hammers weight, drop distance, base area, and the soil parameters. The orthogonal design method was used to analyze the soil parameters sensitivity to the effective reinforcement depth. Combined with the results of numerical analysis and the traditional empirical formulae, the effective reinforcement depth calculation formula was established for cohesionless soil. Engineering verification shows that, the results estimated by the formula is reliable, and can provide certain reference for the future engineering.

The strength properties of the rock under unloading conditions are essentially different from the rock under loading conditions. At present, the study on the mechanical properties of unloading rock mass is common, but the research for unloading strength properties of jointed rock mass, especially the influence of structural plane on unloading strength is seldom. The paper studied the failure characters of unloading rock mass, and the influences of structural plane properties on unloading strength based on triaxial test are considered emphatically. Finally the strength criterion of unloading rock mass is proposed in this paper.

In order to find out the loading mechanism of Fly-Ash-Flushed-by-Seawater base asphalt pavement under heavy load and verify reasonable road pavement structure, this paper analysed the road model under different axel load with ABAQUS. The influence of structural stress and the road asphalt pavement deflection in different road structural parameters were shown in the paper. The result indicates that the structural stress and the deflection under heavy load are greater than they are under the standard load. When the vehicle is over load by 100％, the tensile stress of subbase is close to the allowable tensile stress. The structure of Fly-Ash-Flushed-by-Seawater base asphalt pavement can be designed to adapt to the over load traffic of Yingkou by adjusted the structural parameter in a certain range.

This paper presents the latest developments of a simple method used to determine the ultimate load of two-way simply supported reinforced concrete slabs. Based on the reinforcement ratio, two failure criteria are proposed in the paper. The effectiveness of the developed model is validated through satisfactory comparison with from test results.

The paper established 3-D finite element model, studied the response pattern of rigid pile composite foundation under earthquake loading with time history analysis method. According to similarity theory, this paper established rigid pile composite foundation pile group model, analyzed the response pattern of it with pseudo-dynamic test methods. And compared and analyzed the results which were obtained by different methods, based on these analyses, some conclusions which may be of some value for anti-seismic design of this type of composite foundations are drawn

The transfer structure with web column is a new transfer structure form.The stiffness of the story was changed to analyze the influence of seismic behavior on structure in this paper, and then, the analytical result of such structure under seismic action is also discussed by using PKPM and ANSYS(FEM) , It shows that the structure can clearly improve the bearing capacity ，and some advices are given in this paper for designing this transfer structure too .