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This work aims to study the prediction of bearing capacity of prestressed concrete beams subjected to accelerated corrosion process using Machine Learning (ML) techniques. After data collection, the results were used to model the behavior of flexural stress, and predict their final load capacity, considering position, length, and width of the cracks generated by corrosion as well as loss of bearing capacity. The study presents an analysis of 363 days old beams damaged by corrosion, connected to a galvanostat for 62, and 121 days to make faster the process. Six beams were analyzed; five of them were used to train the model, the other works as a basis to compare the results thrown by the model with the real data. After the treat, the results showed that Bagged Trees Model fits better to real data, it was seen that removing atypical data improves the correlation of predicted and real data. The actual data were compared with two different prediction analyzes; for the first one, the atypical data were not removed; in the second one, the atypical data were eliminated with a statistical analysis. Obtaining relative error percentages of 15.18%, 14.59%, presenting two predictions: final load of 1444 kg and 1126 kg. Which means a resistant moment of 650 T-m, and 506.7 T-m respectively, taking as a prediction the second value in the safe side.

Today the requirements for concrete restoration are not only aspects of retrofitting or restoration of bearing capacity but increasingly aspects of preservation of historic structures, such as industrial monuments, civil engineering structures and buildings of the 60s. The Polymer modified self-compacting concrete (PSCC) is a suitable material to be applied in this field, as it not only has excellent mechanical properties (e.g. high bond strength, low Young's modulus) but it is also possible to imitate colours and textures similar to those of the original surfaces. PSCC is therefore an interesting alternative to well established materials, such as PCC, sprayable PCC (SPCC) and shotcrete.Presented in this paper are the results of the further development of PSCC for a particular scenario where due to limited accessibility, the application method and therefore the mix design had to be optimised. Characteristic fresh and hardened concrete properties were investigated and special attention was given to deviation of the fresh concrete with regard to variations in the amounts of source materials.It is shown that although PSCC is a high-performance material, dosage of its source materials, mixing and application of the material itself can be done with simple conventional building site equipment. At the same time a robust fresh concrete as well as excellent surface properties of the hardened concrete can be obtained. Purpose-made mix designs can be developed for various applications with excellent results in performance and appearance.

Composite slabs with prepressed embossments present an effective solution for horizontal load bearing structures. Sheeting serves as a formwork in construction stage and as a tension bearing member after hardening of concrete. There is no need for additional tensile reinforcement in case of sufficient longitudinal shear bearing capacity of the embossments. Longitudinal shear bearing capacity is not precisely determined when designing according to nowadays standards. Full scale bending tests of the slabs are used to determine characteristics for m – k method or partial connection method. Bending tests are expensive and space demanding. Alternatively small-scale shear tests can be used to determine shear characteristics of the sheeting. However, shear tests cannot include all the effects affecting the bearing capacity of bended slab, such as effect of curvature or distribution of load. Therefore, related design method has to be used to determine load bearing capacity of the slab in bending. This paper extends achievements presented by the authors in contribution in CRRB 2013. The results of small-scale tests are compared with results of numerical models of the slab in shear. Numerical models are created in two different finite element codes. Setting of steel-concrete interface properties in the models is validated using data from literature.

In order to reduce the temperature and drying shrinkage cracking in cement concrete pavement, setting up cracks which becomes the weakest part of the cement concrete pavement. Load transfer behavior of cracking has a great influence on road performance and used lifetime in cement concrete pavement. The improvement of load transfer behavior of cracking is conducive to maintain effective load transfer between the pavement and to enhanced bearing capacity of pavement structure, also to reduce the damage of the structure, which is an important technical approach to extend the used lifetime of pavement. This paper describes the mechanism of load transfer and research status of crack, and points out the problems existing in the crack load transfer ability of research and development trend.

This paper focuses on the the relationship between strength and ductility of high-strength concrete (HSC) columns with high-strength aseismic transverse reinforcement under concentric compression and its influencing factors. Some confining models for HSC with high-strength aseismic transverse reinforcement are introduced. Based on 10 groups of high-strength aseismic stirrup confined high-strength concrete square columns are tested under concentric compression, the influence of stirrup in binding strength and the ductility of concrete columns on different stirrup strength, different volume ratio of reinforcement, different stirrups type and different stirrup spacing form is studied by using finite element software ABAQUS. The results indicate that a good agreement is obtained between calculated results and experimental ones. The high-strength stirrup confined concrete columns can improve the bearing capacity and deformation performance of components effectively, laying the foundation of the applications of high-strength stirrups in concrete structures.

Granulated Blast furnace Slag (GBS) has good potential to be use as granular material in place of conventional granular materials i.e. sand and aggregate. It can be use as structural fill in low laying areas. In such cases, it is required to evaluate the bearing capacity of the fill and reinforced it with some suitable reinforcing materials to enhance the bearing capacity. In this study, Response of circular footing was studied by using GBS as fill material and geogrid as reinforcing material. Only one geometric parameter i.e. number of geogrid layers was considered to get the response of circular footing. Two numbers of geogrid layers were obtained as optimum parameters and it increases the ultimate bearing capacity 94% and decreases the settlement by 45% as compared to unreinforced GBS bed.

Due to mechanical performances of brace and steel plate, mechanical properties of semi-rigid joints and its construction and installation, semi-rigid steel frame-braced steel plate shear wall system is proposed. Nonlinear static analysis with parameters (thickness of plate, type of brace, size of brace and the ratio of span to height) changed of a single-span and single-floor semi-rigid steel frame-braced steel plate shear wall system illustrates that braced steel plate shear walls contributes obviously to bearing capacity and lateral rigidity of semi-rigid steel frame. Also, the finite element analysis (by ANSYS) show that semi-rigid steel frame-braced steel plate shear wall system has excellent ductility.

The paper presents the application of methodology for the assessment of reliability and structural load bearing capacity using advanced methods of probabilistic FEM analysis in combination with mathematical modelling of degradation processes of concrete and reinforcement. The durability, serviceability and ultimate limit states are assessed. The authors deal with the validation of load bearing capacity of the bridge on the 3rd class road built in the 1st quarter of 20th century in the Czech Republic. Regarding the reliability requirements according to Standards and, considering the current state of the structure, the actual value of load bearing capacity is assessed. By reason of the time-consuming FEM analyses the stratified Latin Hypercube Sampling (LHS) method is used for generation of input random variables.

Pretensioned concrete beams are used as a main load bearing member for composite bridges with a span to 30 m. The advantage of longitudinal prefabrication technology of beams for small span bridges is quick installation, savings of straight supporting scaffolding of centers and formwork. The amount of labour with formwork, reinforcement and concrete including work with scaffolding of centers on site is reduced at a minimum. During searching applications of steel fiber reinforced concrete (SFRC) suitable for this kind of structure a pretensioned concrete beam suitable for a bridge bay with a span from 12 to 15 m has been chosen for an investigation. Three types of beam were manufactured for experimental tests. The beams were supposed to be a part of a bridge bay with a composite slab. These pretensioned beams were made of SFRC. In case of the experimental tests, a cast-in place concrete cover from plain concrete was casted on the top of the beams. The cast-in place concrete cover simulated a top composite slab. The bearing capacity of the beams with the cast-in place concrete cover was tested until their destruction. The tested beams showed higher bearing capacity than it was determined by a theoretical calculation. The beams also demonstrated high safety against collapse during structure overloading. The process of the experimental testing was also simulated on a numerical nonlinear model and then the results were compared. The result comparison of the both types of tests did not show any significant irregularities.

The paper deals with a system of precast floor plates from lightweight concrete intended mainly for building of family houses and residential construction. The developed system has two types of precast floor plates made from lightweight concrete: floor plates for floor systems and solid section floor plates. This paper describes solid section floor plates. The unambiguous advantage of lightweight concrete floor construction is weight lower by as much as 37% compared to floor structure made from common concrete, while bearing strength remains unchanged as well as high fire resistance. This type of floor slabs has also been successful in the system of assembled prefabricated houses thanks to its lower weight and elimination of the wet construction process.

This article deals with the issues of designing the detail of the dapped-end beam, the design of which in practice usually employs the design method based on the strut-and-tie method. The most usual method for its reinforcing is described herein, including the selected suggestions that are mentioned in the literature. The article also presents the experiment carried out to verify the design method. A study shows the influence of the used amount of vertical and inclined hanger reinforcement on the bearing capacity and behaviour of the detail under load. The results show fairly good correspondence between the bearing capacity as determined by calculation and by the experiment. They also point out to the adequacy of using the inclined hanger reinforcement in relation to formation, development and final width of the cracks.

Greenhouse rolling machine is an important equipment of modern agriculture. It is widely used for curtain rolling in greenhouse. The overall structure of greenhouse rolling machine is designed. It uses composite gear system. According to its mechanical requirement, the machine transmission gear materials, steel 45 and 20CrMnTi alloy steel, are selected out. In order to improve the materials’ mechanical property, the materials have been treated by heat. The mechanical property, such as hardness, strength, toughness, etc, when quenching and tempering at different temperatures, is studied. The result provides a theoretical basis for the design of bearing capacity of the rolling machine.

Steel tubular column filled with steel-reinforced high-strength concrete (STSRHC) has higher bearing capacity and seismic performance, so STSRHC has a good application prospect in Engineering. So far, it is in the stage of research. To calculate the bending bearing capacity of steel tubular column filled with steel-reinforced high-strength concrete (STSRC), the bending resistance of STSRHC is predicted by the method of plastic stress distribution, and the formula of bending bearing capacity is successfully established. The results show that the calculated results based on the plastic stress distribution method and the experimental ones are in agreement well, and the formula can be used into columns that have different section form of inserted steel. The conclusions have a guiding significance on improving other performances of STSRHC.

In the research, Polytetrafluoroethene (PTFE) is applied in a newly elastic composite cylindrical roller bearing, i.e. PTFE is modified into the traditional hollow cylindrical roller bearing so as to improve the vibration, wearing properties and life span of the roller bearing. The results show that bearing capacity of the same dimension of WF/PTFE composite materials is higher than that of WP/PTFE composite materials. Small dimension of WF-PTFE composite materials has the best wearing properties under light load conditions; large dimension of WF-PTFE composite materials has better bearing capacity and wearing properties than small dimension of WF filler under heavy load conditions. Compare to traditional method, Rolling stress improves by filler PTFE materials using our method reduces by 17.1% under light load conditions and reduces by 27.7% under heavy load conditions. The research provides basis for the modified material of the elastic composite cylindrical roller bearing.

Most of the existing building floor roof of brick structure is precast floor slab structures, which structural integrity is not good. In the earthquake, the floor is easy to fall off from the wall, causing casualties and economic losses. Vertical bearing capacity of precast floor slab are usually able to meet the requirements. In most cases the floors have been fall off from the wall before the floors were damaged, Stability of the outer plane of the floor itself to be adequate.By analyzing the patterns and characteristics of precast floor slabs crack under seismic force often appear, this paper presents that the prefabricated floor flat overall reinforcement scheme, which the application of steel band with end portion of the floor a holistic reinforcement,and finite element software ABAQUS be counted cases,the integrity of the reinforced floor to achieve significant improvement, and maximum allowable displacement can be controlled within a limited value.

Model tests are performed to study the working properties of reinforced and non-reinforced gravel cushion on soft subsoil. The effects are analyzed of reinforced materials on the bearing characteristic of the cushion. The stress field and settlement field are studied through the method of numerical simulation. The results show that: The bearing capacity of foundation with cushion increases significantly when the cushion is reinforced. Under the same condition, the effect of geocell reinforcement is better than geogrid reinforcement. The value of coefficient of subgrade reaction increases when the cushion is reinforced. The reinforced materials can adjust the stress distribution and settlement distribution of the cushion.

At present, many analysis methods and calculation formulas of the bearing capacity of concrete filled steel tubular columns have been researched. But these numerous calculation formulas of the bearing capacity have varied forms, and the application scope and the calculation precision of them are also quite different, which makes it difficult and confused for engineering designer to choose a suitable formula. Primary calculation formulas of the bearing capacity of concrete filled steel tubular columns are summarized. The calculation results of these formulas are compared with some test results of the concrete filled steel tubular columns with a large diameter. The applicability and the accuracy of these formulas are analyzed. Based on these comparisons and analyses, reasonable suggestion is given to select the suitable formula. Finally, one formula is provided to calculate the ultimate bearing capacity of concrete filled steel tubular columns reinforced with steel bars.

There are many bridge in our country, the new bridge has been built and numerous. Accurately and efficiently assess the bridge state to determine its carrying capacity and reliability level of great social and economic significance. Bridge load test can be directly measured structural properties of the bridge to provide a basis for the evaluation index maintenance of the bridge structure. Currently, the basic architecture using load bearing capacity performance test results assessed the bridge has been established, but many details are still unresolved issues still need to be further expanded research to accurately determine the fine actual carrying capacity of the bridge.

The bearing capacity calculation in horizontal and safety assessment methods of high-pile pier slideway while large platform dragged horizontally to move to barge was studied based on the theoretic derivation and numerical simulation method. According to the research, the load effect of 6000ton slideway in the process of large platform dragged horizontally is obtained, the safety of slideway is evaluated, and the safety measures of slideway structure which should be taken during dragging platform are recommended. The results of the calculation and analysis show that the bearing capacity of slideway meet the requirements of design under the horizontal load of 11550kN by using uniform force to calculate, and the displacement is less than the width of the structure gap between two segments. The 6000ton sildeway is safe under horizontal load of 11550kN. These conclusions can provide the basis for the safety state analysis of high-pile pier slideway structure and the optimization of plan to move the large platform to load on barge.

Marine geotechnical investigation techniques provide important support for maritime salvage project. when using the new technology of pile rooting to righting shipwrecks, marine geotechnical investigation can provide a detailed physical and mechanical properties with reasonable parameters, and then use of splines curves and inverse distance weighting method to apply parameters to each pile, then analysis of the vertical uplift and compressive bearing capacity based on API standard, analysis of the level of resistance and strain relations based on P-Y curve method, predict drivability of piles and so on.

A laboratory model test of tunnel anchor was conducted to investigate its pullout mechanism and bearing capacity. Surface and rock deformation, strain and stress were measured during the entire model test process. The results show that: under pull out load, tensile failure first occurs in top surface rock near the anchor, then shear failure occurs in anchor-rock interface and rock around the anchor. The failure surface is inverted cone from the anchor bottom. Under 50 times design cable force tunnel rock is in elastic stage, suggesting that current tunnel anchor design is quite conservative and can be further optimized.

The safety of reinforced concrete structures will be impacted by the explosions. Using the calculations result of finite element analysis software, combining with database technology, a security level evaluation platform of blasting damage in reinforced concrete structures is established. The platform assesses the safety of damaged structure from the remaining bearing capacity, maximum crack width and maximum deflection, etc. It gives the security level from different aspects of the structure and the integrated security level, and repair advice.

Steel roof grid was detected and static analyzed. The grid was retrofitted because bearing capacity and rigidity of some steel pipes can’t meet requirement provided in codes. Method to reinforce the steel grid is adding pipes section area and replacing pipes with improved double-tube buckling restrained members. Analyze seismic behaviors of retrofitted grid using ANSYS software.

First, conducting static load tests for a 5 span bridge, then carry on application research for the bridge based on the embedded carbon fiber (CFRP) reinforced flexural reinforcement aiming at the shortcomings of its flexural properties, At last, the effectiveness of strengthening reinforced concrete beam that reinforcement by embedded CFRP has been discussed. The results show that embedded CFRP reinforcement beam can make full use of the characteristics of high strength of CFRP, which can improved obviously the capacity of the reinforced beam and the maximum increased capacity can reach 13.2%. In addition, the application of the embedded CFRP reinforcement technology has been discussed, which provides a meaningful reference for the development of the technology.

An experiment was performed about the bearing capacity of cold-formed thin-walled steel-OSB composite floor by the sand heap. The strain and deflection response of OSB board and steel beam is analyzed under the load; then the test process is simulated by ANSYS, the results of simulation are agreed with the experiment basically. Through the analysis of experiment and finite element simulation, the results indicate that the composite floor has enough bearing capacity and meets the requirement of the residential building completely.

A new type of concrete-filled square steel tubular column to steel-encased concrete composite beam joint is proposed. In order to study the influences of parameters on bearing capacity for the joint formed plastic hinge in the beam end, nonlinear finite element analysis under monotonic loading is conducted by software ANSYS. The results show that axial compression ratio has little influence on joint bearing capacity, and with the increasing of it, the bearing capacity is enhanced slightly. The height of U-shape steel has a significant impact on joint bearing capacity, and with the rise of it, the bearing capacity is enhanced obviously. The thickness of U-shape steel has a comparatively obvious effect on joint bearing capacity with certain limits, and with the growth of it, the bearing capacity of the joint is also grown observably. The diameter of longitudinal reinforcement in the flange slab of beam has some effects on joint bearing capacity, and with the improvement of diameter, the bearing capacity is achieved.

Three types of tip-structure include open-end, semi-closed and full close are tested to verify the feasibility of improving the ultimate bearing capacity in stiff clay layer. Driving pile trials are carried out in the site. This paper presents the analysis of set, driving stresses and bearing capacity according to the survey of set, driving monitoring, high strain dynamic test and the axial compression static test. It is proved that the closed end is the most feasible structure in stiff clay layer.

Purlin connections have important influence on the stiffness, bearing capacity and the purlin calculation methods. A new kind of purlin connection was put forward in this paper. The mechanical behavior of the new connection was studied by finite element analysis using software ANSYS. As can be seen from the simulation results, the new connection can enhance the stiffness of purlin, and effect of each new wave connection is better than the promotion of purlin stiffness in the vibration wave connection. New connection has a better promotion effect for small stiffness of purlin.

H-beam is usually used as column structure of single industrial workshop, steel column will inevitably encounter lateral impact of lifting weights or factory vehicle in the process of daily production, causing its defects in material and geometry, thus the change of axial bearing capacity.This aratical takes H-shaped steel column of a factory as the research object, establishes its residual bearing capacity theory of finite element analysis model in different situations under the impact using ABAQUS software platform, discusses the load parameters analysis in axial force-impac and Launches the functional relation between axial compression ratio and impact energy, providing a basis for assessing the residual loading capacity of such members after the impact.

The fire resistance of concrete filled steel tubular column is usually obtained by the numerical analysis method, which is difficult to operate and not convenient in the actual civil engineering. So it is necessary to study the simplified calculation method. A large number of numerical simulation results of the temperature distribution of the section and the bearing capacity at high temperature of the concrete filled steel tubular columns are analyzed. The influences of secondary parameters are simplified. The simplified calculation method at 150 min and 180 min for the bearing capacity at high temperature of concrete filled steel tubular columns subjected to axial compression and fire is presented on the basis of comprehensive analysis of the numerical calculation results. The calculation results can be used as the basis to judge the fire resistance. It is shown by the comparison with the experimental results that the precision of the simplified calculation method can meet the requirements of engineering application.

Concrete-filled rectangular steel tube four sides restraint effect on the core concrete was weaker than the corner, which made the effect not significant. The paper studied a new kind of stiffening rib –PBL stiffener to strengthen restraint effect of concrete-filled rectangular steel tube , and evaluated its advantages compared with other stiffening ribs. 9 PBL stiffened concrete-filled rectangular steel tube columns under axial compressive load were tested. It also collected the test with other stiffened rids, such as straight ribs, binding bars, knee brace, steel reinforcement cage, steel bar stiffeners, saw tooth shaped stiffeners, stitching straight stiffeners and no rib concrete filled rectangular steel tube to compare. It evaluated increasing coefficient of bearing capacity by stiffening ribs. The results showed that: the PBL stiffeners and binding bar of concrete-filled rectangular steel tube bearing capacity was greater than other reinforcement measures by more than 20%; PBL stiffener could be a new prominent type of stiffener because of its excellent mechanical performance and simple construction.

In practice, adhesive bonded joints are loaded by different intensity and rate. In the case where bond bearing capacity is exceeded, failure occurs. One of the affecting factors is strain rate. In the laboratory tests, ČSN EN 1465 is used as a basic standard, specifying the rate of deformation in the interval of 65±20 seconds. The goal of this research is to describe the behaviour of two-part epoxy adhesives at different strain rate of bonded joints. Experiments evaluated the changes of bond strength, deformation and time to failure. Time to failure is particularly significant because of the potential consequences of fast structural joint violation.

Technology methods of cast-in-place pile post grouting has the advantages of easy operation, good reliability, low cost and bearing capacity growth. In order to study and demonstrate the method on bearing capacity level of cast-in-place pile, a series of tests including of vertical static loading test and horizontal static loading test were used in the job. Some testing results were obtained from the tests.

Concrete filled double skins steel tube is a new components which is based on concrete filled steel tubular and use inner steel tube instead of core concrete. The components have many advantages such as little weight, good resistance for earthquake, good stiffness for resist bending and good performance for resist fire, and has been used in bridge pier, high-rise buildings, power transmission tower and so on. While these structures may inevitably suffer impact which comes from vehicles, ships, aircraft, etc. the structures which is impacted have taken much attention. This article will analysis dynamic behavior of concrete filled double steel tube under impact with simply supported, and propose formula of dynamic bearing capacity, laid the foundation for the analysis of impact performance of CFDST.

A mall large roof rack has been used 17 years. Because of upgrade, addition of decorate load, and missing the original design drawings, the spatial site test and check calculation of bearing capacity will have to be done. Using some detection tools, we can get arrangement, size, displacement, deformation, etc. And we can sue 3d3s software of Tongji University to check the calculation of bearing capacity. Through calculation and analysis, put forward to the original network frame the whole pre-stressing reinforcement and part of steel reinforcement bar outsourcing way, satisfying the requirements of design and specification, and to avoid the welding process, shorten the construction period, and achieved good social benefits.

The effects of pile diameter, the property of pile end bearing stratum, the material parameters of pile shaft and the changes of pile length on the bearing performance of extra-long and large-diameter single pile were examined with the finite element software ABAQUS to make the numerical simulation analysis, by establishing the overall axial symmetry model, which was based on the data of static load test of single pile at the Yellow River Bridge site. The results show that the ultimate bearing capacity of single pile, the stiffness and the end resistance ratio would increase gradually, whereas the compression settlement ratio decreases slowly; the pile end grouting can significantly increase the ultimate loads, and therefore, improve the bearing performance of piles, but it has little effect on the stiffness of pile when loading was smaller; the elastic modulus of pile shaft has no effect on the ultimate bearing capacity of friction piles, little on the end resistance ratio, while the pile compression settlement ratio would gradually decrease and the stiffness would increased with the increase of the elastic modulus of pile shaft, and this increase of stiffness would slow down with the increase of elastic modulus of pile shaft; it is unreasonable to improve the ultimate bearing capacity of extra-long single pile only by means of increasing the pile length.

The simulation of Profiled Steel Sheeting-concrete Composite Slabs is based on ABAQUS,the finite element simulation software.The simulation is compared with the test to verify correctness of the finite element simulation method.By changing shear connectors of composite slabs, studies are performed on the influence of shear-bond property ,the behavior of slip between sheeting and concrete,slip distribution along the composite slabs and so on.The results indicate that setting shear connectors ,such as shear reinforcement and studs, can improve ultimate bearing capacity and reduce the slippage between the interface.The studs’ effect is more obvious.Actual engineering should select suitable shear connectors,so that it can meet the strength requirement and be economical.

Four pairs of prefabricated reinforced concrete slabs were designed, cast, cured, assembled and test to investigate the flexural performance of prefabricated underground thin-wall box RC structure. One traditional integrated slab specimen with same size, material and reinforcement was also cast and test for comparison purpose. Four rebar constructional forms were conceived to compare the ability of transferring tension force between two slabs. Symmetric two-points monotonic static load test were performed to attain their flexural performance. The test results indicates: the prefabricated RC slab can provide better deformability and ductility, but the flexural bearing capacity is lower, comparing with cast-in-situ integrated RC slab; steel rebar form at seam have some effect on the flexural bearing capacity of prefabricated RC slab.

As an improvement form of deep foundation, belled steel’s engineering research and application has matured. On the basis of belled steel pile, a new form of steel piles, explosive expansion steel piles, is proposed. Based on ABAQUS, the two-dimensional axisymmetric finite element contact model of pile and soil is set up. The parameters include: the diameter of the expanding section and highness of the expanding section have been analyzed through the Q-S curve. The results show that: the vertical bearing capacity increases significantly with the increase of the diameter of the expanding section, but decreases with the increase of the highness of the expanding section

The method of calculating K-joint’s ultimate strength given by “Code for design of steel structures” GB 50017-2003 requires that, the angle θ between K-joint’s chord and brace is no less than 30°. While, due to the request of electric gap or transmission line corridor, the angle of steel tubular tower’ K-joint in power transmission line have to be designed less than 30° sometimes. In order to solve the engineer problem, rib stiffener were usually added to K-joint structure. 3 kinds of new rib stiffener to directly-welded K-joint of steel tubular tower were designed, and numerical simulation was made to study the structures’ performance under load and ultimate bearing capacity. With new-designed rib stiffener, K-joint’s stress distribution in weld jointing area, where usually bear stress badly, is improved obviously. Stress concentration is eliminated, and maximum stress is lowered. It is suggested that, in the case of exceeding code’s suggest range, k-joint structure must be reinforced to increase intensity, and the 3 format of rib stiffeners can improve the structure’s stress distribution and ensure the security of the structure.

Recently, polygon hole castellated steel beams have been studied and applied which had better social and economic benefits. But it brings more difficulties to extend castellated steel components that less studies of castellated bending members. In this essay, ANSYS that is a kind of finite element software had been used to analyze castellated bending members, and characteristics of stability bearing capacity in moment plane of regular hexagon hole castellated steel components had been studied that can provide references to engineering design.

The fire resistance ability of load-bearing column of building structure under fire is an important aspect affecting the safety of the structure. Although a large number of research results have been achieved in this respect, the researches on the numerical analysis of the bearing capacity and deformation process at high temperature are still not sufficient. The numerical simulation of the bearing capacity and deformation process at high temperature is hard to carry out and complex to operate, and not practical as well. Therefore, simplified analysis method is adopted to analyze the deformation and internal force of the controlling section of the load-bearing column subjected to fire. Besides, taking the concrete filled circular steel tubular column as example, the basic analysis theory of the fire resistance and the deformation performance of columns subjected to constant load is presented. The numerical calculation program which is developed on the basis of this theory can well simulate the process of deformation and the fire resistance of the columns subjected to fire. The simulation results are in good agreement with the experimental results.

ANSYS14.0 structural analysis software is used in order to make a ring rib-reticulated shell for the overall stability analysis. Considering the geometric nonlinear analysis and initial geometric imperfections influence , obtain a key node of the load - displacement curve and assess the ultimate strength of the structure. The results showed that: the structure meets the "Space grid rules" for monolayer shells stability requirements. And it is found that load distribution form and initial geometry defect has a great deal whit bearing capacity of single-layer lattice shell stability by comparison.

In order to study the performance of concrete frame columns that reinforcedby assembleinclined web steel truss, with the same reciprocatinghorizontal displacement and different axialcompression.It canbe calculate the mechanical behavior of concrete frame columns and reinforced columns by using the finite element analysis software ABAQUS. Simulation analysis shows that the bearing capacity ofreinforced columnshas greatly increased andpresented a full hysteresis curve. The result shows that the reinforcement method of assemble inclined web steel truss can greatly improve the bearing capacity and ductility of the concrete frame column, and the axial compression is larger, the better the reinforcement effect.

During the process of being used, engineering structures will undergo material aging and structural damage with time passing by under the combined influence of internal factors including load, environment and structural material[1], and accumulation of such damages will cause decrease of bearing capacity, durability and reliability. Among various factors influencing the reliability of in-service structures, ultimate bearing capacity plays the decisive role in safety. In this paper, the fourth-order moment of limit state function is inferred through calculation of failure probability of in-service structures, and thus safety and durability of in-service structures can be ensured.

The soft soil in Pearl River Delta regions is characterized with high water content, high compressibility and low bearing capacity. Therefore, when building the structures on such foundation, it’s necessary to pay attention to the deformation and stability. The projects' practice shows that, when analyzing the stability on foundation pit or slope with soft interlayer, it should not only calculate the overall stability of the slope, but also calculate the stability or bearing capacity of the foundation. Although sometimes the stability of the slope meets the requirements, it doesn’t means that the bearing capacity of the foundation meets the requirements because of the existence soft interlayer, the limitations of the circle slice method and the difference between the sliding surface and the actual sliding surface.

Bearing capacity tests of three reinforced concrete lining segments were carried out. The effect of the loading method and ultimate bearing capacity of the reinforced concrete lining segments and the maximum displacement and reinforcement ratio on the failure mechanism was analyzed based on the simulation results. The simulation results show that the yield load and ultimate load of the lining segments can be effectively increased because of the axial force effect. the loading method on the full surface was proposed. The the ultimate load and yielding load increase as the reinforcement ratio increase is radial distribution in the state.

In order to verify the feasibility of a new overallseismic reinforcement method of the framework. Firstly，carried low cyclic loading tests on reinforcedconcrete framework, then reinforced the framework with a new method, and repeatthe low cyclic loading tests , finally, compared and analyzed the data from twotests. Compared with the original framework, the shape of the hysteresis curveis more full and the skeleton curve of the parallel period is longer andthe ductility factor increased by 35% and the bearing capacity increased by 40%.The results show that reinforcement framework has better energy dissipationcapacity, ductility and transgender capacity.

According to the status quo detection of Wang Tong Gang Bridge, with the research of the reinforcement schemes, a reinforcement scheme of the bridge is put forward, through which the increasing bearing capacity of the bridge was tested.

The vertical bearing capacity calculation and security evaluation methods of high-pile pier skid-way quay while large offshore platform moving to barge whose deck elevation adjusted by aided jacks are researched by the theoretic analysis and numerical calculation method. Based on the study, the load effects of 6000ton skid-way quay are acquired under the offshore platform weight and jacks load caused in the process of large platform moving to the barge whose deck elevation adjusted by aided jacks, the security of skid-way is assessed, and the security measures of skid-way structure which should be taken during moving platform are proposed. The analysis of simulation results shows that the bearing capacity of skid-way in vertical meets the requirements of design under the jacks load and platform weight by using uniform pressure to compute. The 6000ton skid-way quay is secure while large offshore platform loaded to barge whose deck elevation adjusted by aided jacks. The conclusions above can provide the experience for the security evaluation of high-pile pier skid-way structure and the optimization of procedure to load the large offshore platform on barge whose deck elevation adjusted by aided jacks.