Existing design and evaluation formulas for shear behavior of corrugated steel webs are mainly based on analyses of simply-supported corrugated plates or corrugated steel webs in I-beams with specific flanges, which could not refeclt the influence of flange constraint on shear buckling. Elastic shear buckling is the important basis for shear behavior of corrugated steel webs. In this paper, the elastic shear buckling behavior of 9 groups of four-edge simply-supported corrugated plates and 63 groups of I-beams with corrugated steel webs were simulated by the finite element analysis software ANSYS, adopting the eigenvalue buckling analysis. The models were divided into 9 series according to the web profiles. Based on the parametric study of flange dimentions, flange restraint and its influence on elastic shear buckling stress of corrugated steel webs were explored. The coefficients to describe the flange constraint level and the embedding effect were proposed. The results showed that the flange restraint had embedding effect on elastic shear buckling of corrugated steel webs, thus the elastic shear buckling stress of the corrugated web in an I-beam was higher than that of a simply-supported corrugated plate.

As an attempt to improve the fatigue performance of orthotropic steel decks, hot rolled thickened U ribs are largely used for the first time in the cross-sea steel box girder bridge of Xiamen Second East Passage. To clarify the fatigue mechanism of the novel bridge deck with hot rolled thickened U ribs jointed to deck plates by double-side welding, local models of orthotropic steel deck are built using ANSYS. Fatigue performance assessment of orthotropic steel decks with hot rolled thickened U ribs and U ribs with the thickness of 8 mm is implemented by the structural hot spot stress approach, and the stress history, range and distribution of fatigue details under wheel loads are analyzed. The results indicate that the hot spot stress of fatigue details with hot rolled thickened U ribs shows the similar fluctuation to that with 8 mm U ribs.For the orthotropic steel deck with hot rolled thickened U ribs, the hot spot stress amplitudes at the weld toe of the deck plate at the U rib to deck and diaphragm joint and the U rib at the end of U rib to diaphragm joint are reduced by 19% and 20% respectively, and the stress concentration at the U rib to deck and diaphragm joint is alleviated.

For the deep-buried building, the steel reinforcement of the uplift pile is usually controlled by cracks. Because the maximum loading value of uplift static load test is not given clearly in the code, the value used by each designer is not the same in the engineering practice. If the static load test value used is large, the steel reinforcement of the pile will be too large, and if the static load test value used is small, the safety reserve of the pile uplift bearing capacity can not be guaranteed. Combined with past engineering practice,this paper presents several safe, reliable, economical and reasonable methods for steel reinforcement design and acceptance testing of uplift piles, and gives some suggestions for crack calculation of engineering piles under test load and ground water buoyancy in the current code.

The No.3 Building Project of Qingdao International Shimao Center has 3 underground floors and 48 overground floors. With a frame core-tube system, the structural height is 175.8 m. The plane of the tower is oval, the facade is shuttle shaped,and the changes of the plane and facade are complex. SATWE and MIDAS software were used to calculate the elastic responses under frequent earthquake, and the results showed that the period ratio, inter-storey drift ratio,and shear bearing capacity ratio all met the requirements of the specification. Meanwhile, time-history analysis was used to make a supplementary calculation of the structure under frequent earthquakes. The results showed that the average seismic wave spectrum met the requirements of the specification. The structure was able to maintain good lateral resistance and torsion resistance under wind load and frequent earthquakes. By using SAUSAGE to conduct dynamic elastoplastic analysis of the structure, the calculated inter-storey drift ratios met the specification limits.

Nondestructive testing technology of timber structure plays an important role in the preventive protection of ancient wood buildings and the intelligent operation and maintenance of modern timber structures. This paper classifies ten testing methods according to their basic principles, and introduces their application scope, research status and existing problems, including visual testing, stress wave, drilling resistance, and cutting-edge exploratory methods such as computer vision, piezoelectric sensing, Electromagnetic wave. Finally, the development trends of wood structure nondestructive testing are discussed.

The large-span steel-concrete transfer layer truss is a novel conversion form of high-rise building structure. Monitoring and analyzing the mechanical properties during construction is critical to the safety of high-rise buildings. Real-time monitoring and numerical simulation technology were used in combination to analyze the mechanical characteristics of the large-span steel-concrete transfer layer truss of high-rise building during construction stage. In terms of displacement and stress as indicators, the consistency between the real-time monitoring values and the numerical simulation results is assessed and verified. In addition,the mechanical properties of the novel large-span steel-concrete transfer layer truss were presented. The results show that during the construction process, the stress and displacement values in each structural member of the conversion layer truss captured by real-time monitoring and derived from the numerical simulation meet the requirements of the specification and have a great safety margin; the higher the construction floor level, the smaller the influence of the vertical load on the truss stress and displacement; during the scaffold dismantling stage, vertical deflection would occur in the transfering truss.The finite element method can be used to evaluate the mechanical properties of the new large-span steel-concrete conversion layer truss.

In this paper, the statistical characteristics of the global stability bearing capacity of cold-formed thin-wall steel members under axial compression are described quantitatively. Firstly, the yield strength and eccentricity are selected as basic random variables. Then their numerical characteristics and probability distributions are determined. Based on Perry formula, the transfer process of randomness is studied. Afterward, the numerical characteristics and probability distribution law of stability bearing capacity are given. The comparison between the analytical results with test results indicates that the statistical characteristics of the global stability bearing capacity can be predicted through the randomness propagation method.

The slotting treatment after bellows are blocked in the prestressed construction process of long-span bridges will greatly weaken the bridge panel section and affect the bearing capacity and service performance of the structure. This paper studies the reinforcement treatment of large span bridge after the bellow is clogged, and puts forward the reinforcement scheme of adding prestressed tendons on the top surface of the original bridge panel and replacing the cushion layer on the original roof with new reinforced concrete composite layer. With this reinforcement method, the calculation results show that the total thickness of the bridge deck and the load on the bridge deck do not increase. In addition, the re-stretched original prestressed tendons and supplementary prestressed tendons together ensure the crack resistance of the structure. The thickness of the structural layer of the bridge deck increases, which ensures and improves the load-bearing capacity of the structure. It can provide reference for the reinforcement treatment of the same type of engineering.

This paper proposes a novel tooth-U bar wet joint （TUWJ） to improve the connection performance and construction efficiency of a prefabricated bridge deck. The load transfer mechanism was analyzed in detail through nonlinear finite element models in terms of concrete strain, interfacial contact stress, U bar stress, etc. a Parametric investigation of the critical factors of flexural performance was further conducted. The results indicated that the failure process of the TUWJ experiences concrete cracking at the root of the tooth, progressive degradation of the interface, yielding of U bar, and eventual concrete crushing. The evolution of load-deflection behavior could be separated into three phases, namely the elastic, elastic-plastic, and yielding phases. The yielding of the U bar at the ultimate load demonstrated that reliable force transfer was achieved by the proposed joint. Compared to the model without teeth, the model with teeth showed a 30.1% increase in cracking load. Furthermore, the diameter of the U bar and the thickness of the bridge deck were found to significantly affect the flexural strength of TUWJ, while the joint length mainly affected the post-cracking stiffness and the ductility of TUWJ.

With the application of vector form intrinsic finite element method, it shows excellent prediction results for large deformation and non-continuous problems. Aiming at the near fault response of the main non-structural member-large suspended chandelier, which is not getting the attention it deserves. In this paper, the vector form intrinsic finite element method is used to analyze the influence of simulation parameters on the response of multi-mass large suspended chandelier under sudden loading. The effects of different sudden loading modes and damping ratios on the vibration of multi-mass large suspended chandelier are discussed. The results show that the loading mode affects trajectory of the structure, and the change of damping ratio affects the speed of the structure vibration to the equilibrium position. This research can provide a reference for practical design and application of multi-mass large suspended chandeliers.

To study the energy dissipation mechanism of frame braces-tube structure under rare earthquake, the elastic-plastic time history of frame braces-tube structure and frame-corewall structure are carried out. The differences of energy dissipation are observed. A comparison with frame braces-tube structure with BRB is complemented. It is found that： （1） The energy dissipation of frame-corewall structure depends on coupling beam, while frame braces-tube structure depends on braces yielding. But the energy dissipation capacity of braces is not fully used due to its high yield strength. （2） The energy dissipation mechanism of frame braces-tube structure is unchanged when the braces are replaced by equal section BRB. （3） The energy dissipation capacity of BRBs is increase, and other components are decreased when the cross-section area of BRB is reduced. Therefore, the ideal braces-tube structure had better to use BRB to replace steel braces partly or completely.

Shear head can improve the punching resistance of slab-column connections in reinforced concrete slab-column structures. Meanwhile, shear head can also enhance the flexural resistance in the negative moment zone of the slab-column connections. This leads to a conflict with the seismic design principle of “strong column-weak beam” if the enhance effect is not appropriately treated. In this regard, modification to the traditional design was proposed, i.e., optimizing the form of shear heads and arranging them to the plate bottom as close as possible. By doing this, the punching resistance was maintained and the enhance effect to the flexural resistance was limited. For quantitative analysis, ten typical slab-column connections were designed for underground garages considering the variable parameters of column space and soil thickness. Results found that the enhance effect to flexural resistance was significantly reduced to 17% compared with that of 40% according to traditional design. In addition, shear head can contribute to the direct shear resistance at “slab-column interface”. This was quantitatively demonstrated on the basis of ten slab-column connections.

In recent years, with the development of building industrialization, precast concrete shear wall has been widely used. To reduce the wet operation in the construction process and ensure the connection joint quality of precast concrete shear walls, a new bolted connection method for the precast concrete shear wall is proposed. In the core area of the shear wall, edge component, the design of the bolt number is based on the principle of equal strength replacement, the tensile strength of the bolt is much higher than the original steel bars. Then, according to the current national concrete design code, the bearing capacity of the bolt connected shear wall is calculated and compared with the finite element simulation results. It shows that The calculated value of normal section bearing capacity is consistent with the finite element simulation results; Through the calculation of shear capacity, it is concluded that the shear failure occurs in the wall with a low shear span ratio, which is compared with the damage cloud chart of concrete. The calculation of the shear capacity of the horizontal joint shows that the bolt connection has a great safety reserve in the horizontal direction, and there is no horizontal slip in the loading process.

At present, there are few experimental studies on the shear behavior of H-beam recycled aggregate concrete slab composite beams. The shear performance of five full-scale specimens of H-beam recycled aggregate concrete slab composite beams is tested. The size of each specimen is the same. The clear span is 3 000 mm, the model of H-shaped steel is HN200×200×6×6, the width of recycled aggregate concrete slab is 300 mm and the thickness is 100 mm. H-shaped steel and recycled aggregate concrete slab are connected by studs. The replacement rate of recycled coarse aggregate （RCA） is 0%, 50% and 100% respectively, and the design strength grade of concrete is C30 and C60 respectively. The shear performance of the specimens with different design parameters are compared and discussed, and the influence of design parameters on the shear performance of the specimens is analyzed. The results show that the structure of the composite beam with stud connection is reliable, and the H-shaped steel and recycled aggregate concrete slab have good joint performance. The shear performance and failure mode of composite beams with different replacement ratio of RCA are similar. The stiffness, shear capacity and deformability of specimens with high strength are improved.

This paper puts forward the assembled reinforced concrete shear wall-cantilever beam structure for half floor entry and the assembled reinforced concrete shear wall-special-shaped column frame structure for level entry, which can be widely used in adding elevator of existing residential buildings. The assembled structure and its standardized installation form are introduced. Through the analysis of the overall index of the structural model, the performance-based design of the normal section of the bottom grouted joint and the checking calculation of the shear strength of the horizontal grouted joint of the shear wall, the stiffness and bearing capacity of the structure are discussed in detail. The key technical points of the structure application are pointed out, and the standard design process is suggested.

After earthquakes, it is found that the coupling beams and the bottom corners of traditional shear wall structures easily suffer damage which is very difficult to be repaired, thus causing economic lost. To solve this problem, a type of shear wall structure with viscoelastic dampers as replaceable coupling beams was investigated. A case study of a 10-story coupled shear wall was carried out. Finite element software OpenSees was utilized to build a traditional structure and a structure with replaceable beams, and conduct elastoplastic time history analysis of both structures under four-level seismic fortifications. Then the seismic performance indexes such as inter-story drift ratio, story shear force, plastic damage of the coupling beams and the bottom corners of shear walls were compared and analyzed. The results show that compared with the traditional shear wall structures, the seismic performance of shear wall structures with viscoelastic dampers as replaceable coupling beams is improved because of smaller seismic response and less damage to the main structure．

The frame-eccentrical core tube structure is asymmetric in plane and may produce large adverse deformation in horizontal direction. The B3 model of concrete is used to analyze the construction of a frame-eccentrical core tube structure in ETABS. The structural horizontal deformation in different periods is calculated and the influence of horizontal deformation on the internal force of the structure is analyzed. The hoop effect of steel tube in CFST column, the stress redistribution between steel tube and concrete and the construction sequences are considered. The calculation results show that the horizontal deformation of the eccentric core-frame structure is large in the middle and small at both ends along the structural height. The results show that the horizontal deformation caused by creep and shrinkage increases obviously with time, and their amplitude will be larger than the elastic deformation in partial components in the later stage; besides, the results also show that reasonable planning for construction sequence can effectively alleviate the internal force of structural members. The accuracy of the model is verified by comparing with the measured data.

Deterioration of steel infrastructure due to service loads and environmental agents has been one of the major concerns in civil engineering community. Recently, iron based shape memory alloy （Fe-SMA） materials have been considered as an anlternative in retrofitting of aging steel structurs. Based on the shape memory effect, they can be conveniently used to apply prestress in comparison with traditional prstress techniques. This paper presents a state-of-art on fatigue strengthening of steel structures by using Fe-SMA materials, including the recovery stress of Fe-SMA materials, fatigue strengthening based on Fe-SMA materials, and effects of environmental temperatures and fatigue loading on the strengthening systems. The Fe-SMA retrofitting system is also compared with that by NiTinol-FRP hybrid materials.

The deviated pre-tensioned girder with discounted reinforcement avoids the shortcomings of post-tensioned prestressed concrete girder in tunnel construction technology and durability, and improves the mechanical adaptability of prestressed concrete structure, so it has a broad application prospect in bridge engineering. In practical engineering, the concept of load transverse distribution coefficient is often used to simplify the spatial multi-beam system into single beam system for analysis and calculation. However, with the increase of span, bridge width and the adjustment of beam spacing, this simplified calculation method will have a significant impact on the spatial stress state of the actual structure. Therefore, this article established the three-dimensional finite element model of I-beam, this paper studies force behavior of I-beam, through comparing all kinds of load transverse distribution coefficient calculation method and the error of the actual space force, put forward the reasonable and applicable method by studying the transverse beam spacing on force of main girder space, put forward reasonable design reference.

In order to study the seismic performance of steel frames with “HU” joints, a one-bay, two-story single-span steel frame with three different joints was designed, which were common bolt-welded mixed joint steel frame without cantilever beam OSF, OHF frame with cantilever beam, and HXF frame with “HU” joints. The finite element software ABAQUS was used to analyze the performance of three kinds of steel frames under quasi-static loading.In order to analyze the influence of P-Δ effect on the seismic performance of steel frames with “HU” joints, finite element simulations under five different loading conditions were carried out. The finite element analysis results show that the "HU" steel frames have fuller hysteresis curves, larger hysteresis loops area, better ductility, slower stiffness degradation and greater energy dissipation than other steel frames. Under the influence of P-Δ effect, the ultimate bearing capacity and energy dissipation capacity of steel frames with "HU" joints decreased significantly with the increase of vertical load at the column top. The P-Δ effect is more pronounced under the action of concentrated forces at the column top that match the actual working conditions. Beam loading has a great influence on ultimate bearing capacity and ductility of the steel frame with “HU” joints, which should not be ignored in design.

The pre-fabricated structure can improve construction efficiency and structural seismic and durability performance. At present, pre-fabricated structures have been used in domestic metro stations. The pre-embedded sleeve connection of the support and hanger can avoid problems caused by post anchoring such as damage to concrete and difficult control of anchoring quality, and its position error tolerant design is the key to the application of this technology. Therefore, this paper first proposed a structural form of bi-directional position error tolerant support connecting the pre-embedded sleeve and the lower vertical support hanger member. The support consists of a n-shaped plate connected with the pre-embedded sleeve and a top seat connected with the lower vertical member. Bi-directional position error tolerance can be achieved by setting long bolt holes in two directions in the support; Secondly, the finite element model with the given support mechanical parameter is established to analyze the stress distribution and deformation performance of the bearing under the design load, and the safety reserve of the support and the influence of the pre-embedded error of the sleeve on its deformation performance is studied;Finally,the bearing capacity and deformation performance of the support in three directions are studied through experiments, and the results show that the vertical connection bi-directional position error tolerant support of the pre-fabricated metro station supports and hangers proposed in this paper can meet the stress and deformation requirements of the design load, and has a good safety reserve.

The overall plan of the teaching area in Taicang campus of Xi'an Jiaotong-Liverpool University is a large ring connected with seven U-shaped buildings, with a diameter of 322 m and a perimeter of 1 000 m. The building has one underground floor and five floors above the ground. The maximum height of the structure is 23.51 m. There is a full-length roof frame above the ring, and the top elevation of the frame is 30.66 m. There are 7 structural joints and the whole building is divided into 9 independent structural units, including 3 double U-shaped buildings, 1 single U-shaped building, 3 connectors crossing the river, and 2 point shaped buildings in the ring. This paper compared the structural systems of different structural units, and discussed the key points and difficulties in project design. The design ideas and relevant conclusions can provide reference for similar projects.

The hydrodynamic added mass of the pier body has a great influence on the vibration characteristics and seismic dynamic response of high pier structures in deep water. To study the application scope of the hydrodynamic added mass calculation methods, a dynamic analysis model of circular high pier structure in deep water is established by using the finite element software ADINA, which is based on the fluid-solid coupling full numerical method of potential fluid element and the hydrodynamic added mass method based on Morison equation.By comparing and analyzing the vibration characteristics and seismic response of these two models, the accuracy and application scope of the hydrodynamic added mass model are discussed. The results show that the ratio of depth to width has a significant influence on the accuracy of vibration characteristics and seismic response of high pier structure in deep water calculated by the hydrodynamic added mass model, and reasonable control of the ratio of depth to width can ensure the accuracy of the hydrodynamic added mass model.

On Dec.22,2021, an earthquake with magnitude of 4.2 occurred in Changzhou, Jiangsu Province, which is sensible in Shanghai. The field-structure seismological array,which is recently established at different campuses of Tongji University, got the efficient acceleration signal of this earthquake. The peak ground and building acceleration of five stations are in the range of 1-5 cm/s² and 1-6 cm/s² respectively. By comparative analysis of the field and building signal in time and frequency domain, the peak ground acceleration, response spectrum of ground signal along with the dynamic characteristic of the building signal were studied. The influence of the earthquake on Shanghai is relative sensible to low buildings of short natural period. Rapid intensity assessment by field and structure signal is discussed and the intensity of different campus is 1 to 3.

The resource utilization of waste concrete and sintered bricks is an important way to solve the piling and pollution of urban construction waste. The effects of different fibers and fiber content on the mechanical performance of nano recycled concrete were analyzed through experimental research.The results show that the compressive strength of nano recycled concrete decreases with the incorporation of polyvinyl alcohol （PVA） fiber or polypropylene （PP） fiber, and PP fiber has a stronger weakening effect on the compressive strength; with the increase of PVA fiber content, the flexural strength and split tensile strength first increase and then decrease. When the content of PVA fibers is 0.9 kg/m?3;, the flexural strength and splitting tensile strength of nano recycled concrete are significantly improved. When the fiber content （1.2 kg/m?3;） is the same,PVA fiber has a better reinforcing effect than PP fiber. Fitting analysis of the strength index of PVA fiber nano recycled concrete shows that the splitting tensile strength and flexural strength have a good power function correlation with the compressive strength.

Steel pipe pile driven with resonance-free hydraulic vibratory hammer is popular in urban bridge engineering, which only requires potable equipment and shows a higher efficiency. For axial compression capacities of vibratory piles, comparison was made between those predicted by current Chinese codes. Field full scale tests were performed on two identical steel pipe piles with length of 50 m and outer diameter of 700 mm. Test results show that these codes overestimate the bearing capacity of vibratory pile tested at 42-day after end of driven （EOD）. After another 30 days （72-day after EOD）, measured capacity for the second test pile （virgin compression） increases not less than 16% compared the one measured at 42-day after EOD. The 72-day measured capacity meets the requirements of Specifications for Design of Foundation of Highway Bridge and Culvert and Shanghai Code for Investigation of Geotechnical Engineering. Load tests results show that, to achieve a higher measured capacity than current codes designed values, vibratory driven piles should be loaded no earlier than 42-day after EOD, which is larger than 28-day recommended by current codes. That is to say, vibratory driven piles need longer time for aging to produce a higher capacity. This also implies that capacity prediction methods given by current codes could be refined for vibratory driven piles. In Shanghai, for vibratory driven piles toed in dense sand, both Specifications for Design of Foundation of Highway Bridge and Shanghai Code for Investigation of Geotechnical Engineering produce well prediction.

In order to improve the failure pattern, prevent brittle failure, and improve bearing capacity of ordinary concrete beams, hybrid fiber reinforced cementitious composites （HyFRCC） with specific amount of polyvinyl alcohol （PVA） fiber and steel fiber was proposed to replace ordinary concrete. A total of 8 beam specimens were designed,including 6 PVA-steel HyFRCC beams with steel bars and 2 ordinary reinforced concrete beams. The shear and bending performance of the beam specimens were tested. The results of shear performance tests show that the failure pattern of the PVA-steel HyFRCC beams with steel bars is bending failure, while the failure pattern of ordinary reinforced concrete beam is shear compression failure. PVA-steel HyFRCC can change the failure pattern and effectively suppress the formation and development of shear cracks. The PVA-steel HyFRCC beams show ductile failure with multiple cracks. The shear span ratio has a great influence on the bearing capacity and failure pattern of PVA-steel HyFRCC beams with steel bars. And when the stirrup spacing decreases to a certain extent, the cracking load and the ultimate load of the test beams increase to a certain extent. The results of the flexural performance test show that all test beams suffer bending failure, and the bearing capacity and deformation capacity of the PVA-steel HyFRCC beams with steel bars are significantly improved comparing with ordinary reinforced concrete beams. Furthermore, numerical simulation of test beams was carried out based on the finite element analysis software ABAQUS by combining stress-strain relationship of PVA-steel HyFRCC with concrete damage plastic model. The numerical simulation results are in good agreement with the experimental results.

To investigate the performance of socket connections for precast columns subjected to axial load, through the nonlinear three-dimensional numerical approach, this paper introduced the details of the designed models and studied the effects of column embedment length, column surface texture, and grout strength on the connection performance. The results indicated that：the ABAQUS numerical model with the surface contact algorithm adequately captured the structural behavior of the socket connections;the specimen with round foundation and confining steel tubes was adequate to fully exercise the axial performance of socket connection; increasing of column embedment length increased the strength of the socket connection in a linear relationship, whereas it had negligible effect on the side shear stress of the socket connection; the socket connections with different column surface texture exhibited comparable axial performance; the connection strength was increased by only 11.4% with increasing the compressive strength of grout from 40 MPa to 80 MPa.

To study the influence of stiffness ratio on the performance of buckling-restrained brace-concrete frame structural systems and its likely reasonable value range, three concrete frames with different initial storey drifts are designed and analyzed respectively. By means of dynamic time history analysis of frequent earthquakes and rare earthquakes, the influences of different stiffness ratios on seismic performance of the frame structure, such as the inter-storey drift angle, inter-storey shear force, hysteretic energy dissipation ratio of bracing, plastic damage distribution, etc. Based on the analysis results, the likely suitable stiffness ratios are proposed for structures with different initial drift angles.

Structural damage detection is a hot spot in construction, machinery and other engineering fields. It is of great engineering significance to evaluate the structure through vibration signals, understand the current state of the structure, and provide reference basis for the operation and maintenance of the structure. The recurrence plots have the characteristic of being able to reflect the internal characteristics of the structure, and the Recurrence Quantification Analysis （RQA） method is often used to analyze the recurrence plots of the structure. This paper investigated the feasibility of the method in structural damage identification by using the experimental test of a five-story steel frame model.

The vector form intrinsic finite element method （VFIFE） is suitable for analyzing and simulating the large deformation, nonlinear or discontinuous mechanical behaviors of the flexible structures effectively, without assembling the global stiffness matrix. As for that, the modal parameters cannot be solved by eigenvalues directly. In this paper, referring to the stochastic subspace identification （SSI）, the covariance based stochastic subspace Identification program （VFIFE-SSI） is nested in the VFIFE solver. The modal analyses of the twin-cable network and the different cables network VFIFE models are carried out respectively, and the modal frequencies, damping ratios and mode shapes of the cable network are obtained. The accuracy of the VFIFE-SSI method is verified by comparing the results of the analytical solution with the traditional finite element analysis results. Meanwhile, the results show that the stiffness and damping coefficient of the cross-ties will influence the modal parameters of the cable network, and the overall performance of the cable network can be adjusted by varying the cross-tie parameters in engineering.

Due to the large difference of the cross-section dimensions in the two main axis direction, slenderness ratios of the flat column （which cross-sectional aspect ratio between 1 and 4） are correspondingly different. When the column height continues to increase, this gap will result in large difference in axial force effects. Considering the influence of different loading angles, axial force levels, eccentricity, cross-sectional aspect ratios and the nonlinear constitutive relationship of the material, the problem of the second-order effect of the flat column will become more complicated. Based on the eccentricity magnification coefficient η method of the one-direction eccentric compression, a large amount the samples with variable parameters and multi-levels was analyzed using OPENSEES, which was also calibrated with experiment result. Moreover, the above-mentioned influencing factor was quantified in the η formula by statistics fitting analysis. The obtained η formula can be used in the design of long flat columns subject to bidirectional eccentric compression.

Based on the theory of elastic mechanics and corrosion mechanism of reinforcing steel, the critical corrosion amount of reinforcing steel for cracking of concrete cover was derived. Based on Faraday’s law, an analytical model for time to corrosion-induced cover cracking in reinforced concrete structures was established. The proposed analytical model was verified by comparing the analytical predictions with the experimental results. The main factors affecting the time to corrosion-induced cracking were analyzed. The analytical results show that the time to corrosion-induced cracking increases gradually with the increase of thickness of concrete cover thickness and elastic modulus. The time to corrosion-induced cracking decreases gradually with the increase in the volume expansion ratio of corrosion products, corrosion rate and tensile strength of concrete.

To investigate the vibration characteristics of structures induced by pile driving, a field test is conducted and the frequency spectrum is studied. The dynamic response of the soil is predicted by using the finite element model and transient analysis, which is validated by combination of the measurement. The finite element model of the building and high-speed railway bridge is developed, and the influence of pile driving on structures is evaluated. The research shows that： （1） The frequency range of soil vibration induced by pile driving is from 3 to 30 Hz, with the peak frequency around 10 Hz. （2） The dynamic response of the soil at the location of the vibration source shows obvious pulse attenuation characteristics. The acceleration level of the soil attenuates rapidly with the increase of field test point. No obvious pulse attenuation behavior can be observed at the location of 60 m away from the vibration source. （3） The peak particle velocities at the foundation and top floor of the building are 2.7 mm/s and 6.6 mm/s, respectively. The maximum transverse amplitude and vertical acceleration at the mid-span of the high-speed railway bridge are 0.023 mm and 0.144 m/s², respectively, which are less than the limit value proposed in associated guidelines.

The existing researches on thread-fixed one-side bolted connections are simple, generally pure bending, pure tension, and pure shear. There is an obvious relationship between the bending and shear bearing capacity of the practical structural connections, so it is necessary to study the structural performance and calculation method of the connections under the combination of bending and shear. This paper conducted experimental research on the influence of bending moment and shear force on the mechanical performance of the thread-fixed one-side bolts bolted joints and traditional nut-fixed double-sides bolted connections for comparison. Parametric analysis of thread-fixed one-side bolts bolted joints under bending moment and shear force was carried out utilizing finite element model verified by the test results. The influence of shear force against bending performance was discussed, meanwhile, the interactive relationship between bending and shear capacity was drawn. The results show that the deformation of the screwed bolt hole caused by shear force will further weaken the anchor effect of the threads, and then reduce the tensile strength of the connection. Therefore, the shear force has a greater influence on the connection bearing capacity than the tensile force.

The spherical lobby area of Crowne Plaza Shanghai Dishui Lake adopts a single-layer spherical reticulated shell structure. In order to understand the seismic response of the single-layer reticulated shell under strong earthquakes, a finite element model of the single-layer reticulated shell under full-span live loads and half-span live loads is established by using Xue-Wierzbicki steel damage criterion and considering initial defects. The responses of multiple models under several groups of three-dimensional ground motions are analyzed. Damage development degree and failure mode of the single-layer spherical reticulated shell under different peak ground motions are studied. The conclusions are as follows. Under rare earthquakes, all members are in elastic state, and seismic performance of the structure meets the requirements. When the peak acceleration of local seismic wave is large, overall failure occurs in the reticulated shell, and the failure modes are different under the action of different seismic waves. When the stress of the latticed shell member is in the elastic or strengthening state, the influence of live load modes on its seismic response can be ignored. When some members of the reticulated shell enter the softening state and produce unrecoverable plastic deformation, there is a significant difference in vertical displacement of the top center point under different live load modes.

The project in the case is China's first monolithic precast concrete frame-corewall structure. The project is an AAA prefabricated building and a three-star green building. Through a pre-planning of prefabricated structural system selection and prefabricated scheme, combined with design, production,transportation and hoisting conditions, the structural design and splitting of prefabricated enclosure walls, fabricated floors,prefabricated core tubes and prefabricated concrete columns are planned.The logic of each planning is elaborated and the application of precast corewall technology is explored to provide a reference for the planning,structural design and splitting of similar prefabricated office buildings.It lays a foundation for the successful construction and standardized design of such projects,and promotes the development of concrete assembly technologies in the industrialization of new buildings in China.

Subway superstructure projects generally have the characteristics of limited site and strict foundation settlement control, which brings great challengers to structural design. What is more, in this project, large-span trusses are used to span the subway station, so the design of the pile foundation under the truss system is much more difficult because of the concentration of the load under the truss. To solve the problem that the pile spacing does not meet the code requirements due to the restricted site, this project adopts a new method to consider this adverse condition. The new method calculation results show that the shaft resistance bearing capacity of the pile foundation can still meet the design requirements after being reduced. The main reasons for the settlement of this project are analyzed. Based on the data such as the test pile results of similar projects, the settlement data is researched and estimated. Research shows that the main reason for the settlement of the cast-in-situ pile comes from the compression deformation of the pile body, the settlement of the pile foundation under the large-span truss is very small, which can meet the requirements of the subway settlement limitation. The number of piles under the truss is limited because of the restricted site, the horizontal bearing capacity of the pile foundation is insufficient, therefore, a horizontal force transfer plate is installed on the cap to solve the problem of the excessive horizontal force.

The Pi River steel truss aqueduct project is the first large steel truss aqueduct in China. Research on water filling process of this kind aqueduct is insufficient. Based on VOF （Volume of Fluid） and FEM （finite element method）, this paper conducts numerical simulation of the process of aqueduct water filling and the dynamic response of the structure during the process. Firstly, VOF method is used to simulate multiphase flow in the process of water filling at different gate opening heights, and then the results are transformed into two different load patterns： static load and dynamic load, which are applied to the structure to obtain the structural response. The results obtained by the two methods are compared.

The construction of regular subway station points is the first excavation of the main structure foundation pit,After the main structure is completed and capped, then the subsidiary structure foundation pit excavation, which will greatly lengthen the construction cycle, but also cause the main foundation pit part of the structure of the secondary excavation and secondary support cost increased. The soil layer of the Dianchi lacustrine sedimentary stratum is relatively special, which is soft soil with poor engineering properties and high sensitivity. To avoid excessive disturbance of surrounding soil caused by secondary excavation and save the construction period, the construction technology of simultaneous construction of main body and auxiliary structure foundation pit is explored. Based on Kunming Metro Wujiaba station project, the construction technology of excavation of main structure and auxiliary structure simultaneously in a lacustrine soft soil area. This construction method, construction procedure, construction technology, and measures to implement joint deformation after the seam displacement and seepage problems are studied, and combined with the monitoring data of the cause of the problems are analyzed, and targeted treatment measures were taken to ensure the safety of engineering, can be as the main body in the subway stations and affiliated construction provides a new technology measures, It also provides a reference for similar engineering analysis.