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Accelerated bridge construction (ABC) has attracted much attention in China as a new and efficient construction method. However, the seismic performance of the connections between precast piers and other structures limits the application of ABC in medium and high seismic zones. In this paper, a quasi-static test was conducted to investigate the seismic performance differences between a cap–column socket connection (PSC) specimen, which reinforced an embedded RC column-to-precast cap beam with a socket connection, and a cast-in-place (CIP) cap–column specimen. A fiber-based finite element model that considers bond slippage between the connection reinforcement and wet joint concrete is proposed. The numerical simulation results compared with the experimental results show an error of about 12% in peak bearing capacity and about 2% in initial stiffness. The experimental and numerical results show that the PSC specimen demonstrates comparable seismic performance to the CIP specimen. Experimental results verified that the finite element model in this paper is adequate to predict the seismic responses of a precast column with a reinforcement-embedded socket connection. A reinforcement-embedded RC column-to-precast cap beam with socket connection can be an effective solution for construction in medium and high seismic areas. [ABSTRACT FROM AUTHOR]

Based on the perspective of flight technology and flight safety, the unsaturated clayey foundation soil of a high plateau airport in the mountainous area of southwest China is taken as the research object, and the calculation method of the composite modulus of CFG pile composite foundation with the soil between the piles as the unsaturated soil is established according to the relevant characteristics of unsaturated soil, and the calculation method of the composite foundation's settlement is carried out on the basis of this method. At the same time, Plaxis finite element analysis software is used to model the actual project and numerically analyze the settlement characteristics of the composite foundation. Finally, the calculation results of the two methods are compared and studied with the actual settlement monitoring values on site. The study shows that: 1) the theoretical analysis method is able to consider the effects of pile length, pile modulus, and matrix suction in unsaturated soil of rigid piles on the composite modulus, which is more in line with the reality than the conventional composite modulus method that does not consider the unsaturated nature of the soil between the piles; 2) the resultant values computed by the theoretical and numerical analysis methods recommended in this paper are both smaller than those measured at the site but the difference is within the range of 10%, so that in the actual plateau of the High Plains airports can choose the two analysis methods recommended in this paper to conduct related research. [ABSTRACT FROM AUTHOR]

In this paper, a thorough investigation is presented on the static and dynamic behaviors of a short-span cable-stayed bridge (CSB) incorporating steel and carbon fiber reinforced polymer (CFRP) hybrid cables. The study focuses on the world's largest span and China's first highway, CFRP CSB. The performance of the CSB was compared using numerical simulations under four different cable patterns: steel cables, CFRP cables, and steel, and two types of hybrid cables with different structural arrangements. The results indicate that the use of the use of CFRP cables in the long cable region in the short-span CSB project investigated in this study offers improved performance in terms of stability, seismic response, and reduced displacements. In comparison to CFRP cables, hybrid cables have demonstrated a reduction of 12% in the maximum vertical displacement of the main girder. On the other hand, the hybrid cables result in reduced maximum internal forces and longitudinal and lateral displacements of the main girders and towers compared to steel cables. The difference in the arrangement of CFRP cables in the long cable region or short cable region is not obvious under dead loads, but significant differences still exist between the CFRP cable bridges in the short cable region and the long cable region in terms of live load effects, temperature effects, and dynamic characteristics. [ABSTRACT FROM AUTHOR]

Currently, in some domestic and foreign mines, the backfill drilling pipeline experiences a rupture phenomenon even when the wear degree is low. This results in a delay in production due to the filling becoming 'sick'. This paper presents, for the first time, the damage mechanism from a mechanical perspective and re-derives the anti-extrusion strength model of the backfill drilling pipeline. We investigate the influence of the law on the anti-extrusion strength of pipelines from the perspective of strata and cement rings. We then verify the theoretical and simulation results through engineering examples. The results demonstrate that the Mises stress criterion is a suitable modification principle for the anti-extrusion strength model of the backfill drilling pipeline. The anti-extrusion strength of the pipeline is related to the elastic modulus and Poisson's ratio of the stratum, and the thickness of the cement ring. It is negatively affected by the depth of the stratum. For hard strata, a cement ring with a smaller elastic modulus is suitable, while for soft stratum, a cement ring with a larger elastic modulus is recommended. When the missing angle of the cement ring is less than 60°, the stress concentration factor increases up to 2.2. The stress unloading capacity of the cement ring ranges from 32.7% to 37.8%, and optimal performance of the cement ring is achieved when it has high strength and low rigidity. The backfill filling pipeline of a copper mine abroad was destroyed due to external extrusion force exceeding its anti-extrusion strength value. The modified pipeline anti-extrusion strength model is 18.2% higher than the pipeline API strength value. This finding can inform the design of the backfill filling pipeline for China's kilometer-deep wells in the future. [ABSTRACT FROM AUTHOR]

As part of the ongoing China Fusion Engineering Test Reactor (CFETR) studies, this work focused on the study of the electromagnetic (EM) loads distribution on inboard (IB) and outboard (OB) blanket vertical segments. In this paper, a major central disruption scenario with a 36-ms linear current quench was performed in the ANSYS finite element software. EM forces and moments, both on the single module and the complete blanket segment, were calculated for the updated helium-cooled ceramic breeder (HCCB) blanket. Furthermore, the effect of EM loads with respect to poloidal segmentations on the back plate (BP) was studied. Results show that the EM forces and moments in the IB blanket barely changed, but in the OB blanket, great changes occurred. With poloidal segmentations increasing, EM forces loads on the BP will be reduced. This paper may provide important data to support subsequent optimization of the BP of CFETR and could also be a technical reference for other fusion organizations. [ABSTRACT FROM AUTHOR]

The assembled hollow-core slab bridge is the most widely used beam bridge in China. With the increasing traffic volume and traffic load in China, the joints of the hollow-core slab bridge are prone to damage. In this paper, a hollow-core slab bridge with locally curved prestressed tendons is proposed. Based on the static load test of a beam with joints taken from the cross section of a hollow-core slab bridge in practical engineering, a finite element nonlinear analysis is used to simulate the test, and the concrete and interface parameters under the correct analysis results are obtained. Finally, the parameters are applied to the three-beam and two-joint hollow-core slab bridge with a span of 10 m and a finite element analysis is carried out to explore the total failure process and performance improvement effect of the prestressed hollow-core slab bridge. The results show that the interface unit method can successfully simulate the new-to-old concrete interface where the joint is in contact with the precast beam segment. Compared with the static load test results, the analysis error of each finite element model is basically within 15%. Compared with the traditional hollow-core slab bridge, the cracking load, through-joint load, and ultimate load of the prestressed hollow-core slab bridge are increased by 50.0%, 91.7%, and 66.7%, respectively. Under the same load, the stress of the U-bar, the relative deflection of both sides of the joint, and the maximum width of the joint of the prestressed hollow-core slab bridge are lower than those of the traditional hollow-core slab bridge. When the ultimate load is reached, the longitudinal crack lengths of the traditional hollow-core slab bridge and the prestressed hollow-core slab bridge are 0.48 L and 0.4 L, respectively, and the damage degree of the prestressed hollow-core slab bridge is lower than that of the traditional hollow-core slab bridge. [ABSTRACT FROM AUTHOR]

An innovative foundation combining a bucket foundation and group piles (BGP) is proposed and investigated in this paper. Sleeve structures are added on the skirt of the mono-bucket, and piles can be inserted through the sleeves and connected with the bucket by grouting. With the same amount of steel, four finite element models of BGPs with different pile diameter and length combinations are established by ABAQUS, as well as a mono-bucket to study the unidirectional bearing capacity and failure mechanism. The results show that the bearing capacity of the BGP with suitable pile length and pile diameter is considerably higher than that of the mono-bucket foundation. Finally, static analysis and natural frequency analysis of the BGP are carried out based on the loading and geotechnical conditions at Yangjiang area of China. The results show that the BGP meet the design requirements, and the new BGP has engineering practicability. [ABSTRACT FROM AUTHOR]

The ?1100 kV UHVDC wall bushing is the important power equipment in the ?1100 kV DC power transmission project of China. However, the reported literatures rarely mention its design method and the optimization of its insulation structure. In this paper, two specific designing schemes including the resin impregnated paper (RIP) condenser and the metalshielded core have been both adopted in the design of the wall bushing. Moreover, the actual operating environment and the rated parameters of the ?1100 kV UHVDC wall bushing have been analyzed in detail. Then, the nonlinear finite element method (FEM) analysis has been applied in the three-dimensional electric stress simulation of the UHVDC wall bushing. The electric field and temperature dependencies of the composite insulation used in the wall bushing have been taken into account. The E-field simulation results indicate that with the RIP condenser, the potential and electric field distribution can be much more uniform along the composite insulator of the bushing. Therefore, the compact design of the wall bushing can be obtained by this designing scheme. On the other hand, with the type of the metal-shielded core, the high E-field strength areas are mainly concentrated on the metal shield and the outer grading ring of the wall bushing. Therefore, the nonlinear FEM was applied in the structure optimization of the internal metal-shielded system used in the wall bushing. Finally, the maximum E-field strength of the wall bushing can meet the control requirement. Based on the simulation results and the optimization structure, the ?660 kV scaled prototype of the UHVDC wall bushing has been produced and passed through all the type tests according to the IEC 62199. The feasibility of the design of the ?1100 kV UHVDC wall bushing has been verified. This paper can provide the theoretical guidelines for the design, manufacture and operation of the UHVDC wall bushing. [ABSTRACT FROM AUTHOR]

Frequency response analysis (FRA) is an effective approach for detecting mechanical damage in the windings of a transformer. However, the application of FRA to estimate the winding condition of autotransformers (ATs) employed in the China High-Speed Railway is problematic. Because the split windings of the ATs are connected inside the tank, it is impossible to measure the FRA curves for each split winding outside the tank directly. Therefore, it is difficult to identify fault winding and effectively diagnose the overall condition of the windings. This paper explores the features of FRA curves under different fault conditions to help distinguish the fault winding. An equivalent circuit model is built for the AT with split windings, and the electrical parameters of the windings are determined using the finite-element method. The model is then employed to simulate typical axial displacement faults. The results show that the first antiresonance and resonance of the frequency response for connections involving series windings or series and common windings may be visible features for diagnosing winding faults and the fault level. Specifically, the first and second resonances of the frequency response for the common winding connection may be regarded as the primary feature for identifying fault windings. [ABSTRACT FROM PUBLISHER]

Concrete-filled multicellular steel tube (CF-MCST) wall is widely used in China in recent years. In the companion paper, the moment capacity of the connection joining an I-beam to a CF-MCST wall was studied. Realizing that the insight into the connection's stiffness would greatly benefit performing a fine structural analysis, this paper aims to propose a theoretical approach for approximating the rotational stiffness of the connection. Finite Element (FE) model is first established for analysis, which is validated by using the experimental results extracted from previous studies. In order to attain the stiffness resulting from the endplate and the wall individually, an additional companion FE model is employed, where the endplate's deformation is negligible by using an extreme great value for the Young's modulus of the endplate and the connection's rotation is therefore mainly attributed to the wall's local deformation near the connection. For the stiffness accounting for the deformation of the endplate, the stiffness accounting for the local deformation of the wall, and the connection's stiffness, parametric study is then performed via the validated FE models whose geometrical parameters falling into the range conventionally taken in the engineering. Based on the FE analysis results, the abstracted mechanical model is proposed, resulting in semi-empirical formulas where partial parameters are identified by the means of regression analysis. It is found that enlarging the geometrical parameters would improve the connection's stiffness. Among the parameters, the beam height has the most significant effects on the connection's stiffness. Accordingly, increasing the beam height first is suggested for the aim of enhancing the connection's stiffness. The comparison of the results obtained via the FE analyses and that obtained via the proposed theoretical approach shows a good agreement, and the error is <10% regarding the connection's stiffness. [Display omitted] • Deposition of the stiffness of the connection of an I-beam to concrete-filled multicellular steel tube walls. • Estimating equations for the stiffness of the connection via abstracted theoretical model and regression analyses. • Predominant parameters identified through FE analyses of 300 connections. [ABSTRACT FROM AUTHOR]

For the last decades, fully erected container cranes have been delivered to a customer site by ships. On one hand, using this method of transportation is very attractive due to its cost and time savings. However, on the other hand, being exposed to cycling loads from the ship motions during the sea voyage, the crane structure accumulates fatigue damage. Using the accumulated fatigue damage parameter, the crane transportation could be associated with the amount of the working cycles the crane could have worked out during its normal operating at the customer site. In the presenting paper the research for the real case of a new crane voyage from China to Ukraine has been done. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate the effect of foraminoplasty using large-channel endoscopy during TESSYS on the biomechanics of the lumbar spine. Methods: A complete lumbar spine model, M1, was built using 3D finite elements, and models M2 and M3 were constructed to simulate the intraoperative removal of the superior articular process of L5 using a trephine saw with diameters of 5 mm and 8.5 mm, respectively, and applying normal physiological loads on the different models to simulate six working conditions—anterior flexion, posterior extension, left-right lateral bending, and left-right rotation—to investigate the displacement and facet joint stress change of the surgical segment, and the disc stress change of the surgical and adjacent segments. Results: Compared with the M1 model, the M2 and M3 models showed decreased stress at the L4-5 left FJ and a significant increase in stress at the right FJ in forward flexion. In the M2 and M3 models, the L4-5 FJ stresses were significantly greater in left lateral bending or left rotation than in right lateral bending or right rotation. The right FJ stress in M3 was greater during left rotation than that in M2, and that in M2 was greater than that in M1. The L4-5disc stress in the M3 model was greater during posterior extension than that in the M1 and M2 models. The L4-5disc stress in the M3 model was greater in the right rotation than in the M2 model, and that in the M2 model was greater than that in the M1 model. Conclusion: Foraminoplasty using large-channel endoscopy could increase the stress on the FJ and disc of the surgical segment, which suggested unnecessary and excessive resection should be avoided in PTED to minimize biomechanical disruption. [ABSTRACT FROM AUTHOR]

The autopsy and histopathologic examination are traditional and classic approaches in forensic pathology. In recent years, with the tremendous progresses of computer technology and medical imaging technology, the developed post-mortem computer tomography, post-mortem magnetic resonance imaging and other new methods provide non-invasive, intuitive, high-precision examining methods and research tools for the forensic pathology. As a result, the reconstruction of the injury as well as the analysis of injury mechanism has been essentially achieved. Such methods have become popular in the research field of forensic science and related work has also been carried out in China. This paper reviews the development and application of abovementioned post-mortem forensic imaging methods in China based on the relevant literature. [ABSTRACT FROM AUTHOR]

We examined the remains of an individual who was unearthed from the Tuchengzi site and was believed to be from the Warring States period in China. The remains exhibited segmental femoral fracture. We aimed to deduce the cause of fracture, medical interventions, healing process, and motion behavior after fracture healing using several techniques, including macroscopic observation, computed tomography (CT), and finite element analysis. Based on the morphology of the long bones, it appeared that the individual was male. The fractures resulted in an adduction angle of 5.47° and an anterior flexion angle of 21.34° in the proximal femur, while the femoral neck anteversion angle had been replaced by a retroversion angle of 10.74°. Additionally, the distal femur formed an abnormal anterior convex angle of 144.60°. CT revealed mature callus formation and visible trabecular bundles. The finite element analysis indicated that the maximum von Mises stress in the femur was 17.44 MPa during standing and 96.46 MPa during walking. We suggest that medical practitioners in the Warring States period possessed a good knowledge of thigh anatomy, enabling them to perform fracture reduction and fixation. Reasonable medical intervention facilitated fracture healing and load recovery. Satisfactory fracture healing ensured that the individual could engage in normal standing and walking activities after rehabilitation. [ABSTRACT FROM AUTHOR]

• At the steady state, the stress assessment of the reactor vessel in CiADS satisfies the requirements of ASME Code. • Adding a thermal insulation layer outside the reactor vessel may reduce the stress on vessel. • During the postulated ULOF accidents, the reactor vessel will not experience plastic deformation. • During the postulated UTOP accidents, the limit reactivity insertion to protect the reactor vessel from plastic deformation is 400 pcm. The China Initiative Accelerator Driven System (CiADS) was proposed by China Academy of Science since 2015. The subcritical reactor in CiADS is a liquid Lead Bismuth Eutectic (LBE) cooled fast reactor. When the reactor core is in operation, the LBE coolant will directly contact and corrode the inner surface of reactor vessel. Due to the high temperature, the corrosion will be more severe. If the stress on the reactor vessel exceeds the limit, the plastic deformation will occur, leading to the generation and expansion of defects and cracks, and the safety of the reactor will be affected. Therefore, evaluating the stress field of the reactor vessel under different operating conditions is a very important research project. In this paper, the finite element analysis software ADINA was applied to analyze the reactor vessel in CiADS, and the ASME Code was used as stress assessment standards. We can preliminarily prove that the stress assessments of the vessel during the postulated Unprotected Loss of Flow (ULOF) accidents satisfy the requirements of ASME Code. The limit reactivity insertion to protect the vessel from plastic deformation is 0.58$ in the postulated Unprotected Transient over Power (UTOP) accidents based on our current results. Therefore, we can preliminarily conclude that the current material selection and structural design of the reactor vessel in CiADS could survive most of the postulated transient accidents considering the stress effect. [ABSTRACT FROM AUTHOR]

Compared to the traditional two-column-bolt layout, the wide-type end-plate connections with four bolts in a row could resist a greater moment. In this paper, a detailed verified finite element model is employed to analyse the static behaviour of six wide-type end-plate connections, where parameters such as the end-plate thickness, bolt layout, extended or flushed end plate and the geometry of the stiffener are covered. The simulation results demonstrate that (1) in the elastic range, the transferred tension force of the bolts far from the beam web is about 0.33∼0.67 times that of the closer ones; (2) the shear force in the bolts is tiny; (3) at the ultimate state the bolts located far from the beam flange have a significant contribution to the loading capacity of the connection while it shows little contribution in the elastic state. In addition, a yield-line model of the tension part of the end plate is proposed. [ABSTRACT FROM PUBLISHER]

The retaining wall is a common slope protection structure. To tackle the current lack of sustainable and highly prefabricated retaining walls, an environmentally friendly prefabricated ecological grid retaining wall with high construction efficiency has been developed. Due to the asymmetrical condition of the project considered in this paper, the designed prefabricated ecological grid retaining wall was divided into the excavation section and the filling section. By utilizing the ABAQUS finite element software, the stress and deformation characteristics of the retaining wall columns, soil, anchor rods, and inclined shelves in an excavation section, and the force and deformation relationships of the columns, rivets, and inclined shelves in three working conditions in a filling section were studied. The study results imply that the anchor rods may affect the columns in the excavation section and the stress at the column back changes in an M-shape with height. Moreover, the peak appears at the contact point between the column and the anchor rod. The displacement of the column increases slowly along with the height, and the column rotates at its bottom. In the excavation section, the stress of the anchor rod undergoes a change at the junction of the structure. The inclined shelf is an open structure and is very different from the retaining plate structure of traditional pile-slab retaining walls. Its stress distribution follows a repeated U-shaped curve, which is inconsistent with the trend of the traditional soil arching effect between piles, which increases first and then decreases. For the retaining wall structure in the filling section, the numerical simulated vehicle load gives essentially consistent results with the effects of the equivalent filling on the concrete column. [ABSTRACT FROM AUTHOR]

The structural strain plays a significant role in structural condition assessment of in-service bridges in terms of structural bearing capacity, structural reliability level and entire safety redundancy. Therefore, it has been one of the most important parameters concerned by researchers and engineers engaged in structural health monitoring (SHM) practices. In this paper, an SHM system instrumented on the Jiubao Bridge located in Hangzhou, China is firstly introduced. This system involves nine subsystems and has been continuously operated for five years since 2012. As part of the SHM system, a total of 166 fiber Bragg grating (FBG) strain sensors are installed on the bridge to measure the dynamic strain responses of key structural components. Based on the strain monitoring data acquired in recent two years, the strain-based structural condition assessment of the Jiubao Bridge is carried out. The wavelet multi-resolution algorithm is applied to separate the temperature effect from the raw strain data. The obtained strain data under the normal traffic and wind condition and under the typhoon condition are examined for structural safety evaluation. The structural condition rating of the bridge in accordance with the AASHTO specification for condition evaluation and load and resistance factor rating of highway bridges is performed by use of the processed strain data in combination with finite element analysis. The analysis framework presented in this study can be used as a reference for facilitating the assessment, inspection and maintenance activities of in-service bridges instrumented with longterm SHM system. [ABSTRACT FROM AUTHOR]

Underground corrugated steel utility tunnel (UCSUT) is an optional alternative to traditional concrete utility tunnel. However, the structural mechanical behavior and surrounding soil arching state of UCSUT, as a typical flexible structure, depend on the soil-structure interaction between the structure body and surrounding soil, and are not clear currently. Thus, a case study on a real multi-compartment UCSUT project was reported in this paper. The field test and finite element simulation using ABAQUS software were conducted to investigate the mechanical behavior of the pipe-arched main compartment of the UCSUT. After that, the equilibrium equations were established based on the plane strain theoretical model to present the forces' balance of UCSUT and then an algorithm to convert the internal forces into external interface pressure was proposed. Based on the results from the field test and finite element simulation as well as the algorithm mentioned above, the soil arching state around the structure body was also analyzed. The results show that the UCSUT coordinates the external soil load through its own deformation, which in turn affects the surrounding soil arching state. After the soil covers the crown, the soil arching state outside the crown transitions from "negative" to "positive". The horizontal arching factor near the spring line always greater than the coefficient of earth pressure at-rest, showing a "passive arching state". In addition, the bending moment is closely related to the structural deformation as well, while the axial force is mainly affected by the cover height above the crown. • A case study on a real multi-compartment UCSUT project was reported. • The UCSUT has the largest span and largest length among UCSUT projects in China. • The equilibrium equations were established to present the forces' balance of UCSUT. • The UCSUT coordinates the external soil load through its own deformation. • The soil arching state outside the crown transitions from "negative" to "positive". [ABSTRACT FROM AUTHOR]

• The finite element analysis software ADINA is used to study the main reactor vessel in CiADS. • The maximum effective stress of all cases occurs at the weld of the cone and the cylinder on vessel. • The three areas bearing large stress are found and should be focused on in the subsequent engineering verification. • During the postulated ULOF accidents and UTOP accidents, the reactor vessel in CiADS will not experience plastic deformation. The China Initiative Accelerator Driven System (CiADS) was proposed by China Academy of Science since 2015. The reactor in CiADS is a subcritical fast neutron reactor cooled by a liquid lead–bismuth eutectic. The reactor operates at high temperature and bears high thermal stress. In addition to the heavy weight of the whole reactor, the vessel will bear large effective stress. If the effective stress exceeds the limit of the material, defects and cracks may occur on the main reactor vessel, which will affect the safety performances of the reactor. Therefore, it is very important to analyze the effective stress field of the reactor vessel. In this paper, the finite element analysis software ADINA was applied to analyze the reactor vessel in CiADS. We can preliminarily prove that the maximum effective stress that the vessel will bear during the postulated Unprotected Loss of Flow (ULOF) and Unprotected Transient over Power (UTOP) accidents is less than the yield strength of 316L stainless steel. Therefore, we can preliminarily conclude that the current material selection and structural design of the CiADS vessel could survive the postulated transient accidents considering the effective stress effect. [ABSTRACT FROM AUTHOR]

Summary: Modern traditional‐style steel (MTS) structure is an innovative architecture structure that is widely used in China. This paper explores the possibility of using viscous damper, which can be conveniently installed between beam and column, to replace "sparrow brace" at beam–column joints to improve its seismic capability. Three 1/2.6 scaled MTS double beam–column joints, one without viscous damper and two with viscous damper, were fabricated and tested under dynamic cyclic loading. The results indicated that the primary failure modes were cracking of base metal and local bucking at the beam ends. The hysteretic curve of specimens with viscous dampers was more plump than the common specimen without viscous dampers, indicating better energy dissipation capacity. The displacement ductility ratio was about 1.79–1.96, indicating the viscous damper has little effect on the ductility, whereas in plastic stage, the energy dissipation of specimens and viscous damper increased rapidly, indicating great energy dissipating function of viscous damper. Meanwhile, the results also proved that finite element analysis may stimulate and predict the mechanical behavior of MTS double beam joints with viscous dampers. [ABSTRACT FROM AUTHOR]

• Configuration of the composite column with angle steel was proposed. • FE model of the composite column was developed incorporating concrete confinement. • Arrangement of shear connector in column depends on the axial compression ratio. Steel-concrete composite high bridge pier has been applied increasingly in China and around the world. Most applied steel type in the composite piers are H-shaped steel and steel pipe, while seldom research or practice is associated with angle steel. This paper conducted parametric study on the composite column with equal-leg angle steel and aimed to investigate the ultimate load and displacement ductility of the composite columns with different parameters. The parameters include the type of shear connector (stud and perfobond connectors), the type of structural steel (H-shaped steel and angle steel), steel-plate hooping ratio, shear-span ratio, and axial compression ratio. Finite element analysis was conducted for each specimen, which incorporated the concrete confinement effect, as well as the inelastic behavior of concrete, structural steel, and longitudinal and transverse steel bars. The equal-leg angle steel composite column was found to have slightly higher strength and displacement ductility than H-shaped steel composite column. The increase of steel-plate hooping result in larger strength and displacement ductility for the composite column, and the increase of shear-span ratio and axial compression ratio decrease the displacement ductility. Research results suggest stud and perfobond shear connectors should be applied as axial compression ratio being larger than 0.2 and 0.3, respectively. This paper provides reference for research and engineering practice of the concrete encased angle steel composite columns and bridge piers. [ABSTRACT FROM AUTHOR]

This paper presents a theoretical investigation on the safety evaluation, stability evaluation, and service life prediction of concrete-filled steel tube (CFST) structures in a Northern China area with acid rain. The finite element software ABAQUS was used to establish a numerical model, which was used to simulate the axial compression behavior of CFST columns subjected to the combined actions of freeze–thaw cycles and acid rain corrosion. The model performance was validated using the experimental results of the evaluation of mechanical properties, including the failure mode and load–displacement curve. Then, the effects of the section size, material strength, steel ratio, and combined times on the residual capacity were studied. The results show that the section size has a smaller influence on the residual strength than the other parameters and can be neglected in the design procedure. However, the other parameters, including the material strength, steel ratio, and combined times have relatively large influences on the axial compressive performance of CFST stub columns subjected to a combination of freeze–thaw cycles and acid rain corrosion. Finally, design formulae for predicting the residual strength of CFST stub columns that are under axial compression and the combined effect of freeze–thaw cycles and acid rain corrosion are proposed, and their results agree well with the numerical results. [ABSTRACT FROM AUTHOR]

This paper takes the Taishan Nuclear Power Plant Project in Guangdong as the research background. The complicated entity finite element model was built with rational and simplified boundary conditions, and its mesh density was evaluated with the energy error over the model. The dome has a span of nearly 50 m with only 6 mm thick steel liner. The overlap element plus birth and death element technique was used according to the characteristics of time-varying structure in construction, and the effect of time-dependent elastic modulus of concrete was also taken into account ; the structural deformation and stresses of the large-span dome during continuous concreting construction were then analyzed. The structure stability bearing capacities at the critical stages of fresh concrete pouring construction were both analyzed which took into consideration the effect of initial geometrical imperfections and elasto-plasticity. The results show that the difference between the time-varying process analysis and the modeling analysis as a whole is significant, where the former structural deflection is 3.2 mm but the latter is 1.2 mm; the stability safety factor is not less than 3.4 and meets relevant requirement. [ABSTRACT FROM AUTHOR]

Abstract: Skewed bridges are widely used in China, with one prominent application being for high speed railways, and, as in other parts of the world, certain behavioral aspects need additional research to better understand their performance and to provide additional scientific basis for design. This paper summarizes results of a research project that encompassed 1:8 scale model testing and analyses of a three-span continuous, prestressed concrete (PC), box girder bridge having a 45° skew. The scale-model structure replicates an actual bridge being constructed for a high speed railway between Beijing and Shanghai. Research that is summarized here involved static and dynamic testing. Along with summarizing the design and construction details and the experimental procedure, experimentally obtained displacements and stresses, natural frequencies, mode shapes and damping ratios are presented and compared against those obtained from FE analyses of the tested structures. The influence of skew on the bridge’s static and dynamic behavior is also investigated. Research results provide important scientific basis for the design and construction of skewed bridges on high speed railways. [Copyright &y& Elsevier]

Abstract: According to the climatic characteristics in Tianjin where lies in the cold climate regions of China, the passage describes a technique called adjustable external blinds which is to enhance the architectural thermal comfort degree. This technique based on a series of experiments of architectures with different orientations in local climatic condition and numerical analysis of thermal environment with finite element method afterwards. This paper shows that alumina shutter has great advantages which can isolate indoor heat greatly in summer of Tianjin, and some optimization measures has also been adopted in order to improve indoor thermal comfort. [Copyright &y& Elsevier]

Abstract: The paper summarises research on high strength stainless steel tubular structures conducted at the University of Hong Kong, and the Hong Kong University of Science and Technology. Square and rectangular hollow sections were investigated. The test specimens were cold-rolled from high strength austenitic and duplex stainless steel sheets. The material properties of the test specimens were determined by tensile coupon tests at normal room and elevated temperatures. The initial geometric imperfection and residual stress of the specimens were measured. The experimental and numerical investigation focused on the design and behaviour of cold-formed high strength stainless steel structural members. The results were compared with design strengths calculated using the American, Australian/New Zealand and European specifications for cold-formed stainless steel structures. [Copyright &y& Elsevier]

Forensic biomechanics gradually has become a significant component of forensic science. Forensic biomechanics is evidence-based science that applies biomechanical principles and methods to forensic practice, which has constituted one of the most potential research areas. In this review, we introduce how finite element techniques can be used to simulate forensic cases, how injury criteria and injury scales can be used to describe injury severity, and how tests of postmortem human subjects and dummy can be used to provide essential validation data. This review also describes research progress and new applications of forensic biomechanics in China. The review shows the main research progress and new applications of forensic biomechanics in China. The review introduces eight cases about the application of forensic biomechanics, including the multiple rigid body reconstruction, the finite element applications, study of mechanical properties, traffic crash reconstruction based on multiple techniques and analysis of morphomechanical mechanism about blood dispersal. Though forensic biomechanics has a great advantage for the evaluation of injury mechanisms, it still has some uncertainties owing to the uniqueness of the human anatomy, the complexity of biological materials, and the uncertainty of injury-causing circumstances. [ABSTRACT FROM AUTHOR]

Until recently, ordinary concrete has been used to construct concrete-filled steel tube (CFST) arch bridges in China, which has resulted in the formation of circumferential gaps around steel–concrete interfaces. Furthermore, it has been found that harsh environments enlarge gaps, resulting in serious defects that decrease arch rib stiffness and even affect the dynamic features of the whole bridge. Hence, a finite element analysis and a reduced-scale model experiment were performed on a serviced CFST arch bridge rib member containing circumferential gaps to determine member tangent stiffness affected by the gap depth parameters under a small eccentric axial compression test. Next, tangent stiffness was applied to analyze the natural frequencies and modal vibrations of the whole bridge to study the influence of defects on bridge dynamic performance. A determination system was proposed for the effect of interface circumferential gaps on rib member stiffness and the dynamic features of the whole bridge. Therefore, this research provides a theoretical analysis method for CFST arch bridge maintenance and rehabilitation strategy. [ABSTRACT FROM AUTHOR]

With continued increasing construction of both electrified facilities and buried high‐strength pipelines in China, stray current corrosion defects have become an nonignorable threat for these pipelines. A comprehensive investigation on a new failure pressure prediction model for high‐strength pipes with stray current corrosion defects was conducted in this study. The mechanism of stray current corrosion in steel pipes was firstly elaborated in brief. After that, a parameterized finite element model for stress analysis of pipes with external corrosion defects was programmed by APDL code developed by general software ANSYS. By comparing numerical results with full‐scale experimental results, both the numerical model and the failure criteria for pipe burst were proven to be reasonable. Based on the finite element model, parametric analysis was performed using a calculation matrix set by orthogonal testing method to investigate the effects of three main dimensionless factors, that is, ratio of pipe diameter to wall thickness, nondimensional corrosion defect length, and nondimensional corrosion defect depth on pipe's failure pressure. Utilizing the parametric analysis results as database, a multilayer feed‐forward artificial neural network (ANN) was developed for failure pressure prediction. By comparison with experimental burst test results and results of previous failure pressure estimation model, the ANN model results were proven to have both high accuracy and efficiency, which could be referenced in residual strength or safety assessment of high‐strength pipes with corrosion defects. [ABSTRACT FROM AUTHOR]

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To probe into the time-dependent behaviour of the ballastless track–bridge structural system under train load, based on the import of the static and fatigue damage constitutive model of materials to simulate damage deterioration of the structural system and interface cohesive zone model to the interface layer, a three-dimensional nonlinear finite element model of the China Railway Track System Type II (CRTS II) ballastless track–bridge structural system was established using the equivalent static method. Then, using this model, we developed the numerical simulation analysis of the influence law of material damage deterioration on structural system performance under train load and revealed the fatigue evolution of the structural system. The results show that the beam remains in compressed status for the whole process, the track is in compression in the midspan and in tension at the beam end, and the tensile stress is larger near the shear groove under the double-track static load. Under the fatigue load, stiffness degradation of the structural system is not obvious, and integral rigidity of the structural system is dependent on the rigidity of the beam. Strength reduction of the materials caused stress redistribution of the structural system and had a larger effect on the stress of each layer of track structure than on the stress on the beam. The fatigue degradation of the cement-emulsified asphalt (CA) mortar layer material has a significant impact on the structural system, which directly affects structural layer stress variation with the fatigue loading cycle. [ABSTRACT FROM AUTHOR]

As China's infrastructure grows rapidly, the use of concrete-filled steel tubular structures for engineering applications is attracting increasing interest owing to their high section modulus, high strength and good seismic performance. However, for concrete-filled steel tubular members with large width-to-thickness ratio, steel tubes are prone to outward buckling when they are subjected to axial compression. Welding of longitudinal stiffeners on the steel tubes is one of the most efficient approaches for delaying local buckling and thus improving the mechanical performance of such type of concrete-filled steel tubular members. This study attempts to investigate the axial compression behaviour of concrete-filled stiffened steel tubular members with square sections through experimental study and finite element analysis. First, 14 concrete-filled steel tubular stub columns, with different width-to-thickness ratios of steel tube and depth-to-thickness ratios of stiffener, were subjected to axial compression loads and tested. It was found that the use of stiffeners increases the ultimate strength and improves the stability of the stub columns. Later, an investigation on the behaviour of the stiffened concrete-filled steel tubular stub columns was carried out through a three-dimensional finite element analysis. The accuracy of the finite element analysis model was verified by the test results. A parametric study was conducted to further evaluate the stiffening schemes that influence the axial compression strength. Finally, the research findings were synthesized into a new simplified model to predict the load-carrying capacity of stiffened concrete-filled steel tubular stub columns that allows for large width-to-thickness ratios. [ABSTRACT FROM AUTHOR]

Conclusions: The validated finite element model of human middle ear can be used as a tool in hearing loss research. Objective: To establish an accurate finite element model of the external ear canal and middle ear through micro-computer tomography and test its feasibility in the human. Methods: A fresh specimen of human temporal bone was scanned by micro-computer tomography. The finite element model was established based on the images, and then the simulation results were compared with published experimental data. Results: After a series of simulations were conducted, the simulated results were compatible with the published experimental data and this confirms the validation of the finite element model. [ABSTRACT FROM AUTHOR]

The bent sections from a main steam pipe in a thermal power plant in Shanghai were examined after 165,000 h service at 550 °C under 13.73 MPa pressure. The residual life of the bend sections is determined by evaluation of the service stresses and testing to obtain creep rupture data. Metallographic analysis and tensile, impact, and hardness tests are also conducted. These combined tests show that the properties of the steel deteriorated during service, displaying embrittlement tendencies; the corresponding microstructures exhibit grain boundary weakening and creep damage characteristics. However, considering no evidence of localized damage in the form of creep cavitation or surface cracks was observed in the examined parts, considering the residual life of the bends at service condition, they are adequate for an additional 44,000 h of operation. It is recommended that a health assessment should be taken after 25,000 h service exposure for safety reasons. [ABSTRACT FROM AUTHOR]