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Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to further study the shear behavior of reinforced concrete (RC) beams strengthened with ultra-high-performance concrete (UHPC) plates, an experimental study was carried out on three full scale RC beams, including a control one and two ones strengthened using UHPC plates with or without CFRP strips. The effects of UHPC plates and CFRP strips were focused. The test results show that the shear failure occurs in all the test beams, but the bearing capacity, stiffness and ductility of the reinforced beams are significantly improved. Among them, the cracking resistance of UHPC plates is improved by embedded CFRP strips, and the ultimate load and corresponding displacement are increased by 30. 8% and 28. 5%, respectively. The screw mechanical anchorage plays the role of lateral restraint and pin, which improves the contribution of UHPC plate to a certain extent. At the same time, a nonlinear finite element model is established to analyze the test beam. The simulation results are in good agreement with the test results, indicating that the constitutive relationship and related parameters selected in the model are reasonable and can be used to predict the whole process stress behavior of RC beams reinforced by UHPC plates. [ABSTRACT FROM AUTHOR]

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Rebar corrosion is the principal factor affecting the service performance of reinforced concrete (RC) structures. Corrosion reduces the effective area of rebars as well as performance, and weakens the pin bolt effect of rebar on concrete. In addition, when the rebar is severely rusted, the concrete cover breaks, and the bond behavior between reinforcement and concrete deteriorates, affecting the mechanical properties of RC structures. In this study, a three-dimensional numerical model for shear analysis incorporating the nonuniform corrosion of reinforcement was established using an RC beam as the research object. The effects of corrosion on the mechanical behavior of the RC beam were explored via a multistage analysis method (namely, corrosion-induced expansion stage and structural deterioration stage). To model and simulate the expansion of the corrosion products, nonuniform radial displacement was applied to the concrete surrounding the rebar. The cracking process and the damage patterns of concrete resulting from corrosion were obtained. Then, taking the corrosion state as the initial condition, the static load was applied to analyze the mechanical behavior of the RC beam. After verifying the rationality of the multistage numerical model, the effect of the corrosion of tensile reinforcement and the shear-span ratio on the shear behavior of concrete beams without web reinforcement was analyzed. The modeling analysis results show that the corrosion of longitudinal reinforcement causes obvious longitudinal corrosion fractures in the concrete beam. Moreover, with the development of corrosion, the cracking area of the protective layer increases, reducing the shear capacity of the beam significantly. Furthermore, the shear-span ratio has a larger effect on the shear capacity of noncorroded beams than that of corroded beams. Finally, based on the simulation results, the calculation formulas of shear capacity in relevant design codes were discussed, and a methodology for predicting the shear capacity of RC beams without web reinforcement was proposed.

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to investigate the shear behavior of reinforced concrete（RC） beams strengthened by ultra-high performance concrete（UHPC）, experimental investigations were conducted based on the studies of RC beams strengthened with different thicknesses of UHPC layers. The failure process and mode of the beams were observed during the test. The influence of UHPC on the bearing capacity and stiffness of RC beams was analyzed by analyzing the load-strain curve of test beams. In addition, contrastive analyses were carried out by using digital image correlation（DIC） method simulation to investigate the development of cracks. The results showed that the failure modes of strengthened beams changed from brittle shear failure to ductile flexural shear and flexural failure. The ductility and energy dissipation capacity of strengthened beams were improved. The cracking load, peak load and deformation capacity of the strengthened beams increased obviously with the increase in the thickness of UHPC layer. Through the DIC method, the micro deformation and strain distribution on the surface of the test beams were obtained, and the formation of cracks and failure modes can be further predicted. Finally, a calculation method to predict the shear capacity of RC beams strengthened by UHPC was established and validated by the test results. The calculation results were in good agreement with the test results. [ABSTRACT FROM AUTHOR]

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shenzhen University Science & Engineering is the property of Editorial Department of Journal of Shenzhen University Science & Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering Geology / Gongcheng Dizhi Xuebao is the property of Journal of Engineering Geology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of South China University of Technology (Natural Science Edition) is the property of South China University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Advanced Engineering Science / Gongcheng Kexue Yu Jishu is the property of Advanced Engineering Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Southeast University / Dongnan Daxue Xuebao is the property of Journal of Southeast University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To study the shear behavior of the interface of composite reinforced concrete walls with reinforcement truss, shear test on seven specimens with different parameters, including the roughness of interface, the quantity and diameter of the reinforcement truss, i. e. ， the reinforcement ratio for shear interface, were carried out. The failure phenomenon and mode, the shear force-interfacial slip relationship and the shear strength of the interface of composite reinforced concrete walls were analyzed. The results show that the shear capacity of the interface of composite reinforced concrete walls can be increased by making five gouges in the direction perpendicular to the shear force on both sides of the interface. When the depth of the gouges is 5 mm and 10 mm, the shear capacity can be increase by 26% and 3 2% respectively. It is also found that the shear capacity and the ratio of peak slip to crack slip of the composite interface can be increased by 5 7% and 930%，respectively, by increasing the shear reinforcement ration from 0 to 0. 241%. According to the shear force-slip model of the composite interface, a calculation formula was derived. The calculated value is in good agreement with the experimental value. The proposed formula thus provides a theoretical basis for the design of shear capacity of composite interface of composite reinforced concrete walls. [ABSTRACT FROM AUTHOR]

A total of six RC T-beam strengthened with near-surface mounted (NSM) BFRP bars and two control beams in shear were conducted lo investigate the effect of secondary loading on the shear behavior of the strengthened beam. The loading process, failure mode of the strengthened beams, load-deformation relationship, load-strain relationship, stress redistribution in inclined section. and the influence factors including initial load, the degree of unloading and embedded length at the end of BFRP bars were studied. The experimental results show that the shear failure of the strengthened beams is complicated and accompanied by secondary failure. When the diagonal crack appears and the stirrup yields, the stress redistribution in inclined section occurs. For the specimen subjected to secondary loading, the strain lag of BFRP bars is obvious, and the strain distribution of BFRP bars is uneven. The effect of the strain lag on the decrease of bearing capacity of the strengthened beam should be considered. The initial load, the magnitude of unloading and the appropriate embedded length at the end of BFRP bars in the flange are beneficial to improve the ultimate load and lo delay the crack development. The correlation coefficient should be introduced in the calculation of the shear bearing capacity of the strengthened beam and the requirements of construction details should be satisfied, which reflect the influence of these factors. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to explain the macro flexural behavior and shear behavior of concrete beams made with manufactured sand from the meso-index of manufactured sands, natural sand and three kinds of manufactured sands were selected in this research. The material indexes of gradation, fineness modulus, powder content, MB value and so on were compared. The digital image process method was used to obtain the shape parameters of different aggregates. The concrete workability, compressive strength and shrinkage were studied and compared through experiment. Finally, the flexural and shear beams were designed and the static tests were conducted to compare the cracking load, deflection curve and ultimate strength of the beams made with different kinds of sand aggregates. The results show that the shape parameters of ellipse ratio and circularity can be used to separate different kinds of aggregates. The strength and long-term dry shrinkage performance of manufactured sand concrete with reasonable gradation and shape parameter can reach or even exceed that of concrete made with natural sand. The failure patterns of the beams made of manufactured sands and natural sands are very similar for both flexural and shear failure mechanism. The bearing capacity of the beams made with manufactured sands exhibits a positive correlation with the concrete strength. The current concrete design method can well meet the engineering requirement. However, the concrete made with natural sand has a higher cracking load than the concrete made with manufactured sand. The current calculation method overestimates the cracking load of the concrete beam made with manufactured sand. Therefore, the cracking load of reinforced concrete beam made with manufactured sand obtained by current calculation method needs to be adjusted accordingly. [ABSTRACT FROM AUTHOR]

Corrosion of stirrups is always more severe than that of longitudinal steel bars, leading to possible shear failure instead of bending failure. This paper presents a study conducted by the authors on the effects of stirrup corrosion on the shear behavior of reinforced concrete beams. On this basis, the time-dependent behavior of RC beams in marine atmosphere was analyzed, and the degradation of bearing capacity and failure modes of the corroded beams were discussed. The influences of corrosion initiation time, stirrup diameter and concrete strength were also analyzed. The results show that with the increase of service time, the stirrups in the beam corrode before the longitudinal steel bars, which causes shear failure instead of bending failure. The degradation of structural behavior and the change of failure mode can be delayed by extending the corrosion initiation time, increasing the stirrup diameter and the concrete strength. [ABSTRACT FROM AUTHOR]

The welded reinforcement grid (WRG) is an alternative to conventional cross-and-tie reinforcement in concrete structures. However, the behavior of WRG as shear reinforcement in shear walls has not been thoroughly studied. The behavior of concrete shear walls reinforced with WRGs was examined through monotonic loading tests and quasi-static tests. Two specimens were subjected to monotonic loading and quasi-static loading. The WRGs were employed as horizontal distributed reinforcement. Two specimens were reinforced with an integral WRG, and the other two were reinforced with an overlapped WRG. The stiffness, shear capacity and failure mode as well as the development of strains in reinforcement were obtained and analyzed. The results indicate that the measured shear capacity of test specimens exceeded the value predicted by current Chinese code GB 50010—2010 ‘Code for design of concrete structures’. Compared with shear walls reinforced with traditional cross-and-tie reinforcement, WRG shear walls showed similar deformability. For specimens reinforced with overlapped WRGs, the shear capacity and the failure mode were similar to those of specimens reinforced with integral WRGs. The strain of horizontal distributed reinforcement at the position of overlap still attained its yield strain, which indicate that the capacity of reinforcement was fully exploited and the tensile force could be well transferred through the overlap zone. The RC shear walls reinforced with WRG showed a satisfactory shear capacity, which is similar to these with traditional cross-and-tie reinforcement. [ABSTRACT FROM AUTHOR]

To systematically study the shear behavior of shear wall with steel tube-confined high-strength concrete (STCHSC), unidirectional static loading tests were performed on 32 small-shear-span-ratio shear wall specimens with steel tube-confined high strength concrete, whose shear span ratios were 0.30, 0.56 and 0.80. The effects of shear span ratio, axial compression ratio, strength grade of outer concrete, section type, horizontal distributed steel ratio and vertical distributed steel ratio on bearing capacity, deformation capacity and failure pattern of the specimens were analyzed. Experimental results show that as composite component, STCHSC shear walls can transmit shear stresses between the surfaces of steel pipes and the outer concrete through ring bars welded to the surfaces of steel pipes. When shear forces don't reach the peak of bearing capacity, STCHSC shear walls can work well, having a high initial stiffness and high load capacity. For shear walls with shear span ratios of 0.56 and 0.80, the failure mode is diagonal compression failure. For shear walls with a shear span ratio of 0.30, the failure mode is featured by direct shear failure caused by inclined through-thickness cracks on outer concrete and the severe damages to concrete along horizontal reinforcing bars of the bottom wall region at the compression side. The failure process shows certain deformation capacity. Based on statistical analyses, shear capacity formula for STCHSC shear walls is proposed, exhibiting good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For reinforced concrete (R C) beams in corrosive environment, stirrups are more likely to corrode, and in severe cases, the corrosion may lead to the complete sectional-area loss at the corner. Due to the different sevice environment，uneven quanlity of concrete and different installation of the structure members, the fractured location of stirrups in reinforced concrete is irregular. By simulating the anchorage failure and bond loss of fractured stirrups， finiteelement analysis was carried out to investigate the effect of the spatial distribution of fractured stirrups on the shear performance of RC beams. Analytical output indicats that ： due to the anchorage failure near the bending end of stirrups, the fractured stirrups can not yield when the reinforced concrete beams failure. The shear capacity of reinforced concrete beams decreases with the number of yielded stirrups. About the effect of the positions of fractured stirrups induced by severe corrosion within the shear s p a n，c o m p a r e d with the positions located in the stirrups near the support points, the positions located in the stirrups near the loading points have a more significant impact on the shear performance of RC beams. When the fractured stirrups induced by severe corrosion take place both in the bottom corner of side-leg of stirrups near the support points and in the top corner of side-leg of stirrups near the loading points， the stirrups are nearly out of function，resulting in the lowest shear capacity，which is almost as the same as that of the specimens without stirrups. [ABSTRACT FROM AUTHOR]

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Beijing University of Technology is the property of Journal of Beijing University of Technology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Considering number and arrangement of anchor bolts and axial load level, four exposed steel column bases were chosen in a static horizontal reversed loading experimental research to study the shear behavior and shear mechanism. When the column base is loaded under pressure, the shear capacity of the base is provided by a static friction between it and the top surface of the foundation. The presence of moment at the column base could improve its shear capacity. When the column base is loaded under tension, the static friction between the base plate of the column base and the surface of the foundation is overcame, and the column base begins to slide and at this moment the anchor bolts begin to resist the horizontal force, but its effect is limited. The maximum flexural capacity of the column base is increased with more anchors bolts used. When the number of the anchor arranged is increased from four to six, the maximum flexural capacity of the column base is increased by 12% and the energy dissipation capacity is increased by 20%. When configuring the same number of anchor bolts, the hysteretic behavior is changed with anchor arrangements. When the anchor bolt is arranged along the outside of the loading direction, the bearing capacity of each anchor bolt is made of the best use. Therefore, in designing the exposed column base, the arrangement of the anchor bolts needs to be considered in order to make full use of anchor tensile behavior. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve the shear behavior and deformability of the steel reinforced short beams, four steel reinforced high ductile concrete (HDC) short beams and two HDC short beams were designed, and one steel reinforced concrete short beam and two reinforced concrete short beams were designed for comparison. The failure mode, shear capacity and deformability of the beams with different shear span ratios were studied by the static tests. The research shows that the shear behavior of short beams can be improved significantly by using HDC, which will achieve ductile shear failure mode and the steel reinforced HDC short beams, which fail in extrusion failure, have high shear capacity, good ductility and great integrity after failure. Comparing with steel reinforced concrete beam, the steel reinforced HDC beam shows lower damage and remain higher residual bearing capacity when it fails in shear-bonding failure. The equation for predicting the shear capacity of steel reinforced HDC beams has been proposed, which has good agreement with the test results. [ABSTRACT FROM AUTHOR]

Based on the static load tests of two reinforced concrete (RC) beams without fire, two RC beams after fire and four RC beams strengthened with CFRP sheet after fire, the effects of shear span ratio, CFRP sheet usage and flange on the strengthening shear behavior of RC beams after fire were analyzed. Using a self-developed finite element program, the average reduction coefficient of concrete tensile strength of beam section after fire and repaired with equal dimensions was calculated, and a practical calculation method for shear strength of RC beams strengthened with CFRP sheet after fire was proposed. The results show that rupture failure occurs in fully-wrapped CFRP sheet and debonding failure occurs in the U-wrapped CFRP sheet with additional anchoring. The shear strength of concrete rectangular beams firstly exposed to fire and then fully-wrapped with CFRP sheet is higher than, about 5. 3% -16. 6%, that of the unfired one. The shear strength of concrete T-shaped beams firstly exposed to fire and then U-wrapped CFRP sheet with additional anchoring is increased about 34. 0% compared with that of the corresponding unfired rectangular beam. The proposed formula for the shear strength of RC beams strengthened with CFRP sheet after fire has certain safety margin ratio, and can be used to calculate the strengthened shear performance of that member after fire. [ABSTRACT FROM AUTHOR]

Based on the concentrated load combined with fire effect by the ISO 834 time-temperature curve, the shear behaviors of six full-scale recycled concrete beams with different replacement ratios of recycled coarse aggregate were tested, and three other beams were tested at room temperature. Details were analyzed, which included failure modes, fire resistance limit, temperature distribution and deformation regulation, considering parameters such as the replacement ratio of recycled coarse aggregate and the initial load ratio. The finite element analysis models of the aforementioned six recycled concrete beams under fire were set up by ABAQUS, through which the thermal analysis and the nonlinear coupled thermal-mechanical analysis were conducted. Besides, the theoretical calculation method and design calculation formula on shear capacity of recycled concrete beams under fire were given. The results show that recycled concrete beams and normal concrete beams have similar failure modes under fire. However, the spalling of concrete on the surface of specimen is more distinct with the increase of replacement ratio of recycled coarse aggregate. The fire resistance limit of specimen is increased with the increase of replacement ratio of recycled coarse aggregate and decreased with the increase of initial load ratio. In addition, the impact of initial load ratio on the fire resistance limit of recycled concrete beams is less than that of normal concrete beams. The temperature of test points of core concrete and stirrups is decreased with the increase of replacement ratio of recycled coarse aggregate at the same time, which indicates that recycled concrete beams have better fire-resistant behavior than normal concrete beams. At the end of fire test, the growth rate of deflection is decreased with the increase of replacement ratio of recycled coarse aggregate, which demonstrates that recycled concrete beams have better ductility than normal concrete beams when the damage on inclined section occurs under fire. The finite element analysis results are in agreement with the test results. And the theoretical calculation method and design calculation formula presented in this article can meet requirements of test and engineering design respectively. [ABSTRACT FROM AUTHOR]

The article focuses on the study which examines the shear behavior of high strength concrete square columns retrofitted by four carbon fiber-reinforced plastics (CFRP) hybrid methods using low reversed cyclic loading test.

In order to study the mechanical performance, shear capacity, and the seismic performance of the high strength cold-formed thin-walled steel composite wall with the OSB board and the fiber cement board, 7 high strength cold-formed steel composite walls were tested under monotonic loading and low cyclic loading. The test results indicate that: the joint of wall sheetings is a weak link in the composite walls, and the composite wall with the wide and complete steel liner at horizontal joint has high shear capacity and lateral stiffness; the fiber cement board composite walls have low shear capacity, and the shear capacity under the monotonic loading conditions is higher about 8.79% to 12. 27% than that of low cyclic loading conditions. The shear capacity and shear stiffness of the two kinds of single-sided sheet wall is approximately equal to that of the double boards composite walls. The energy dissipation of all specimens are almost equivalent under low cyclic loading conditions. [ABSTRACT FROM AUTHOR]

In this paper, quasi-static tests on 4 connection specimens of reinforced concrete beam-composite column with openings on steel tube were introduced to study the mechanical performance of the core area. The test results showed that the force-displacement hysteretic loops of specimens were plump, and the elasto-plastic deformation capacity of specimens was large. The specimen which the longitudinal reinforcement ratio of beam and of column and the steel ratio of steel tube of column were about same as those of the actual high-rise building failed in bending of the RC beam, and the seismic design requirements of strong column, strong core and weak beam were accomplished. Strengthening the steel tube with openings by welding stiffeners around openings or by thickening the tube wall could improve the shear behavior of the core area effectively, and enhance the shear strength of the core area. [ABSTRACT FROM AUTHOR]

Based on the test results of 12 groups of perforated corrugated plate connectors with different parameters, the failure modes, characteristics of load-slip behavior, impact of constructional parameters on the bearing capacity, variation rule of transverse rebar strain, and the von Mises stress curve of the shear connectors were studied by monotonic shear loading test. It can be concluded that the load-slip curve of the corrugated perforated shear connectors can be approximately divided into no slip stage, the elastic stage, the plastic stage and the the failure stage. The height of wave and the strength of concrete have great influence on the bearing capacity, shearing stiffness and the characteristics of load-slip. The von Mises stress of the welding side is greater than that of free side. The von Mises stress of the flap segment is greater than that of fiat segment. The von Mises stress of the side with holes presents linearly increasing trend with the increasing load. For the specimens with the same parameters, the smaller the diameter of transverse rebars is, the larger the stress of the rebars is. The larger the height of wave is, the smaller the shear force of the transverse rebars is. Compared with perforated plate connectors, the shear capacity of perforated corrugated plate connectors without transverse rebars increases by 300%, and the shear capacity of perforated corrugated plate connectors of contain transverse rebars increases by 200%. [ABSTRACT FROM AUTHOR]

Concrete was used to simulate the real rock. The effects of bolt prestress on the shear behavior of jointed rock mass were studied with the approach of joints directly shearing in laboratory and situ. The results show that as the prestress improved, the initial shear stiffness of the rock mass is improved, playing an important role in inhibiting the early deformation of the surrounding rock and improving the performance of bolt supporting; As the prestress increased, the jointed rockmass presented phased characteristics, including three stages, such as rapidly increasing resistance, slowly increasing resistance and resistance reduction characteristics; Situ tests show that bolt resistance could be enhanced when the bolt prestress improved and highly-pre-stressed fully-encapsulated rock bolts achieved good results for jointed rock supporting. [ABSTRACT FROM AUTHOR]