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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 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 study the time-dependent seismic performance of bridge under near-field pulse-like ground motions, a conventional continuous bridge considering chloride attack was taken as an example. In order to consider the vary uncertainty factors in the model, Latin hypercube sampling method was adopted to establish time-dependent model samples at different times. Then the time-dependent seismic performance of the bridge from the aspects such as capacity, demand and collapsed in the earthquake were studied and evaluated with incremental dynamic analysis. The results show that the seismic demand of structure in near-field pulse-like pulse earthquake is obviously greater than that in far field earthquake. As the mechanical properties of reinforcement changed after corrosion due to chloride attack, the constraint ability of stirrup to core concrete is weakened and yield strength and ultimate tensile strain of longitudinal reinforcement are reduced, which led to decline of the deformation ability of pier. Compared with the uncertainty of ground motion, the uncertainty of model parameters has little influence on the mean value and discreteness of seismic demand. With the extension of service time and the increment of corrosion of the steel, the probability of collapse of bridge pier increases. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of High Pressure Physics is the property of Chinese Journal of High Pressure Physics 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 Chinese Journal of High Pressure Physics is the property of Chinese Journal of High Pressure Physics 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.)

The prediction of deformation capacity of reinforced concrete (RC) columns is the foundation to realize performance-based seismic design. This paper presented a critical review of flexural-shear failure of columns based on Chinese design codes. The empirical formulas of ultimate deformation of RC columns were discussed, and the deficiencies of parametric model were revealed. The failure mode of flexural-shear, shear behavior and P-Δ effect are the main reasons for the scattering of the prediction of ultimate displacement. The length of plastic hinge is not a specific statistical sample. The prediction of ultimate displacement on the basis of equivalent plastic hinges method shows large scatter. In order to reveal the real shear demand in RC columns subjected to seismic loadings, the interaction between shear and flexural behaviors in plastic hinge zone should be taken into consideration. However, the corresponding simplified methods need to be improved. An effective method to evaluate the effect of shear on the deformation performance of columns is not available. In the GB 50010—2010 ‘Code for design of concrete structures’, the correction of the shear capacity formula for seismic design can effectively avoid the shear failure of columns under large displacement reversals, but the safety margin is different under varying ductility levels of ultimate displacement. The scatter of the prediction of GB 50010—2010 is larger than that of the original formula. Shear demand of identical columns under different test setups is not same due to the variety of P-Δ effect. The influence of P-Δ effect on the ultimate deformation capacity of RC columns depends failure modes. Finally, according to the relevant research in ultimate deformation, it is suggested that Chinese building code should be supplemented with an empirical formula for lower limit value of ultimate displacement by regression methods to improve performance-based design methods. [ABSTRACT FROM AUTHOR]

The strut-and-tie model (STM) is widely used in the calculation of shear capacity of reinforced concrete deep beams. Based on a reliable shear test database of simply-supported and continuous deep reinforced concrete beams without stirrups, the STMs of ACI 318-14，EC2 and CSA A23.3-04 were evaluated. The results show that the STMs of ACI 318-14 and EC2 cannot accurately reflect the influence of shear span-to-depth ratio on the shear capacity of deep beams, and the STM in CSA A23. 3-04 significantly overestimates the shear capacity of continuous deep beams. Therefore, based on the test database, a modified strut efficiency coefficient considering shear span-to-depth ratio and concrete compressive strength was proposed for the struts without minimum web reinforcement. By comparing with the shear test results and other STMs, it is verified that the improved STM with the proposed strut efficiency coefficient can be applied to a wider range of shear span-to-depth ratio (≤ 2. 5), and can predict the shear capacity of deep beams with both lower coefficient of variance (0. 2 9) and higher safety margin (5. 4% unsafe predictions). [ABSTRACT FROM AUTHOR]

Reinforced concrete slab-column structure is a common architectural form with excellent economic and technical indicators. However, slab-column structure without shear reinforcements has low lateral stiffness and poor seismic performance compared with reinforced concrete frame, due to the force-transferring mechanism and punching shear of the slab-column connection. In the past decades, many research achievements about the seismic performance of slab-column structure have been made, but the research is still insufficient. The state-of-the-art on the seismic performance of slab-column structure and design method in terms of seismic experiment, nonlinear analysis of equivalent frame model and seismic evaluation is introduced in the paper. Meanwhile, the summary, generalization and comment for the achievement and design method is made to provide ideas for subsequent research. In subsequent research, mechanism of connection punching shear should be revealed. The punching shear criteria or formula should be obtained based on the mechanism and can be used in nonlinear analysis model. Seismic design procedures should be set up based on the data from the structural nonlinear analysis. [ABSTRACT FROM AUTHOR]

In order to study the impact resistance behavior of RC beams, a series of static loading tests and drop weight impact tests were carried out on hinged RC beams. Numerical simulations for the impact tests were carried out using LS-DYNA, and then extended parametric studies were conducted. The test results show that: the failure characteristics of the RC beam under impact loading and static loading conditions are evidently different. Under impact loading, local damage governed the impact resistance of the RC beams with increase in the impact velocity; the damage is also greatly accumulated under repeated impact loading. Under static loading, the RC beams sustain the external loading through large deformation as well as intensive and well-developed cracking. Both the test and simulation results show that: an increase of the longitudinal reinforcement in the tension zone of RC beam can directly improve the impact resistance of the RC beams when longitudinal reinforcement ratio is relatively low. However, with increase in the reinforcement ratio, the impact resistance of the RC beams is gradually governed by local failure. The numerical simulation results show that the relationship between the longitudinal reinforcement ratio and the critical energy dissipation of RC beam follows a parabolic trend. By comparing the static energy dissipation of RC beam and extended numerical results, it is suggested that 90% of the static energy dissipation capacity can be taken as the critical energy dissipation when evaluating the impact resistance of RC beams. [ABSTRACT FROM AUTHOR]

In order to investigate the influence of aggregate types on shear behavior of reinforced concrete (RC) beams without stirrups, 16 simply supported beams, which consist of 8 beams with normal concrete and 8 beams with lightweight concrete, were tested to shear failure under point load. Other main variables in the test were shear span-to-depth ratio and longitudinal reinforcement ratio. The development of cracks, failure pattern, diagonal cracking load, ultimate shear strength, beam deflection in the middle span, as well as relative displacements at crack surface of the specimens were observed and measured. By comparing and analyzing the test results, it is shown that the diagonal cracking load and ultimate shear strength of lightweight aggregate beams are smaller than those of normal beams, and the shear failure crack surfaces of lightweight aggregate beams are much smoother. The tested shear strength of lightweight aggregate beams was compared with the predictions of JGJ 12--2006, ACI 318-11, CSA 23.2-04 and EC 2. By combining the test results in this study and 126 beams collected from literatures, the shear strength equation of JGJ 12--2006 was evaluated. Finally, a new equation for shear strength of reinforced lightweight concrete beams without stirrups was proposed. [ABSTRACT FROM AUTHOR]

Although a test database has been created in 1985 and plays an important role in the revision process of the Chinese code GB 50010--2010，the number of members and the range of test parameters have certain limitations. The shear test database was considerably expanded by collecting and filtering the test results of simply-supported rectangular cross-section beams in literatures at home and abroad，which can be used for the rationality evaluation of shear design formula of reinforced concrete beams in the Chinese code GB 50010-2010. The statistical parameters of calculation model uncertainty were obtained，and the first order second moment method considering the probability distribution of basic variables was used for reliability analysis. The results show that when evaluating the shear capacity of reinforced concrete beams with stirrups subjected to uniform loads，the reliability index of calculation formula in the Chinese code GB 50010--2010 can meet the requirements of the Chinese code GB 50068--2001 well. However, for beams with stirrups under corcentrated loads，the fitting curve of calculation formula is no longer the lower enveloping curve for updated test data, which can' t meet the basic requirements of the Chinese code GB 50068--2001, and it is also significantly lower than the reliability index of bending capac.ty of normal section. The Chinese code GB 50010--2010 is suggested to check the reliability of bearing capacity of re: nforced concrete beams after updating test data. [ABSTRACT FROM AUTHOR]

Copyright of China Sciencepaper is the property of China Sciencepaper 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 evaluating the safety of code models for the shear strength of continuous deep flexural members，a shear tests database is built in this paper by collecting and filtering the test results in literatures and research reports. The strut-and-tie model (STM) adopted by the American code ACI 318-11 and the shear strength equation for deep flexural members in the Chinese code GB 50010~2010 are analyzed and evaluated based on the database. The results indicate that both of the codes overestimate the shear strength of continuous deep flexural members. For the Chinese code, by setting the upper and lower limits of the shear span-to-depth ratio A to 3. 00 and 0. 25 respectively, its equation can safely estimate the shear strength of continuous deep flexural members ； for STM in the American code，its safety is improved by modifying the effective coefficient of concrete in strut. [ABSTRACT FROM AUTHOR]

In this paper, static tests on the shear performance of 4 specimens of grouted rebar connections used for precast concrete shear wall structure were conducted. Existing methods for calculating the shear resistance of the precast connections were compared with the test results. Then finite element models of the test specimens were established using the commercial finite element packages Msc. Marc. Parametric analyses were conducted to study the effects of axial compression ratio，the number of the interface rebars and the roughness of the interface on the shear performance of the connections. It is shown that the failure initiates at the interface of the mortar and the concrete. The shear resistance of the interface is mainly attributed to the interface rebars after cracking and slipping of the interface. Satisfactory ductility is observed in the test. The failure mode of the specimen at the ultimate state is the splitting of the concrete in front of the inserting rebar. The shear resistance then drops with the spalling of the concrete. It is concluded that sufficient interface rebars be placed at the connection to prevent the failure of the connection before the failure of the precast element in the design practice. [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.)

Failure modes and the influences on shear performance are researched based on three groups of six reinforced concrete one-way slab-column connection test with stud strengthening. One group is different shear span ratios reinforced concrete one-way slab without shear studs，the other two groups are contrast specimens with different spacing and shear stud' s length. The main parameters are the spacing of shear studs, the height of shear studs and shear span ratio. Test results show that compared to the reinforced concrete one-way slab-column connection, the shear failure, failure modes of connections with shear studs are inside (S50-5 series specimens) and outside (S50-7 series specimens) shear studs. Using shear studs can improve effectively ductility of the slab-column connection, and change the failure mode from the pure shear failure to bending failure. The inclined destruction cracks located in the intersection with shear studs are more gently. From what has been discussed above the ultimate shear bearing capacity is improved obviously. Reinforcement effect is different because of the change of stud spacing and stud length, which is more significant to the relatively small shear span ratio reinforced concrete one-way slab. Based on the test results design suggestions are given to reinforced concrete plate with different shear span ratios. [ABSTRACT FROM AUTHOR]

Post-punching behavior of 12 slab-column connections with various longitudinal reinforcement ratios, shear-span ratios and the integrity reinforcement layout was studied and compared. Some solutions could be adopted to enhance the post-punching behavior of flat slabs and to avoid progressive collapse. The test results show that the post-punching bearing capacity provided by the longitudinal reinforcement is insignificant because of the anchorage invalidation at early stage. On the contrary, integrity reinforcements could carry loads by developing the vertical component of the tensile stress and moment accompanied by a significant deflection which plays a major role in the post-punching process as they are the only remaining link between the punching cone and the rest of the slab. The effect is significant as the shear-span ratio is increased. The resistance is governed either by the breakout of the concrete or the fracture of the integrity reinforcement. It is essential to provide sufficient integrity reinforcement, increase the strength of concrete and cover thickness to improve the post-punching bearing capacity. The test results on the punching and post-punching bearing capacity were compared with the predictions of the formulas proposed by codes of GB 50010-2010 and ACI 318-95,which had a relatively large errors. At last, the suggested formula and structural measures were proposed which could give some suggestions for the compilation of Chinese codes. [ABSTRACT FROM AUTHOR]