This article presents an experimental and numerical study on seismic performance of semi-tenon joints reinforced by steel angle in traditional timber buildings. Five specimens with two different reinforced connections and one unreinforced connection subjected to low-cyclic reversed loading on the bending moment are examined. The unreinforced connection consists of left and right beams inserted into the column that has been used in setting up the mortise before assembly. The first type of reinforced connection is formed by bottom steel angles bolted to the column and jointed to the beam by means of bolts. The second type of reinforced connection is made up of top and bottom steel angles bolted to the column and connected to the beam relying on vertical and transverse bolts. Moreover, two reinforcement techniques aimed at enhancing the seismic performance of semi-tenon joints are investigated, including the change of steel angle limb length and the variation of steel angle limb thickness. The test setup, joint connection, reinforced conditions, and material properties are introduced through detailed account of the experimental results and observations. The key behavioral patterns are identified from the experiments and the main response characteristics such as hysteresis, stiffness, flexural capacity, energy dissipation, and the failure mechanism. This article demonstrates that the steel angle can enhance the flexural capacity of the semi-tenon joints significantly. Besides, the use of greater limb thickness steel angle is shown to be an effective detail for adequately increasing the flexural capacity and rotation stiffness of the joints. Finite element simulations of experiments are also conducted, together with a detailed description of the modeling methods, so as to gain further insight into the influence of various factors on the behavior of joints.
Food security is a critical component of national security. Grain silos, as key infrastructure for food storage, must remain structurally resilient under seismic actions to ensure the stability of grain reserves. However, column-supported vertical-group silo structures are prone to spatial torsional effects during earthquakes due to eccentricities between the mass center and the stiffness center after grain loading, which can lead to serious structural damage or collapse. Based on this background, shaking table tests were conducted on a column-supported vertical-group silo structure as the research subject, with a scale ratio of 1/25 and in the 1 row × 3 column combination form. The dynamic response and spatial torsional effect of the structure under different grain storage conditions and seismic intensity effects were studied. To thoroughly analyze the factors influencing the spatial torsion in the structure, finite element–discrete element numerical analysis models of the structure were established based on experiments in Abaqus (6.14) software. The results indicate that in the column-supported vertical-group silo structure, the mass center of the group silo structure deviates from its center of rigidity after grain storage, resulting in significant and irregular spatial torsional effects under earthquake motion. The torsional displacement ratio and inter-story horizontal torsional angle of the structure gradually increased with an increase in the seismic intensity, reaching maximum values of 1.34 and 0.035 rad, respectively, when the peak acceleration input on the table was 0.4 g and under the full–full–empty storage condition. The effects of the void distribution, mass void ratio, and combination form of the group silo structure on the spatial torsional effect of the structure were studied to provide a scientific reference for the seismic design of column-supported silo structures for grain storage.
Multi-floored grain warehouses are widely used in China due to their efficient space utilization and high storage capacity. This study evaluates the seismic performance of such structures using a Composite Structure of Steel and Concrete (CSSC) system under various grain-loading conditions. A finite element model was developed in OpenSees based on actual loading scenarios, with both pushover and time history analyses conducted. Results show that the EEF condition (E = Empty, F = Full; top–middle–bottom = Empty–Empty–Full) leads to a 35.14% increase in peak base shear compared to the FEE condition (grain on the top floor only). Capacity spectrum analysis indicates that EEF provides higher initial stiffness and lower displacement across all performance points. Time history results reveal that configurations with lighter upper mass (EFF, EEE) are more prone to top-floor acceleration amplification, while FFF and FFE demonstrate more stable responses due to balanced mass distribution. The maximum inter-story drift consistently occurs at the second floor, with FFF and FFE showing the most significant deformation. All drift ratios meet code limits, confirming the safety and applicability of the CSSC system under various storage scenarios.
As an innovative structural system aligned with construction industrialization, prefabricated Steel-Reinforced Concrete (SRC) structures are characterized by high load-bearing capacity, efficient material utilization, and rapid construction. In this study, the mechanical behavior, failure mechanisms, and ductility characteristics of a prefabricated SRC multi-floored grain warehouse frame were investigated through quasi-static cyclic loading tests. To complement the experimental program, high-fidelity numerical models were developed using Abaqus, incorporating concrete plastic damage and steel material nonlinearity. The simulation results were rigorously validated against the experimental data. The findings indicate that the specimens exhibited typical shear failure modes with full hysteretic loops, demonstrating substantial energy dissipation capacity (equivalent viscous damping coefficient of 0.261). Notably, the results of the parametric study indicate that the integration of wall panels can significantly increase the load-bearing capacity and lateral stiffness of the frame system. The ductility of the samples was excellent, with displacement ductility coefficients ranging from 3.1 to 3.7. The ultimate inter-story drift angles at failure (1/49–1/38) substantially exceeded the code-specified limit (1/50), indicating robust collapse-prevention capacity. The numerical results strongly agreed with the experimental observations in terms of the hysteretic behavior, failure patterns, and skeleton curves, confirming the reliability of the modeling strategy for subsequent seismic performance analyses and parametric evaluations.