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To improve the bearing capacity and optimize the allocation of ring beam connection, a new type of steel reinforced engineered cementitious composite (ECC) ring beam connection linking the reinforced concrete (RC) beam and the concrete‐filled steel tube (CFST) column was presented. The superior tensile property of ECC can significantly solve the cracking problem that weakens the bearing capacity of the ring beam. In this paper, the failure mechanisms, contact press analysis and strain distribution of steel reinforcement for reinforced engineered cementitious composite (RECC) ring beam joints were analyzed by finite element analysis. Moreover, based on the ultimate equilibrium method, a comprehensive study was conducted on the stress transfer mechanism for the RECC ring beam joint. The bearing capacity model and simplified computational method for the beam‐to‐CFST column with RECC ring beam were proposed. Finally, the calculation method was demonstrated with experimental results. Comparison results showed good agreement, proving that the proposed bearing capacity calculation model had reliability and theoretical significance. [ABSTRACT FROM AUTHOR]

In this study, a ring light point cloud calibration technique based on collimated laser beams is developed, aiming to reduce errors caused by the position and attitude changes of traditional ring light measurement devices. This article details the generation mechanism of the ring beam and the principle of deep hole measurement. It introduces the collimated beam as a reference, building on traditional ring light measurement devices, to achieve the synchronous acquisition of the ring beam and collimated spot images by an industrial camera. The Steger algorithm is employed to accurately extract the coordinates of the point cloud contours of both the ring beam and the collimated spot. By analyzing the shape and position changes of the collimated spot contour, the spatial position and attitude of the measuring device are precisely determined. This technique is applied to the 3D reconstruction of the inner surface of deep holes, ensuring the accurate restoration of the spatial positional attitude of the ring beam by incorporating the spatial positional attitude parameters of the measuring device to precisely calibrate the cross-sectional point cloud coordinates. Experimental results with ring gauges and deep hole workpieces demonstrate that this technique effectively reduces the percentage of point cloud data outside the tolerance range, and improves the accuracy of the 3D reconstruction model by 6.287%, thereby verifying the accuracy and practicality of this technique. [ABSTRACT FROM AUTHOR]

Tube-gusset plate joints (TGPJs) play a significant role in tower structures. However, there is limited literature on calculation methods for the nonlinear stiffness and generic bearing capacity of these joints. To address this gap, this study employs full-scale tests, numerical simulations, and theoretical analyses to investigate TGPJs. The load transmission path and failure mechanism of the joint are elucidated by discretizing the joint chord. The joint primarily relies on the ring beam for load transmission until it reaches the limit state. After the ring beam loses its bearing capacity, the busbar beam continues to support the joint. A calculation model for the elastic stiffness and ultimate bearing capacity of the ring beam is formulated, considering the constraint effect of the busbar beam. Furthermore, the stiffness and limit state of multiple ring beams under cooperative loading are numerically analysed. The interaction mechanism of ring beams under cooperative loading is clarified, highlighting a decrease in stiffness and ultimate bearing capacity from the edge to the centre. The nonlinear stiffness and ultimate bearing capacity formulas for ring beams under cooperative loading are derived by fitting correction coefficients to the existing calculation method. Finally, an overall mechanical performance analysis model for TGPJs is established by incorporating a nonlinear stiffness spring support within the rigid beam spring support model. A comparison of the theoretical calculation results and numerical analysis values verifies the accuracy and feasibility of the proposed method for predicting the nonlinear stiffness of joints. [ABSTRACT FROM AUTHOR]

Ring beam is the main anchorage zone of the tendons in the nuclear power prestressed concrete containment vessel (PCCV). Its safety is crucial and has a great influence on the overall performance of PCCV. In this paper, two half-scale ring beams were tested to investigate the mechanical performance of the anchorage zone in the PCCV under multidirectional pressure. The effect of working condition with different tension sequences was investigated. Additionally, a half axisymmetric plane model of the containment was established by the finite element simulation to further predict the experimental responses and propose the local reinforcement design in the anchorage zone of the ring beam. The results showed that the ultimate load of the specimens under both working conditions was greater than the nominal ultimate tensile force. The original reinforcement design could meet the bearing capacity requirements, but there was still room for optimization. The ring beam was generally under pressure in the anchorage area, while the splitting force appeared in the under-anchor area, and the spalling force appeared in the corner area of the tooth block, which could be targeted for local strengthening design.

The microstructure and mechanical properties of adjustable-ring-mode (ARM) laser-welded, hot-stamped 22MnB5 steel joints were analyzed and compared with those of Al–Si coated 22MnB5. Al segregation into the fusion zone (FZ) was suppressed by a ring beam introduced via ring-beam-mode (RBM) and dual-beam-mode (DBM) laser welding. Dilution of the Al–Si coating in the FZ induced α-ferrite formation during hot stamping. After hot stamping, the α-ferrite fraction in the FZ decreased (from 23 vol% to 4.27 vol%) more than that in the center-beam-mode (CBM) welded joints owing to the ring beam. Electron backscattered diffraction analysis indicated the distribution of high-density and uniform geometrically necessary dislocations, which caused coordinated deformation in the martensite grains, in the RBM and DBM FZs. The average microhardness in the FZ in the tailor-welded blank (TWB) joints was ∼30–40 HV lower than that in the RBM and DBM welded base metal (480 HV) and that in the FZ of the CBM reduced to 295 HV because of the formation of a large amount of ductile α-ferrite. The tensile strength and elongation of the TWB joint in the CBM were ∼989 MPa and 1.1 %, respectively, which were significantly lower than those of the RBM (1245 MPa and 1.96 %, respectively) and DBM (1321 MPa and 2.12 %, respectively). Finally, the 22MnB5 steel sheets were subjected to ARM laser welding without removing the coating layer to evaluate the effect of the ring beam on Al segregation suppression in the FZ and mechanical properties of the TWB joints.

In this study, a ring light point cloud calibration technique based on collimated laser beams is developed, aiming to reduce errors caused by the position and attitude changes of traditional ring light measurement devices. This article details the generation mechanism of the ring beam and the principle of deep hole measurement. It introduces the collimated beam as a reference, building on traditional ring light measurement devices, to achieve the synchronous acquisition of the ring beam and collimated spot images by an industrial camera. The Steger algorithm is employed to accurately extract the coordinates of the point cloud contours of both the ring beam and the collimated spot. By analyzing the shape and position changes of the collimated spot contour, the spatial position and attitude of the measuring device are precisely determined. This technique is applied to the 3D reconstruction of the inner surface of deep holes, ensuring the accurate restoration of the spatial positional attitude of the ring beam by incorporating the spatial positional attitude parameters of the measuring device to precisely calibrate the cross-sectional point cloud coordinates. Experimental results with ring gauges and deep hole workpieces demonstrate that this technique effectively reduces the percentage of point cloud data outside the tolerance range, and improves the accuracy of the 3D reconstruction model by 6.287%, thereby verifying the accuracy and practicality of this technique.

• The intermediate stiffener plate failed due to local buckling under compressive loading when the joint reached its ultimate state. • The bolted connection regions constrained the local deformation of the ring-stiffener plates. • The larger the initial defect amplitude of a stiffener plate, the more significant its local buckling and the faster its stiffness decreased. • Theoretical results for ultimate bearing capacities of joints slightly higher than experimental results, max diff <10%. Tube-gusset (TG) joints that use stiffener plates as connecting plates for the crossarm chord are the main method for joining chords to tower bodies of transmission steel pipe towers. These joints experience the highest compression loads of the entire transmission tower structure. This study presents experimental research, numerical simulations, and theoretical analysis on the TG joint with a five-ring stiffener, where the middle stiffener plate serves as a connecting plate (referred to as C-Stiffener). This study elucidates the failure mechanism and mechanical characteristics of the C-Stiffener, identifies the key factors influencing its local buckling under compression, and proposes a stiffness calculation method for this type of stiffener plate. A calculation approach for the ultimate bearing capacity of the C-Stiffener is established by utilising its stiffness-deformation curve and a calculation method for the ultimate bearing capacity of the five-ring-stiffened TG joint under axial compression loading is proposed. The findings of this study can provide guidance for the meticulous design of joints between the crossarms and bodies of steel pipe transmission towers, thereby ensuring the safety and stability of transmission lines. [ABSTRACT FROM AUTHOR]

The solar wind particles reflected by the lunar magnetic field are the major energy source of electromagnetic wave activities, such as the 100 s magnetohydrodynamic waves and the 1 Hz whistler‐mode waves generated by protons and the non‐monochromatic whistler‐mode waves generated by mirror‐reflected electrons. Kaguya found a new type of whistler‐mode waves at 100 km altitude above the polar regions of the Moon with a broad frequency range of 1–16 Hz. The waves appear diffuse in both the time and frequency domains, and their occurrence is less sensitive to the magnetic connection to the lunar surface. The polarization is right‐handed with respect to the background magnetic field, and the wave number vector is nearly parallel to the magnetic field perpendicular to the solar wind flow. The diffuse waves are thought to be generated by the solar wind ions reflected by the lunar magnetic field through cyclotron resonance. The resonant ions are expected to have a velocity component parallel to the magnetic field larger than the solar wind bulk speed; however, such ions were not always simultaneously detected by Kaguya. The waves may have been generated above the dayside of the Moon and then propagated along the magnetic field being convected by the solar wind to reach the polar regions to be detected by Kaguya. Plain Language Summary: Unlike Earth, the Moon is not shielded by a global magnetic field; hence, solar wind particles can access the lunar surface. Although most of these particles are absorbed by the surface, a small fraction is scattered by the surface or reflected by intense lunar magnetic fields (magnetic anomalies) back into the solar wind and can become an energy source of wave activities. The protons reflected by these magnetic anomalies generate 0.01 Hz ultra‐low frequency waves and 1 Hz electron cyclotron waves. The electrons reflected by the lunar magnetic field form a field‐aligned beam that generates broadband electromagnetic waves, whose detection depends on the magnetic connection of spacecraft to the lunar surface. Kaguya found a new type of electromagnetic waves with a broad frequency range like the waves generated by the electrons, but less sensitive to the magnetic connection like the waves generated by the reflected protons. These electromagnetic waves are preferentially observed above the polar region of the Moon, not above intense magnetic anomalies. They are thought to be generated by the solar wind ions reflected by the lunar magnetic fields and propagate along the solar wind magnetic field to the polar region being convected down the solar wind flow. Key Points: Diffuse emission of whistler‐mode waves from 1 to 16 Hz is found over the polar regions of the Moon in the solar windRight‐hand polarized waves propagate parallel to the background magnetic field without a significant Doppler shiftThe waves are thought to be generated by the ions reflected by the Moon and propagate along field lines convected by the solar wind [ABSTRACT FROM AUTHOR]

This paper presents an experimental study on bearing capacity of polyvinyl chloride (PVC) carbon fiber-reinforced polymer (CFRP) confined reinforced concrete columns with ring beam joint (PCRBJs) under axial load. All PCRBJs conform to the principle of "strong-column/weak-joint". Four parameters including stirrup ratio, reinforcement ratio, height, and width of the ring beam are considered. Test results demonstrate that the ultimate bearing capacity of PCRBJs increases with stirrup ratio, reinforcement ratio, or ring beam width increases, while it decreases as ring beam height increases. On the basis of the local compression theory, as well as in accordance with confined concrete theory, the concept of gradual superposition of the confinement of multiple annular steel bars on core concrete is adopted, an effect coeffi- cient of joint height is introduced, and a model for predicting the ultimate bearing capacity of PCRBJs is proposed. The predicted results agree well with test data. [ABSTRACT FROM AUTHOR]

In this paper, seven specimens were designed to study the influence of the height (h), width (b), and reinforcement ratio (ρ) of ring beam on the failure mode, bearing capacity, deformation, and equivalent stress–strain relation of joint core reinforced with ring beam for connection of polyvinyl chloride fiber‐reinforced polymer confined concrete column and reinforced concrete beam. The experimental results indicated that the crushing of concrete in the joint core dominated the failure of specimens. The ultimate, yield bearing capacity and axial strain decreased with the increase of height, while raised with the improvement of width or reinforcement ratio. The growth of the strains of reinforcement and concrete accelerated with the increment of height, while decelerated with the rise of width or reinforcement ratio. Subsequently, based on the local compression theory, confined concrete theory, and the principle of superposition of multiple confinement, considering the influence coefficient of joint height βh and the enhancement coefficient of stirrups αs, a new formula was proposed to estimate the ultimate bearing capacity of specimens under axial local compression. Then, on the basis of Mander's model, taking the correction parameter η into consideration, a new model of equivalent stress–strain relationship was established. Verification results showed that the models proposed in this research agreed well with the experimental results. [ABSTRACT FROM AUTHOR]

This paper deals with the structural behaviour and the damage assessment of Italian "modern" masonry buildings during seismic events. "Modern" masonry buildings are characterized by a box-like structural behaviour, due to the presence of effective connections between horizontal floors and vertical load-bearing walls, which prevents local mechanisms such as the overturning of external façades during earthquakes. "Modern" masonry buildings were built in Italy since the first decades of XX century in those regions classified as seismic zone and since 1937 in the whole country, following the Italian code prescriptions that implicitly interdicted the erection of "ancient" masonry buildings. Starting from an in deep historical analysis of the Italian seismic codes' prescriptions for the design of "modern" masonry buildings, the typical characteristics of the most frequent structural typologies of unreinforced masonry buildings are outlined. Then, the typical damage mechanisms observed in "modern" masonry buildings damaged after the L'Aquila earthquake (2009) are reported in relation with both the global and local behaviour of the whole building and its structural elements. The analysis demonstrated that "modern" masonry buildings experienced a good box-like seismic performance, which avoided global or local collapses, but shown severe damage to piers and spandrels related to their reduced in-plane shear capacity. Given the lack of data on such kind of structural typology, this study is fundamental for understanding and modelling the seismic behaviour of "modern" masonry buildings designed before '80s according to different seismic design prescriptions and for defining effective strengthening solutions for reducing their seismic vulnerability. [ABSTRACT FROM AUTHOR]

There are many applications in electron microscopy, electron spectroscopy, as well as accelerator physics that require the combination of minimizing a focused electron beam's probe size while maximizing its beam current. This paper describes how this can be done through the use of annular focused electron beam column designs, where an electron beam is propagated and focused in the form of a ring beam. For probe semi-angles of π / 4 radians, a column consisting of two identical electric sectors and two identical focusing lenses functioning with odd symmetry will be presented, together with a wide-angle cold field emission gun design. The column is designed to cancel energy dispersion while limiting geometric aberrations to the third order at the point of final focus. This design is predicted to have over two orders of magnitude higher beam current than the corresponding conventional on-axis focused electron beam columns for the same final probe size. For a 1.2 keV annular electron beam, simulation results predict a spot radius of 4.8 nm at a working distance of 3.4 mm, final beam angle of 4 5 ∘ ± 2  mrad, and energy spread of ± 0. 1 5  eV. [ABSTRACT FROM AUTHOR]

This paper presents an experimental and numerical study on different retrofit solutions for stone masonry buildings with timber diaphragms in earthquake-prone regions, aiming at enhancing wall-to-diaphragm connections, diaphragms’ stiffness, and masonry properties. The experimental results of incremental dynamic shake-table tests on three full-scale two-story buildings, complemented by material and component characterization tests, are initially summarized. The first building specimen was unstrengthened. The second one was retrofitted at the floor and roof levels with improved wall-to-diaphragm connections and a moderate increase in diaphragm stiffness. Connections were also improved in the third specimen together with a significant enhancement of diaphragm stiffness. The calibration of two numerical models, versus the experimental response of the retrofitted building specimens, is then presented. The models were further modified and reanalyzed to assess the effects of masonry mechanical upgrades, which could be achieved in practice through deep joint repointing or various types of jacketing. These solutions were simulated by applying correction coefficients to the masonry mechanical properties, as suggested by the Italian building code. The effectiveness of the experimentally implemented and numerically simulated interventions are discussed in terms of strength enhancement and failure modes.

An axisymmetric BNEF method was proposed to analyze circular excavations. The governing equations of embedded cylindrical diaphragm walls were derived from thin-shell theory. A hyperbolic model was proposed to account for soil-structure interactions. Then, a FEM program was coded and verified using a case study. Overall, the method caught the main trend in the measured results and provided a reasonable estimation for engineering practice. Furthermore, the development of earth pressure and the hoop stress in the walls (ring beams) can be obtained using conventional parameters, extending the ability of the classic BEF method to aid the design of circular excavations. [ABSTRACT FROM AUTHOR]

This paper investigates the axial compressive behavior of a through-beam connection between concrete-filled steel tubular (CFST) columns and reinforced concrete (RC) beams. In this connection system, the steel tube is completely curtailed at the corresponding beam location, with the longitudinal steel reinforcing bars for the beam remaining continuous through the connection region. A strengthening ring beam is used to enlarge the connection zone in order to compensate for the possible decrease of the axial load-carrying capacity as a result of the discontinuity of the steel tube that encases the column. Two series of axial compressive tests on 32 beam-column specimens are reported. The first series of tests, including 5 full-scale connection specimens with CFST columns, show that with proper design, the axial loadcarrying capacity of the connection can be higher than that of the CFST column. The feasibility of this type of connection is verified. The second series of tests, including 27 specimens with only the connection zone, evaluate the ultimate strength of the connection. It is shown that the height and the area ratio of the reinforcement in the ring beam have significant influence on the axial load-carrying capacity of the connection zone. Taking into consideration the confinement produced by multiple layers of ring bars and the effect of local compression, a formula for predicting the ultimate axial compressive strength of this connection is proposed. The accuracy of the proposed formula is validated through comparisons of the theoretical and experimental results. [ABSTRACT FROM AUTHOR]

Silos in the form of cylindrical metal shells are usually supported on evenly spaced columns in applications where an access space is needed for the discharge of contained solids. In large silos a ring beam is used to distribute the column forces into the shell. The presence of discrete supports results in a circumferential non-uniformity of axial stresses in the shell. This non-uniformity leads to high local stresses that must be considered in assessing the possibility of shell buckling. Design standards provide recommendations for the buckling of shells under uniform axial compression, but are largely silent concerning stress peaks that may vary in width. Designers must resort either to onerous finite element analyses that include both geometric and material nonlinearities with imperfections (GMNIA) or trust to their own judgment. This paper presents a parametric study to develop resistance or capacity curves which can be used directly in design without the need for complicated analysis. The proposed design method uses only hand calculations apart from a simple linear finite element analysis to determine the degree of non-uniformity in the axial stresses. [ABSTRACT FROM AUTHOR]

This paper introduces a new type of connection between concrete-filled steel tubular (CFST) column and reinforced concrete (RC) beam through a transitional RC ring beam encircling the CFST column. Four scaled specimens, representing an interior-column joint, were tested under bi-directional cyclic loads to examine the seismic performance and the influence of the reinforcement on the joint. Load-deformation response, failure mode, strain distribution, and energy dissipative performance were presented. Test results indicated ductile performance and the multi-directional nature of the force system in the ring beam. Finite element models were also calibrated against test results and results from parametric analysis confirmed the effect of tube diameter and longitudinal reinforcement in the ring beam on the structural performance. [ABSTRACT FROM AUTHOR]

Innovative types of joints are recently used to connect concrete filled steel tubular laminated (CFTL) columns and reinforced concrete beams. The research on the calculation method of the moment capacity of innovative joints is strongly needed. Considering the axial compression load on the ring beams by the outside concrete, mechanical analysis of the failure isolation body of the ring beam was done using limit equilibrium method. This paper modifies the moment capacity calculation method of joints of ring beams and concrete filled steel tubular columns. The calculation results were about 28% higher than those of static tests, and based on this data the calculation method was further modified. Finally the modified calculation method was verified by experiments and ABAQUS finite element analysis under different axial compression ratios. And the results show that modified method can be used to calculate the moment capacity of joints of ring beams and CFTL laminated columns, and the calculation results are conservative. [ABSTRACT FROM AUTHOR]

Innovative types of joints are recently used to connect concrete filled steel tubular laminated ( CFTL) columns and reinforced concrete beams. Aimed at exterior joints of ring beams and concrete filled steel tubular laminated ( CFTL) columns, two monotonic loading tests and two cyclic loading tests for specimens with various radius-to-width ratios and three cyclic loading tests for specimens with various reinforcement ratios were earned out, to study the failure modes, capacity, stress distribution of bars and energy dissipation of the joints. The results show that; the joint ol ring beam and CFTL column is feasible and appropriate design can guarantee the structural design philosophy of 'strong-column-weak-beam' . For the failure modes of the joints, frame beam failure mode is prone to occur as reinforcement ratio gets larger. The capacity of the joint increases within limits as the radius-to-width ratio gets smaller or the reinforcement ratio becomes larger. The stresses of the longitudinal bars of the anchorage zone of the ring beam are high, and the stresses of inner and outside longitudinal bars are not uniform since the inner longitudinal bars barely yield. For the capacity of energy dissipation, the equivalent viscous damping coefficients show that the energy dissipation capacity is high. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the seismic and post-seismic behaviour of a new and innovative type of through-beam connection between a concrete-filled steel tubular (CFST) column and a reinforced concrete (RC) beam. In this new connection system, the steel tube is completely or partially cut with the cut or openings being at the corresponding beam location, with the longitudinal steel reinforcing bars for the beam remaining continuous through the connection region. A strengthening ring beam is used to enlarge the connection zone in order to compensate for the possible decrease of the axial load carrying capacity as a result of the discontinuity of the steel tube that encases the column. Cyclic loading tests and subsequent axial compressive tests are reported on six beam–column specimens. Based on the experimental results, the hysteretic response, the skeletal and post-cyclic static load–deflection curves, the strain, ductility, strength and the stiffness degradation and energy dissipation are discussed. The favourable seismic performance of the connection is demonstrated in the tests. A finite element model is then developed and validated by a comparison with the experimental results. The relative effects of the reinforcement ratio of the frame beam and the ring beam, and the axial compressive force in the column on the seismic behaviour of the connection are elucidated through parametric studies. [ABSTRACT FROM AUTHOR]

Abstract: Laser coating of nanodiamond (ND) on aluminum alloy A319 substrate was investigated using a diffraction-free ring beam. A 1000W continuous wave CO2 laser in the ring beam configuration heated the 25–35μm thick electrostatically sprayed ND powder layers on aluminum surface, melted a very thin layer (10μm) of aluminum in a controlled fashion and caused phase transition of ND to form 50–60μm thick ND/diamond-like carbon (DLC) coating. Significant improvements in friction, wear resistance and surface finish were observed in the ring beam method over the traditional Gaussian beam method suggesting that these thick (50–60μm) ND/DLC laser coatings can outperform the currently used thin (<4μm) chemically vapor deposited DLC coatings for aluminum parts in automobiles. [Copyright &y& Elsevier]

The spatial effects of ring beams in retaining structure with double-row piles for a deep foundation were investigated. The software of FLAC3D was employed to study the tip displacements and moments of the piles at different locations in retaining structure with doublerow piles and ring beams. Numerical results show that the tip displacements of pile at the corner are much less than the ones in the middle. The maximum tip displacement is located at the piles in the middle. Compared with the on-site measured data, above result match the test data very well. It is also found that the retaining structure with row piles has better synergistic reaction with ring beams. The deformation and internal force are affected by ring beams. The displacement and moment could also be limited by ring beams. Therefore, it is proposed that the spatial effect should be considered in the design of retaining structure with double-row piles. [ABSTRACT FROM AUTHOR]

Research on cylindrical and spherical tensegrity modules are extensively carried out. However research on other tensegrity modules is little reported. This paper presents an exploratory study on a new kind of tensegrity module – "torus". The topology of the torus tensegrity is firstly introduced. Then the initial form-finding of the torus tensegrity is discussed. The static and dynamic analysis of the torus tensegrity shows that prestressing has a stiffening effect on infinitesimal mechanism modes if the geometry is properly arranged. A new cable dome with a torus tensegrity employed as its ring beam is finally proposed. The behavior of the new dome is also examined. The work here will provide a reference for further research and application of the torus tensegrity. [ABSTRACT FROM AUTHOR]

A computer method based on the classical shell and plate theories is presented for the elastic analysis of cylindrical water tanks subjected to axisymmetrical loading and post-tensioning loads. A spherical dome or circular plate roof, cylindrical container, top and bottom ring beams together with a circular plate foundation are considered as possible components of a water tank in the flexibility formulation. Classical shell, plate, and ring beam theories are used to obtain flexibility coefficients. A computer program has been developed based on this formulation and successfully used in the design of post-tensioned concrete water tanks with diameters of 80 m built in Saudi Arabia. [Copyright &y& Elsevier]

This paper presents an experimental and numerical study on different retrofit solutions for stone masonry buildings with timber diaphragms in earthquake-prone regions, aiming at enhancing wall-to-diaphragm connections, diaphragms' stiffness, and masonry properties. The experimental results of incremental dynamic shake-table tests on three full-scale two-story buildings, complemented by material and component characterization tests, are initially summarized. The first building specimen was unstrengthened. The second one was retrofitted at the floor and roof levels with improved wall-to-diaphragm connections and a moderate increase in diaphragm stiffness. Connections were also improved in the third specimen together with a significant enhancement of diaphragm stiffness. The calibration of two numerical models, versus the experimental response of the retrofitted building specimens, is then presented. The models were further modified and reanalyzed to assess the effects of masonry mechanical upgrades, which could be achieved in practice through deep joint repointing or various types of jacketing. These solutions were simulated by applying correction coefficients to the masonry mechanical properties, as suggested by the Italian building code. The effectiveness of the experimentally implemented and numerically simulated interventions are discussed in terms of strength enhancement and failure modes. [ABSTRACT FROM AUTHOR]