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This paper presents the flexural behavior of notched steel beams repaired with carbon fiber-reinforced polymer (CFRP) strips. A combined experimental and computational approaches are used to examine local plasticity near the damage and the effects of CFRP-repair. A modeling approach is proposed to take into account the bond-slip behavior of CFRP-steel interface. The experimentally validated models are further used to conduct a parametric study addressing various engineering properties of CFRP composites and adhesives. The CFRP-repair is shown to restore the strength of the damaged beam. The CFRP strip relieves the stress concentration resulting from the presence of the notch, reducing the high local plasticity. The parametric study confirms the improved effectiveness of high modulus CFRP (i.e., exceeding 150 GPa) in affecting repairs of steel members. Under static loading conditions, the stiffness of the adhesive bond line influences the local behavior of the CFRP-steel interface but has little effect on the overall member behavior.

This paper presents a simplified modeling strategy for simulating the nonlinear behavior of reinforced concrete (RC) structures under seismic loadings. A new type of Euler–Bernoulli multifiber beam element with axial force and bending moment interaction is introduced. To analyze the behavior of RC structures in the axial direction, the interpolation of the axial strain is enriched using the incompatible modes method. The model uses the constitutive laws based on plasticity for steel and damage mechanics for concrete. The proposed multifiber element is implemented in the finite element Code_Aster to simulate the nonlinear behavior of two different RC structures. One structure is a building tested on a shaking table; the other is a column subjected to cyclic loadings. The comparison between the simulation and experimental results shows that the performance of this approach is quite good. The proposed model can be used to investigate the behavior of a wider variety of configurations which are impossible to study experimentally.

The force from a tsunami will damage buildings, such as houses, bridges, and many other coastal infrastructures. The impact and drag force of a tsunami depend on the scale and the characteristics of the tsunami as well as the infrastructures' characteristics.

This study was conducted using physical modeling to determine the effect of openings and protection on buildings to reduce the effects of a tsunami attack. The openings were symmetrical about the front and rear walls and were oriented in the direction of the tsunami. Barriers with dimensions that were the same width and three times higher than the building and of various lengths were used to simulate protection against a tsunami.

The results indicated that the force on the buildings depends on but is not linearly correlated to the opening. The barrier upstream of the building significantly reduced the force depending on its distance to the building and the surge Froude number; however, the openings still play an important role in reducing the force on a protected building. Simple equations for practical use are proposed to calculate the tsunami force on a building with openings with or without protection.

Numerical simulation is an important measure to study the seismic performance of buckling-restrained braced frames (BRBFs). Practically, some simplified models, such as the elastic–plastic with kinematic hardening model and the elastic perfectly-plastic model, are used to simulate the behavior of buckling-restrained brace (BRBs). To provide structural engineers the reference of errors when simplified models are used, this paper comparatively evaluates the effect of the BRB model on seismic structural responses using the OpenSees software. A comparison is made on six-storey and 16-storey BRBFs with rigid beam-to-column connections; these are designed according to Chinese seismic design code. Moreover, the effects of the post-yielding stiffness ratio of frame $\alpha$ and the stiffness ratio of BRB to frame $\beta$ on the errors are specifically investigated through a parametric study of both BRBFs. The results show that the seismic response average errors of the simplified models are mostly less than 5%, which satisfies the engineering requirements.

This paper is to understand and model the thermomechanical response of the rotary forged WHA, uniaxial compression and tension tests are performed on cylindrical samples, using a material testing machines and the split Hopkinson bar technique. True strains exceeding 40% are achieved in these tests over the range of strain rates from 0.001/s to about 7,000/s, and at initial temperatures from 77K to 1,073K. The results show: 1) the WHA displays a pronounced changing orientation due to mechanical processing, that is, the material is inhomogeneous along the section; 2) the dynamic strain aging occurs at temperatures over 700K and in a strain rate of 10^-3 1/s; 3) failure strains decrease with increasing strain rate under uniaxial tension, it is about 1.2% at a strain rate of 1,000 1/s; and 4) flow stress of WHA strongly depends on temperatures and strain rates. Finally, based on the mechanism of dislocation motion, the parameters of a physically-based model are estimated by the experimental results. A good agreement between the modeling prediction and experiments was obtained.

Sandbars are often present in the nearshore zones of sandy coasts. As a result of the interaction with the incoming waves, sandbars change in shape and location over time. Trends in cross-shore sandbar behavior can often be observed on many timescales, ranging from a few months to several years. Models for sandbar behavior can be specified on different abstraction levels and corresponding scales. In the present work we investigate the ability of two models specified on different abstraction levels to predict long-term (several months) sandbar behavior, using a high-resolution 15 year-long profile dataset collected at the Hasaki Oceanographic Research Station in Japan. We find that it is very difficult to predict the rate of offshore-directed trends in sandbar behavior on the timescales of months, resulting in overall poor model performance. We discuss the implications of our findings for the application of models in the understanding of long-term sandbar behavior.

In this paper we present the first results of beach profile hindcasting with XBeach using recently measured coastal data acquired under storm conditions at eight European sites, including a comparison to model results obtained with off-the-shelf models. The results show consistently that the XBeach has skill in predicting the coastal profile, albeit that in most cases the erosion around the mean water line is overpredicted and the depositions at the lower beach face are overpredicted. The causes for this model effect are under active investigation but not resolved yet. Likely candidates are the modeling of onshore (asymmetry) transports which reduces the offshore transports due to undertow (currents) or the modeling of sediment motion in the swash zone.

Four inlets (Johns Pass and Blind Pass; and New Pass and Big Sarasota Pass) in two multi-inlet systems along the West-central Florida coast were studied. Johns Pass, New Pass, and Blind Pass are dredged every 4-9 years, whereas Big Sarasota Pass has never been dredged. The goal of this study was to investigate the morphodynamics of the four inlets and the influences of channel dredging on the flow patterns over the ebb tidal delta and sediment bypassing. Time-series aerial photographs and bathymetric maps starting from the 1920s were analyzed to assess the pathways of sand bypassing and morphodynamics at the inlets. The Coastal Modeling System (CMS), computing wave, current, sediment transport, and morphology change of tidal inlets, was applied and reproduced the observed medium-term morphology changes. CMS is then used to investigate influences of channel dredging on inlet morphodynamics.