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Several experimental studies have shown that rocking shallow foundations have beneficial seismic performance features: recentering and energy dissipation with little damage. A new publicly available database, “FoRDy” (Foundation Rocking—Dynamic), summarizes the results of dynamic physical model tests of single-degree-of-freedom-like structures supported on rocking foundations. It contains data from five centrifuge and three 1- g shaking table test series that were conducted at experimental facilities in the United States, Greece, and Japan. The database includes 200 model “case histories” that span a wide range of model sizes, soil and structure properties, and seismic excitations. It is compiled as the first step toward building a comprehensive dynamic rocking foundation database, and it has the potential to grow in the future. To illustrate its usefulness, the data are used to show example correlations between the peak drift ratio demand and selected ground motion intensity measures. The results suggest that peak ground velocity (PGV), peak ground displacement (PGD), and the geometric mean of the linear spectral displacement over the period range of 0.2–3 times the initial natural period predict the peak drift ratio response reliably.

Many engineers are hesitant to specify rocking foundations for ordinary bridges because of the unsubstantiated notion that rocking bridges are more susceptible to instability than conventional fixed-base bridges. A parametric study using a finite element model including large deformation effects compares the performance and stability of stiff, flexible, tall, and short hinging-column and rocking-foundation systems. Eighty different ground motions, scaled using incremental dynamic analysis, were considered. Results show that, in a probabilistic sense, bridges with rocking foundations are more stable than bridges with hinging columns if their fundamental periods are the same and if base shear coefficients to initiate hinging or rocking mechanisms are the same. Maximum drifts are not much affected by changing between rocking and hinging mechanisms except near collapse, but residual drifts are smaller for rocking systems. The results also challenge the notion that rocking systems require a different design approach than hinging column systems.

SUMMARY This paper presents new results of centrifuge model tests exploring the behavior of rocking shallow foundations embedded in dry sand, which provides a variety of factors of safety for vertical bearing. The results of slow (quasi‐static) cyclic tests of rocking shear walls and dynamic shaking tests of single‐column rocking bridge models are presented. The moment–rotation and settlement–rotation relationships of rocking footings are investigated. Concrete pads were placed in the ground soil to support some models with the objective of reducing the settlement induced by rocking. The behavior of rocking foundation was shown to be sensitive to the geometric factor of safety with respect to bearing failure, Lf/Lc, where Lf was the footing length, and the Lc was the critical soil‐footing contact length that would be required to support pure axial loading. Settlements were shown to be small if Lf/Lc was reasonably large. Placement of concrete pads under the edges of the footing was shown to be a promising approach to reduce settlements resulting from rocking, if settlements were deemed to be excessive and also had impacts on the energy dissipation and rocking moment capacity. A general discussion of the tradeoffs between energy dissipation and re‐centering of rocking foundations and other devices is included. Copyright © 2011 John Wiley & Sons, Ltd.

A metal-free method for efficient and chemoselective reduction of α-ketoamides using DMF/NaOH/H2O system has been developed.