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This paper presents a simplified direct displacement design (DDD) procedure which was used to design the shear walls for a six-story woodframe structure. The building was tested in the final phase of a Network for Earthquake Engineering Simulation (NEES) project. Specifically, NEESWood Capstone Building was designed to meet four performance expectations: damage limitation, life safety, far-field collapse prevention (CP), and near-fault CE The performance expectations are defined in terms of combinations of interstory drift limits and prescribed seismic hazard levels associated with predefined nonexceedance probabilities. To verify that design requirements were met, a series of nonlinear time-history analyses (NLTHAs) was performed using suits of both far-field and near-fault ground motion records. The distributions of interstory drifts obtained from the NLTHA confirm that the Capstone Building designed using DDD meets all four target performance expectations, thereby validating the DDD procedure. Additionally, collapse analysis in accordance with the recently proposed Applied Technology Council project 63 (ATC-63) methodology was performed. The results of incremental dynamic analyses confirmed that the Capstone Building designed using the DDD procedure has adequate capacity margin against collapse, as dictated by the ATC-63 methodology. DOI: 10.1061/(ASCE)ST.1943-541X.0000181 CE Database subject headings: Displacement; Wood structures; Structural design; Shear walls; Earthquake engineering; Seismic effects. Author keywords: Displacement-based design; Wood structures; Shear walls; Earthquake engineering; Seismic hazard; Structural engineering; Performance-based design.

A series of large-scale shaking table tests is conducted for a high-rise building structure subjected to long-period ground motions. A test method is developed to preserve the original dimensions of structural members of a prototype building that has 21 stories with a total height of 80 m. The test specimen consists of a four-story, two-span by one-bay steel moment frame and three substitute layers placed on top of the moment frame. The substitute layers, which consist of concrete slabs and rubber bearings, are arranged to represent the upper stories of the prototype. From preliminary vibration tests, equivalence between the test specimen and the prototype is verified in terms of the lower mode natural periods and corresponding mode shapes. The test specimen when subjected to long-period ground motions exhibits cumulative ductilities more than four times those expected in Japanese seismic design, while the maximum story drifts remain nearly the same as those considered in the design. A number of cyclic inelastic deformations caused fractures at the bottom flanges of beam ends. According to these observations, the combination of large cumulative ductility demand, the weld quality of the field weld connections, and the promotion of strain concentrations at the toe of the bottom flange weld access hole by the presence of floor slabs caused the fractures and resultant smaller cumulative ductility relative to that observed in the bare beam tests. DOI: 10.1061/(ASCE)ST.1943-541X.0000161 CE Database subject headings: Buildings, high-rise; Ground motion; Shaking table tests; Seismic effects; Beams; Columns; Connections. Author keywords: High-rise building; Long-period ground motion; Shaking table test; Seismic performance; Beam-to-column connections.

This work has two objectives. The first objective is to introduce structural engineers to the experiment design technique, whose future applications may include, for example, the total response of tall buildings, the strength reserve of statically indeterminate structures with nonlinear behavior, for which the duration of each run is large, and the aerodynamic response of a structure under a flow with a variety of simulated flow parameters. The second objective is to show, by using the experiment design technique, that wind load factors for tall buildings depend significantly upon uncertainties with respect to the natural frequencies of vibration and the damping ratios. Because this dependence is disregarded in the ASCE 7-05 Standard, wind load factors specified therein can lead to safety levels that are significantly lower for flexible buildings than for rigid buildings. An unexpected result of the study is that estimates of wind effects based on peak gust speeds entail nonnegligible errors. Consideration should therefore be given to replacing peak gust speeds by sustained wind speeds. DOI: 10.1061/(ASCE)0733-9445(2010)136:2(160) CE Database subject headings: Damping; Structural design; Frequency; Buildings, high-rise; Wind speed.

The Civil Engineering community has long needed methods of accurate global displacement measurement for use in construction and more recently in the areas of structural health monitoring. Global Positioning Systems (GPS) provide one answer to this challenge, with rapid advancements in the available sampling rates and tracking resolution. However, as a relatively new dynamic sensing technology, GPS performance must be thoroughly validated before its application in full scale. This paper details an experimental program with this aim, documenting the performance of a high-precision GPS in terms of its background noise and dynamic tracking ability, while providing position quality thresholds suitable for qualifying the accuracy of tracking in full scale. Given the performance observed in these studies, considerations for full-scale deployment are offered as well as an assessment of its efficacy in monitoring the dynamic motions of a tall building through the Chicago full-scale monitoring project. DOI: 10.1061/(ASCE)0733-9445(2006)132:8(1242) CE Database subject headings: Displacement; Measurement; Structural reliability; Global positioning; Buildings, high-rise; Dynamic response.

A multistory factory building with elevated access allows loading and unloading of the raw materials and finished products right in front of each factory unit. This enhances the land productivity of land-scarce Singapore. However, container trucks traveling within the building may cause vibration of a production floor where high-precision equipment is located. In this study, a dynamic vehicle model is established to simulate a 40-ft container truck. The road roughness is represented by a power spectral density function according to ISO 8606. The random response of a typical production floor is analyzed by the fully coupled vehicle-structure interaction method as well as the decoupled moving dynamic nodal loading method. Compared with the acceleration and velocity acceptance criteria, the random response results show that the vertical response of the production floor to the container truck traveling at 15, 30, and 40 km/h over road classes B and C is generally acceptable. However, the maximum vertical vibration may exceed the more stringent criteria for some extremely high-precision equipment.