PCI Journal Paper Title: Preliminary Results and Conclusions From the PRESSS Five-Story Precast Concrete Test Building

Pure precast beam-column systems incorporate unbonded reinforced at the critical sections, causing strain incompatibility between steel and concrete. As a result, classical section analysis method, well know for characterising monolithic concrete members, cannot be directly applicable to these systems. This paper provides a section analysis method suitable for precast members, incorporating, through an analogy with equivalent cast-in-place solution named “monolithic beam analogy”, an additional condition on the member global displacement. The proposed method was first validated with the experimental data from tests on beam-column Hybrid subassemblages. Using appropriate hysteresis rules and the response envelopes defined by the section analysis method, a prediction of the behaviour of the PRESSS test building was carried out. Satisfactory agreements obtained between the analytical and experimental results confirm the validity of the suggested methodology. Derivation of the method and experimental validation are herein presented.

PCI Journal Paper Title: An Overview of the PRESSS Five-Story Precast Test Building

Ultrahigh performance concrete (UHPC) is an advanced cementitious material which has excellent mechanical and durability properties, making it appropriate for the rehabilitation of concrete structures. This paper investigates the usage of a thin layer of UHPC overlaying a normal strength concrete (NC) deck. The behavior of the interface connection will have a significant impact on the overall structural and durability performance of the UHPC-NC composite deck system. An integrated experimental and analytical study was conducted to understand the influence of several variables, such as normal concrete strength, interface roughness, and curing condition on the shear transfer behavior across the interface between UHPC and NC. The laboratory testing was performed in two phases, including slant shear testing in Phase-I and flexural testing of composite deck specimens in Phase-II. A total of sixty test units with five different surface textures and three different concrete strengths were loaded to failure in Phase-I. Four 197 mm (7.75 in.) thick, 0.61 m (2 ft) wide, and 2.74 m (9 ft) long deck specimens with 38 mm (1.5 in.) thick UHPC overlay and different interface texture were tested to failure in Phase-II. The slant shear test results demonstrated that the shear transfer across the interface is adequate for overlay applications for all textures with roughness equal or more than 3 mm (0.12 in.) regardless of concrete strength, which was later confirmed by the composite deck specimen tests. The interface bond strength was not affected by curing conditions (heat treatment or ambient) used for UHPC. Current bridge design guidelines provide a conservative estimate for the UHPC-NC interface shear strength.

The 2010–2011 Canterbury earthquakes in New Zealand revealed (1) improved structural response resulting from historical design advancements, (2) poor structural performance due to previously identified shortcomings that had been insufficiently addressed in design practice, and (3) new deficiencies that were not previously recognized because of premature failure resulting from other design flaws. This paper summarizes damage to concrete walls observed in the February 2011 Christchurch earthquake, proposes links between the observed response and specific design concerns, and offers suggestions for improving seismic design of walls in the following areas: amount of longitudinal reinforcement in wall end regions, suitable wall thickness to minimize the potential for out‐of‐plane buckling, and minimum vertical reinforcement requirements.