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Observations in major earthquakes have shown that rockable structures suffered less to no damage. During rocking, that is, partial and temporary footing separations, the influx of seismic energy is interrupted and thus the impact of the base excitation is reduced. Rocking causes the structure to deform more rigid like. Consequently, the structure experiences less deformation along the height and thus a lower damage potential. Although many researchers have studied the influence of rockable footings, most of these are either analytical or numerical, and only a very few structures have been built with rockable footings worldwide, for example, the chimney at Christchurch Airport and the South Rangitikei Viaduct in New Zealand. Despite these studies, a thorough and understanding is not yet available, especially with respect to experimental validations. This work is the first to investigate the rocking behaviour of bridges with different slenderness using large‐scale shake table experiments. To limit the number of influence factors, a stiff footing support and the same fixed‐base fundamental frequency of the bridges were assumed. The result shows that the girder displacement and the footing rotation of the tall bridge do not always move in phase, which cannot be observed in the short bridge. The results demonstrate the important role of slenderness in the overall responses of rockable bridges. This behaviour cannot be observed in bridges with a commonly assumed fixed base since the slenderness effect cannot be activated. [ABSTRACT FROM AUTHOR]

During bridge design and assessment, effects of thermal actions are accounted for by means of a uniform temperature variation and temperature difference components. The uniform temperature variations cause changes in length and width of the structure, whereas the temperature difference components primarily cause curvatures and internal stresses. The effects of these strains on the superstructure depend on the structure's articulation and restraint. Design profiles used to model the temperature difference components vary between design codes, which can have a significant effect on the induced curvatures. Thermal data findings obtained from a comprehensive, year-long monitoring programme on Waterloo Bridge in London are examined, which allows comparison of these various models with performance data. The design thermal model in BS EN 1991-1-5 is examined, supplemented by the models from the Aashto and New Zealand codes. The measured uniform bridge temperature generally fell within the stipulated limits of BS EN 1991-1-5; however, at low temperatures the minimum deck temperature may be lower than the design relationship provided. The resultant moments implied from the measured vertical profiles: significantly exceed the worst-case values predicted by the UK model; exceed the Aashto model at different bridge sections; and do not exceed the New Zealand model. [ABSTRACT FROM AUTHOR]

This paper presents the assessment of historic seismic bridge performance of the New Zealand highway bridge stock from the 1968 Inangahua earthquake through to the 2016 Kaikōura earthquake. Spatial ground motion details based on recorded and observed ground motion intensities were used to estimate the peak ground acceleration (PGA), as a measure of the seismic demand at each bridge location. Across all events, a PGA of 0.05 g or higher was experienced on over 800 occasions across bridge sites. Damage characteristics were collated from available literature, with the majority of the highway bridges experiencing either no damage or only minor damage across all the events. At PGAs greater than 0.5 g, the number of bridges with moderate and major damage was still relatively small. There were also no apparent differences between the performance of bridges across the different design eras, despite the varied design and construction practices. Some shorter bridges may have performed better than expected due to the effect of abutment stiffness and damping, while some longer bridges may have performed well due to travelling wave effects. These findings will inform future assessment methods and design, and the accuracy of analytical modelling of the bridge stock. [ABSTRACT FROM AUTHOR]

Past earthquakes such as the Christchurch and Kaikoura events have highlighted the difficulties in residual capacity assessment and repair of plastic hinge damage in conventional reinforced concrete bridges. Also, with growing population densities in urban centres around the world, there is substantial interest in increasing earthquake resilience and minimising the disruption caused by new bridge construction. Two areas of research that address these aspects are low damage design and accelerated bridge construction. The aims of low damage design are to significantly reduce seismically induced damage to structural members, minimise residual drifts and limit damage to specifically designed components. At the University of Canterbury, New Zealand, within the bridge engineering space over the past decade or so, particular focus has been placed on these areas of research and their combination. This paper presents an overview of the extensive experimental work undertaken at the University of Canterbury on these topics for bridges. [ABSTRACT FROM AUTHOR]

State Highway 16 (SH16) is a motorway of significant strategic importance, connecting central Auckland to the city's western suburbs and beyond. It carries an average of 90 000 vehicles per day and runs through an environmentally sensitive coastal marine reserve. Two bridges on the route – Whau River Bridge and Causeway Bridge – were rehabilitated due to extensive chloride contamination as a result of exposure to the marine environment. This paper offers a holistic review of the inspection, durability assessment and design processes, and discusses construction, operation and maintenance details. The durability assessment considered deterioration mathematical modelling with regard to service life extensions of 25 and 50 years. A hybrid corrosion protection (HCP) system was selected as the preferred corrosion management solution. The system operates in two phases, initially energised using low-voltage direct current power to arrest ongoing corrosion and thereafter in galvanic mode to provide corrosion prevention. A structural health monitoring system was also designed and installed to offer long-term performance monitoring. The HCP system minimised physical works on site, negated the requirement for extensive replacement of chloride-contaminated concrete, allowed work to take place around the natural tide cycles and offers long-term protection. This is the first HCP system designed and installed in New Zealand and is believed to be the first of its kind for prestressed concrete in tidal waters. [ABSTRACT FROM AUTHOR]

The Auckland Harbour Bridge (Auckland, New Zealand), built in 1959 and widened in 1969, has approximately 125 000 m2 of external steel surfaces that have previously been maintained using a 'spot repair and overcoat' approach. This has been carried out since 1998 under a performance-specified maintenance contract using moisture-cured urethane coatings. In 2017, the Auckland Harbour Bridge Alliance embarked on a study to review the existing coatings maintenance regime and investigate alternative maintenance strategies. This paper summarises the findings of this investigation, from which a 40-year coatings maintenance plan was developed using net present value life-cycle cost analysis of zone painting. The maintenance plan was developed to achieve the lowest whole-of-life cost while meeting environmental protection requirements. [ABSTRACT FROM AUTHOR]

On 14 November 2016, the Mason River Bridge in North Canterbury, New Zealand, was rocked by one of the most complex and violent earthquakes ever recorded. This resulted in significant plastic hinging at the base of the pier columns. To avoid major costly repairs and strengthening, an innovative hardness and material testing technique was employed to determine the damage to reinforcement and residual capacity of the plastic hinges. This technique was developed for damaged buildings following the 2010 and 2011 Christchurch earthquakes, and is the first known example of its use for an earthquake-damaged bridge. Coupled with detailed non-linear time history analysis of the structure, this testing and analysis allowed the bridge's current and future seismic performance to be determined and helped justify the use of more conventional repairs, with major strengthening and seismic retrofit being avoided. This paper discusses the earthquake damage observed, the seismic performance of the structure, the advantages and disadvantages of the innovative material testing techniques, maintenance and repairs to the bridge and the expected performance of the repaired columns [ABSTRACT FROM AUTHOR]

The design and implementation of integral and semi-integral bridges has grown in prominence in New Zealand practice over the last two decades, and bridge designers in the country refer to the New Zealand Transport Agency (NZTA) Bridge Manual for design guidance. However, several issues related to the design and construction of integral bridges were identified as requiring either further investigation or clearer guidance for local design practice. These included non-seismic effects such as concrete creep, shrinkage and temperature, seismic effects and geotechnical issues including soil–structure interaction. Particularly, it was noted that there are no well-established earthquake design procedures for bridges with integral abutments and that the topic of soil–structure interaction required further guidance. NZTA research report 577, published in November 2015, was developed to sit alongside the Bridge Manual and provide local engineers with the necessary guidance for the design of integral bridges, including a description of the issues that need consideration to ensure excellent long-term performance. Report 577 also contains details of a review of the performance of numerous existing integral bridges in both New Zealand and California that have been subject to strong seismic events. This paper discusses the key issues for consideration in the design of integral bridges in non-seismic and seismic regions and the key recommendations for addressing these issues, and also provides examples of documented performance of some integral bridges in New Zealand. [ABSTRACT FROM AUTHOR]

Wooden bridges have been an important part of road and rail networks in New Zealand. While wooden structures have largely been replaced by concrete and steel on major arteries, they still have a place where lightweight, easily assembled structures are needed. These timber bridges are also an alternative to other materials in roads which carry relatively low traffic loads. In the last 10 years, there has been a resurgence in the installation of engineer-designed wooden structures. Contrary to the traditional method of construction, these prefabricated components are manufactured in a factory and brought to the job site where they can be assembled quickly with a minimum of cutting and drilling. In this document, we summarise the history and use of timber bridges in New Zealand. Most of the older bridges were constructed using Australian hardwood and native durable New Zealand timber. In the 1950s-1960s, preservative-treated timber particularly glue-laminated bridges were built. Currently, few bridges are built entirely from wood. However, in many smaller bridges, the superstructure and decking are built using treated wood. Using some specific case studies based on our historical service test data, we looked at the durability and maintenance requirements of wooden bridges in New Zealand. [ABSTRACT FROM AUTHOR]

At 00:02 on 14th November 2016, a Mw 7.8 earthquake occurred in and offshore of the northeast of the South Island of New Zealand. Fault rupture, ground shaking, liquefaction, and co-seismic landslides caused severe damage to distributed infrastructure, and particularly transportation networks; large segments of the country's main highway, State Highway 1 (SH1), and the Main North Line (MNL) railway line, were damaged between Picton and Christchurch. The damage caused direct local impacts, including isolation of communities, and wider regional impacts, including disruption of supply chains. Adaptive measures have ensured immediate continued regional transport of goods and people. Air and sea transport increased quickly, both for emergency response and to ensure routine transport of goods. Road diversions have also allowed critical connections to remain operable. This effective response to regional transport challenges allowed Civil Defence Emergency Management to quickly prioritise access to isolated settlements, all of which had road access 23 days after the earthquake. However, 100 days after the earthquake, critical segments of SH1 and the MNL remain closed and their ongoing repairs are a serious national strategic, as well as local, concern. This paper presents the impacts on South Island transport infrastructure, and subsequent management through the emergency response and early recovery phases, during the first 100 days following the initial earthquake, and highlights lessons for transportation system resilience. [ABSTRACT FROM AUTHOR]

The transport infrastructure was majorly affected by the 14th November 2016 Kaikōura Earthquake. Severe vertical and horizontal peak ground accelerations generated high inertial forces, land-slides, and liquefaction. Most of the bridges in the Hurunui, Malborough and Kaikōura districts were critical nodes to the railway and road networks. In total, 904 road bridges across those districts were affected. Two reached the life safety limit state, suffering severe damage, however, most of the affected bridges experienced only minor to moderate damage. This paper describes the structural performance of the most severely damaged bridges based on observations made from site inspections. In addition to this, several performance issues have arisen from this event and are posed in this paper, hopefully to be addressed in the near future. [ABSTRACT FROM AUTHOR]

During seismic assessments of bridges where there is a lack of construction documentation, one method of determining likely structural detailing is to use historic design standards. An overview of the New Zealand bridge seismic standards and the agencies that have historically controlled bridge design and construction is presented. Standards are grouped into design era based upon similar design and loading characteristics. Major changes in base shear demand, ductility, foundation design, and linkage systems are discussed for each design era, and loadings and detailing requirements from different eras were compared to current design practices. Bridges constructed using early seismic standards were designed to a significantly lower base shear than is currently used but the majority of these bridges are unlikely to collapse due to their geometry and a preference for monolithic construction. Bridges constructed after the late 1970s are expected to perform well if subjected to ground shaking, but unless bridges were constructed recently their performance when subjected to liquefaction and liquefaction-induced lateral spreading is expected to be poor. [ABSTRACT FROM AUTHOR]

The article offers information on the design, construction , and material selection of the Te Wero Bridge in Auckland, New Zealand. It notes that the design was prepared by Hyder Consulting Ltd. with architect Denton Corker Marshall and electrical and mechanical consultant Kenneth Grubb Associates Ltd. Furthermore, it mentions the usage of lightweight aluminum decks and counterweight system that offer low-energy, low-maintenance and sustainable solution to the bridge.

Repeated counts of road-killed animals have revealed sites where possums (Trichosurus vulpecula), rabbits (Oryctolagus cuniculus), hedgehogs (Erinaceus europaeus), gulls (Larus dominicanus, L. novaehollandiae) and shags (Phalacrocorax carbo) were killed in unusual numbers. These "blackspots" were not correlated with the volume of traffic, but were mapped at or near places where animals are presumed to crowd together or were most likely to venture onto the road. For example, in Hawkes Bay, 81% of possum corpses were counted on or within 200 m of road bridges, and a disproportionate number of hedgehogs were also killed on bridges or approaches to bridges. At least in this area, human and animal traffic blackspots did not coincide. I suggest that this information could be useful to agencies controlling the spread of tubercular possums, and the technique of systematic counting of road-kills could be extended to National Parks and other areas of natural interest. [ABSTRACT FROM AUTHOR]

Presents details of three case studies of scour damage for New Zealand bridges. Methodology for prediction of scour depths; Qualitative analysis of expected scour development in the Bulls Road Bridge crossing the Rangitikei River; Quantitative prediction of scour depths for pier B of the Blackmount Road Bridge crossing the Mararoa River.

Objectives: Safety barriers to prevent suicide by jumping were removed from Grafton Bridge in Auckland, New Zealand, in 1996 after having been in place for 60 years. This study compared the number of suicides due to jumping from the bridge after the reinstallation of safety barriers in 2003. Methods: National mortality data for suicide deaths were compared for three time periods: 1991-1995 (old barrier in place); 1997-2002 (no barriers in place); 2003-2006 (after barriers were reinstated). Results: Removal of barriers was followed by a fivefold increase in the number and rate of suicides from the bridge. These increases led to a decision to reinstall safety barriers. Since the reinstallation of barriers, of an improved design, in 2003, there have been no suicides from the bridge. Conclusions: This natural experiment, using a powerful a-b-a (reversal) design, shows that safety barriers are effective in preventing suicide: their removal increases suicides; their reinstatement prevents suicides. [ABSTRACT FROM AUTHOR]