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ACT Bus Passenger Station/Stop Design Guidelines Final Report May 25 2006

Prepared by: McCormickRankinCagney www.mrcagney.com consultants in transportation www.mrcagney.com Project Title and Description

Document Information:

Client Department of Public Works

Job Number 3209

Title – Over Height Vehicles: Review of Risk Management Strategies

Status Final

Prepared by McCormick Rankin Cagney Pty Ltd in conjunction with Parsons Brinckerhoff.

Date 7 April 2009

Quality Assurance Register

Issue Description Prepared Authorised

ByByBy Date ByByBy Date

a Draft GR 05/04

1 Final GR 07/04 GR 07/04

This document and information contained herein is the intellectual property of McCormick Rankin Cagney Pty Ltd (MRC) and is solely for the use of MRC’s contracted client. This document may not be used, copied or reproduced in whole or part for any purpose other than that for which it was supplied, without the written consent of MRC. MRC accepts no responsibility to any third party who may use or rely upon this document.

Kuripla Bridge - Over Height Vehicles Review of Risk Management Strategies .doc: 7/04/2009

Table of Contents

1. Introduction...... 1 2. Regulated Dimension Vehicles and Excess Dimension Vehicles ...... 3 3. Current Traffic Arrangement...... 5 4. Kuripla Bridge Design...... 6 5. Approach Routes and Height Clearances ...... 7 6. Assessment of Risk...... 10 7. Mitigation Options ...... 11 7.1 Options Considered ...... 11 8. Recommendations...... 15

Appendix A

Drawings illustrating the Kurilpa Bridge height clearance to (provided by the Contractor)

Appendix B Figure 1 Height clearance of adjacent bridge structures Figure 2: Bridge Survey (Source: Main Roads)

Appendix C Dwg 3209 – 01 Issue C: North Quay Barrier – Option 1

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1. Introduction

The State Government is currently constructing a new pedestrian and cycle bridge across the . The bridge is to be known as the ‘Kurilpa Bridge’.

The bridge will extend from Tank St on the northern side of the river to Montague Rd on the south side. The bridge crosses both North Quay and the Riverside Expressway. Construction is well advanced with the bridge expected to be opened by September 2009.

The bridge essentially has two structural elements. Across the first three eastbound of North Quay the bridge comprises a concrete structure. Across the two other eastbound traffic lanes of North Quay, which connect directly onto the Riverside Expressway, and across the four westbound traffic lanes of the Riverside Expressway the bridge comprises of a tensegrity structure which is a relatively light weight structure. The divergence of the middle along North Quay, created as a temporary construction detour for the construction of the S1 sewer in around 1999, means that traffic from any lane on North Quay could pass under the tensegrity structure.

It is understood that the tensegrity structure does not have the resistance characteristics of a typical concrete bridge structure if struck by a moving vehicle. As such the unique design of the tensegrity structure has raised questions from a risk management perspective including:

 What height clearance is appropriate to minimise or mitigate the probability that the ‘tensegrity’ structure being struck by a vehicle?

 If struck, under what circumstances would the damage be minor or catastrophic?

 Even if only minor damage was to occur could there be loss of life? and

 Even if only minor damage was to occur could the repair of the minor damage require closure of the Riverside Expressway for lengthy periods creating operational stress on the city’s inner road network? The three day forced closure of the Ann St on-ramp to the expressway in 2006 highlighted the importance of the expressway to the operational performance of the inner city network.

On 8 May 2007 the Department of Main Roads (‘Main Roads’) advised the Department of Publics Works that the minimum clear vertical height clearance under the bridge, where it crossed the expressway was to be 5.3m. Main Roads also indicated in the same correspondence that a reduced vertical clearance of 4.8m would be permitted subject to the provision of an early warning height barrier and positive stop barrier.

While surveys have confirmed that the Main Roads’ minimum height clearance has been achieved (ie 5.551m height clearance at southern edge line Ann Street on-ramp lane and 5.692m at the at edge line of the southern North Quay lane), Main Roads has requested

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implementation of permanent measures to eliminate the possibility of a vehicle striking the tensegrity structure.

Measures proposed by Main Roads include erection of permanent stop barriers; devices which have the ability to stop a 45t vehicle travelling at a speed of 60km/h. Main Roads has completed preliminary design of two permanent stop barriers to be located in North Quay, between Herschel St and Tank St and on the Ann St on-ramp to the expressway.

With construction of the tensegrity structure over the expressway nearing completion, Main Roads will be erecting, by 17 April 2009, signage warning motorists of the vertical height clearances. The signs will specify the height limits on the North Quay and Ann St approach to the Kurilpa Bridge, which are actually governed by the height of existing structures either side of the Kurilpa Bridge - 5.0m at the (westbound) and 4.3m at the Turbot St overpass (eastbound).

As part of a review of mitigation measures a workshop was conducted between Main Roads and the Department of Public Works on Monday 23 March 2009 to discuss the range of strategies to mitigate the possibility of an over height vehicle making contact with the tensegrity structure

The outcome of the workshop was to prepare this report with recommendations as to the mitigation strategies to be implemented prior to the opening of the Kurilpa Bridge. For the purpose of this report the term ‘over height vehicle’ includes:  Rigid and articulated vehicles;

 Vehicles with an indivisible or divisible load including construction vehicles carrying equipment or small machinery; and

 Cranes and the associated booms.

The report is for consideration by the Steering Committee overseeing the construction of the Kurilpa Bridge. Accordingly this report summarises the following:  Legislation relevant to the over dimensional vehicles;

 Existing traffic arrangement on North Quay and the Expressway;

 Design aspects of the bridge;

 Approach routes an over dimensional vehicle could use to come in contact with the bridge;

 An assessment of the risk of a vehicle striking the Kurilpa Bridge;

 The options considered for mitigating the risk;

 Recommendations.

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2. Regulated Dimension Vehicles and Excess Dimension Vehicles

The regulated dimensions of vehicles permitted on Queensland roads are specified in Part 3 of the Transport Operations (Road Use Management: Mass, Dimensions and Loading) Regulation 2005 . Clause 26, Division 2 of Part 3 of the regulation states that:

A person must not drive a vehicle on a road if the vehicle is higher than-

(a) for a vehicle built to carry cattle, horses, pigs pr sheep – 4.6m; or

(b) for a vehicle built with a least 2 decks for carrying vehicles when carrying a vehicle on the upper deck – 4.6m; or

(c.) for a double decker bus – 4.4m; or

(d) for another vehicle - 4.3m

Queensland Transport is the State government agency responsible for the management of vehicles travelling on Queensland roads including vehicles with excess dimensions and/or excess mass. The Queensland Transport document G uideline for Excess Dimension Vehicles in Queensland (Carrying Indivisible Articles and Special Purpose Vehicles ) is applicable for vehicles with a maximum length of 25m, a maximum width of 3.5m and a maximum height of 4.8m (which is only applicable to trailer combination vehicles operating on approved road train routes). The height limit applicable for all other over dimension vehicles is 4.6m. Section 8.5. of the Queensland Transport document relates to travel restrictions of all vehicles (covered by the guide).

Clause 8.5.1 states that:

A person must not drive an oversize vehicle or combination on the following roads:

(a) Pacific Motorway north of the intersection with ; or

(b) The Riverside Expressway; or

(c.) Western Arterial Road from Miskin Street, to Stafford Road….…..; or

(d) .

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Therefore, based on the Queensland Transport guide and the relevant Act, vehicles with a height of 4.6m or greater are not permitted on the Riverside Expressway. This infers that any vehicle with a height limit greater than 4.6m travelling on the Riverside Expressway, without a permit issued by Queensland Transport and the Queensland Police, would be in contravention of the guideline and hence the provisions of the relevant Act and regulations.

From the review of height clearances along the Riverside Expressway it is noted that there are a few locations, particularly in the vicinity of the Victoria Bridge, where the available height clearance is less than or equal to 4.6m.

Vehicles which exceed the dimensions specified in above guide must: comply with the Queensland Transport’s Performance Guidelines for Excess Dimensions. This guideline relates to vehicles which require pilots or escorts.

While most operators adhere to the regulations, evidence of vehicles striking existing bridges over the Riverside Expressway highlight that rogue operators, perhaps not fully aware of the height of their vehicle do attempt to travel along the expressway.

From the discussions at the workshop it seems apparent that the penalties for driver infringement of the height restrictions are minimal relative to the logistic costs associated with freight transport.

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3. Current Traffic Arrangement

North Quay is a one-way road carrying eastbound traffic. It is defined as a Suburban Route within the City Plan. North Quay essentially provides a connection from Coronation Drive to the Riverside Expressway, Victoria Bridge and William St. The road is under the jurisdictional responsibility of the Brisbane City Council. The speed limit along North Quay is 50km/h;

The Riverside Expressway (REX) carries both eastbound and westbound traffic and is defined as a Motorway within the Brisbane City Council City Plan. The expressway is under the jurisdictional responsibility of Main Roads. The sign posted speed limit along the expressway in the vicinity of the Kurilpa Bridge is 70km/h.

As indicated on the aerial photograph (Figure 1) below:

 North Quay in the vicinity of the bridge structure comprises of five eastbound traffic lanes. The two most northern lanes continue along North Quay to connect with William Street at Queen St. The two southern lanes connect directly onto the Riverside Expressway. These two southern lanes are physically separated from the other three lanes by a concrete traffic median. Based on survey information provided by Main Roads the median is approximately 600mm wide with approximately 1m between the edge lines of the adjacent through lanes. Only traffic from Coronation Drive is able to travel along these two lanes. The centre lane of the five North Quay lanes bisects immediately prior to the Kurilpa Bridge structural support column allowing motorists to enter directly onto the Riverside Expressway or continue onto the Victoria Bridge or William St. The creation of the divergence of the centre lane was implemented around the year 1999 to facilitate temporary construction works of the S1 sewer by the Brisbane City Council; and

 Westbound the expressway, in the vicinity of the bridge comprises the Herschel Street off ramp, two westbound lanes and the Ann Street on-ramp.

Figure 1: Aerial Photograph of the Riverside Expressway adjacent Tank St (Provided by Queensland Department of Main Roads)

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4. Kuripla Bridge Design

The Kurilpa Bridge is currently under construction.

When complete the bridge will extend from Tank Street, over both North Quay and the Riverside Expressway, to the southern embankment of the Brisbane River adjacent the recently opened Gallery of Modern Art. Supporting columns have been constructed in Tank St, between North Quay and the expressway, on the riverside of the expressway and on the opposing side of the river.

Based on information provided by others and from site inspections, it is understood that the bridge consists essentially of two types of structure:

 The section of bridge extending from Tank Street to the supporting column located between North Quay and the expressway is a concrete structure. As illustrated on the figures in Appendix A of this report, survey data provided by the contractor, indicates that the minimum vertical height clearance for this section of the bridge is 6.6.6.088m6. 088m088m; and

 The section of bridge extending from the supporting column located between North Quay and the expressway to the southern side of the river is a ‘tensegrity’ structure which is a relatively light weight structure. It is understood that the ‘tensegrity’ structure does not have the resistance characteristics of a typical concrete bridge structure if struck by a vehicle. As illustrated on the figures in Appendix A of this report, survey data provided by the contractor, indicates that the following minimum vertical height clearances exist under the tensegrity structure:

 Over the 3 eastbound expressway traffic lanes - 5.5.5.6925. 692692mmmm;

 Over the 3 westbound expressway traffic lanes including the Herschel Street off ramp will be 5.75.75.7815.7 818181mmmm; and

 Over the Ann Street on-ramp - 5.5.5.5515. 551551mmmm

The surveys confirm that the bridge has been constructed with a height clearance in excess of the minimum clear vertical height clearance of 5.3m required by Main Roads.

It is understood that the type of structure over the expressway is relatively lightweight (in comparison to a concrete structure) and suffer significant damage from the impact of an over height vehicle.

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5. Approach Routes and Height Clearances

As part of the review of the risk management measures existing height impediments on each possible approach route to the Kurilpa Bridge was investigated.

The location and height of existing height impediments along the approach routes leading the bridge is indicated on Figure 1 of Appendix B of this report. In preparing this report information on clearance heights of existing structures was sourced from the site inspections, information provided by the Department of Main Roads and from referencing the street directory.

The following is a summary of the structural height impediments along travel routes to North Quay:

West bound

 Route WWW1W111: Ann St to North Quay via the Ann St On ramp

No existing height impediment exits along this route. In fact, no height impediment exists between the Gateway Motorway Bridge over Kingsford Smith Drive at Eagle Farm and the ‘tensegrity’ structure when approaching the bridge via Ann St.

 Route W2W2W2:W2 George St to North Quay via the Ann St On ramp

Vehicles travelling along George St could also access North Quay, though given the constrained geometry of the inner city street network; it is unlikely a vehicle with a height clearance greater than 5.3m would be able to manoeuvre through the inner city streets without some form of a traffic control escort.

Eastbound

 Route EEE1E111: Coronation Drive to North Quay

There are three bridge structures along this route within close proximity of the Kurilpa Bridge namely the Boomerang St overpass, the Merivale Rail Bridge and the William Jolly Bridge.

As confirmed by Main Roads survey data, of the three structures the William Jolly Bridge has the lowest clearance of 5.285.28mmmm (eastbound traffic lane). Survey data obtained from Main Roads is provided in Figure 2 of Appendix B of this report.

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 Route EEE2E222: Hale St, Coronation Dr to North Quay

Along this route the William Jolly Bridge has the lowest clearance of 5.28m5.28m....

 Route EEE3E333:::: Hale St or Coronation Dr, Coronation Dr Off Ramp to Grey St, North Quay

This route is similar to Route E1 though a vehicle would need to exit Coronation Drive via the off ramp prior to the William Jolly Bridge and then continue through the recently upgraded signalised intersection at Grey St to enter directly into North Quay.

While traffic signage states that only buses are permitted to undertake the through movement at this intersection, there is no physical barrier preventing any motorists undertaking the movement, albeit in contravention of the TO(RUM) Act and Regulations.

 Route EEE4E444:: Countess St, Saul St (or Makerston St or Herschel St) to North Quay

Along this route the Countess St rail Bridge only has a height clearance of 4.4m.

 Route EEE5E555: Grey St, William Jolly Bridge Roma St, Saul St to North Quay and onto the Riverside Expressway

There is no impediment on this route.

 Route EEE6E666: Ann St, Roma St, Saul St to North Quay

Along this route the Turbot St overpass only has a has a height clearance of 4.9m

 Route E7E7E7:E7 ::: George St, Saul St, St (or Makerston St or Herschel St) to North Quay

While there is no height clearance less than 5.3m, the route is only possible when approaching George St from either Ann St or the Riverside Expressway off ramp of Elizabeth St (or to a lesser extent Margaret St). However given the size of vehicle to have a height equal to or greater than 5.3m, it is unlikely this vehicle would be able to manoeuvre through the inner city streets.

The investigation of the approach routes highlighted the following:

1. The Ann Street approach poses the greatest risk with no height impediment less 5.3m than for vehicles approaching the tensegrity structure;

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2. The exiting clearances of the Ann St off ramp (5.1m) and Victoria Bridge (4.7m) confirm that there are lower clearances on the expressway well prior to the tensegrity structure. Therefore westbound traffic travelling along the expressway, except for the Ann St traffic, does not pose a risk;

3. The lanes which approach North Quay from Coronation Drive are required to pass under the William Jolly Bridge which has a maximum height clearance of 5.36m (kerbside lane) which is 332mm lower than the minimum height clearance of tensegrity structure (ie 5.692m) under the southern North Quay traffic lanes. Therefore an over height vehicle would strike the William Jolly Bridge prior to coming in contact with the Kurilpa Bridge; and

4. Only two of the five lanes on North Quay would be able to come in contact with the tensegrity structure if a central median has constructed to prevent vehicles in the three northern lanes of North Quay accessing expressway.

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6. Assessment of Risk

Risk is a measure of the product of likelihood and consequence.

The following is a high level assessment of the risk of an over height vehicle striking the Kurilpa Bridge from either the North Quay approach or the Ann St approach:

North Quay

While based on Queensland Transport guidelines, a vehicle with a high clearance requirement over 4.6m would be defined as an ‘Excess Dimension’ vehicle and is not permitted to travel along the Riverside Expressway, the likelihood of an over height vehicle (ie >5.3m) travelling eastbound along North Quay is considered to be very low given the dominant eastbound approach route is Coronation Drive which already has a height clearance less than 5.3m.

If the likelihood of a vehicle with a physical height equal to or greater than 5.3m travelling eastbound along North Quay to access the Riverside Expressway (eastbound) is considered to be very low but the consequence of possible contact is considered to be high, based on structural engineers’ advice, the overall the risk an over height vehicle coming into contact with the bridge would need to be considered as ‘Medium’.

Riverside Expressway

With respect to vehicles approaching the Riverside Expressway via the Ann Street on- ramp, there are no known permanent height restrictions for the length of Ann Street from Kingsford Smith Drive other than the street guide signs which straddles Ann Street immediately past the George Street intersection.

In addition to the Queensland Transport guidelines, the Brisbane City Council did implement a truck ban in Ann St in 1995 which prohibits trucks with a Gross Vehicle Mass greater equal to or greater than 16t from accessing the Riverside Expressway from Ann St. It is understood that this prohibition has significantly reduced the volume of commercial vehicles, particularly articulated vehicles, accessing the expressway via Ann St.

The above suggest that the likelihood of a vehicle with a physical height greater than 5.3m travelling along Ann Street to access the Riverside Expressway would be low though of higher possibility than for the North Quay approach given the lack of physical impediments along this route. This suggests the risk of a vehicle coming into contact with the bridge from this approach has to be considered as ‘High’.

From the above assessment it can be concluded that measures need to be implemented to mitigate the possibility of an over height vehicle striking the tensegrity structure at both the North Quay approach and the Ann St approach.

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7. Mitigation Options

With the bridge scheduled to be operational by September 2009 and with the tensegrity structure already constructed without permanent stop barriers in place, the Main Roads has moved to install advanced signage advising motorists of the height limits. Installation is to be undertaken on 17 April 2009.

The section discusses the range of mitigation options discussed at the workshop to mitigate the possibility of an over height vehicle striking the ‘tensegrity’ structure. 7.1 Options Considered

During the workshop held in 23 March 2009, various options were discussed to achieve the design objective of mitigating the possibility of an over height vehicle striking the ‘tensegrity’ structure.

Options considered are discussed below.

 Electronic Detection

This type of measure involves the use of intelligent transport devices whereby an over height vehicle is detected and then electronic devices are activated to provide warning to the driver that they are approaching a height restriction.

The dynamic devices could include activation of a verbal message sign and/or changing signal phasing at traffic signals.

Height detection systems are already in operation:

 In Brisbane a the system is in operation on the southern side of the ; and

 The recently constructed Tugun Bypass has detection systems on the approaches to the tunnel.

The system would be appropriate from installation on the Ann St approach. The functional design of the system would primarily involve:

 Erecting detection devices across Ann St (on buildings);  Linking the system to variable message signs and other devices; and  Integrating the detection devices with the Council and State traffic control system.

The system would need to be operated and monitored by the Brisbane Metropolitan Traffic Management Centre (BMTMC). Following detection and verification a incident response plan may be needed to assist reroute the vehicle, presuming the motorists stopped prior to the bridge.

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The option is relatively low cost but its weaknesses are that the system relies on the driver taking evasive action and there is no assurance that a driver will observe the advice and respond accordingly. Also unless a diversion route is provided, there would be reluctance for drivers to change from their current route. Further, the risk does exist that in the event of power failure, the system will fail.

At best the detection system would provide an approach complementary measure providing a mechanism to disseminate advice to motorists.

 Permanently Stop Barrier( PSB)

Based on advice from Main Roads, this type of device would be designed can stop a vehicle travelling at 60km/h within 6m. Such devices do exist in isolated locations in Brisbane including the eastern approach to Ivory Street tunnel.

While the advantage of the device is that it will stop a vehicle there are inherent operational issues:

 The structure has the potential to severe a load, particularly a divisible load, which could result in the material becoming a projectile and potentially injuring other motorists or pedestrians;

 The device is very costly and would need to be relaced if severely damaged when struck; and

 The structure is designed to collapse on impact. This creates a hazard for motorists and pedestrians particularly within heavily pedestrianised areas of the inner city.

Main Roads has already completed preliminary design of a PSB being located over the single lane of the Ann St on-ramp and across the five traffic lanes of North Quay.

The PSB over the Ann St on ramp has design challenges including:

 It may require raising of the footpath between the on –ramp and the Law Courts;

 Service may need to be relocated; and

 The need for temporary closure of traffic lanes

The PSB over North Quay also has more complex design challenges including:

 The need to closure lanes in North Quay for long periods to facilitate construction; it is understood that this is not acceptable to Brisbane City Council;

 A complex footing design is required due to the presence of an extensive amount of services within the footpath; and

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 The reduction of the already narrow footpath along North Quay (northern side).

 Lane Closures

This option became evident when considering North Quay.

Of the 5 lanes along North Quay, three lanes pass under the section the Kurilpa Bridge which comprises the concrete structure. Advice from the structural engineers is that this structure is typical of other concrete structures and does not pose the risk of structural failure if struck by a vehicle compared to the tensegrity structure. Also the minimum vertical height clearance of this section on the bridge is 6.088m.

The other two lanes of North Quay pass under the William Jolly Bridge which has a maximum vertical clearance of 5.36mm which is approximately 330mm higher than the minimum vertical height clearance at the tensegrity structure (ie 5.69m).

The option of closing the remanent temporary access from middle North Quay lane onto the expressway would ensure all North Quay traffic approaching the tensegrity structure would have had to have passed under a lower height impediment in advance of the Kurilpa Bridge.

Site inspections, discussion with Main Roads and Brisbane City Council, review of survey information and preparation of a preliminary design concept indicate that:

 The existing traffic lanes are narrow;

 In addition to closing access to the expressway, the existing median would need to be replaced to prevent vehicles crossing the median – which does occur infrequently at the moment;

 An extruded single slope concrete barrier with a 630mm base with a 620mm Quadguard cushion would be an appropriate for of barrier and cushion;

 Based on a 500mm clearance to the barrier, as per the Main Roads planning manual, minor roadworks would be required at the Makerston St intersection to provide a 1.6m (min) distance between adjacent lanes; currently there is only 1.0m width. Further along North Quay the horizontal alignment of the north side kerb allows for widening of the median possibly with no roadworks. This will be subject to detail design.

A preliminary concept of the option is provided in Appendix C.

A concept plan of reducing the three northern traffic lanes along North Quay to two lanes to facilitate the introduction of the concrete barrier was prepared, however Council officers indicated that the reduction in through capacity would not be accepted.

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 Enforcement

An issue with enforcement is that there is no ability to stop a vehicle in Ann St or North Quay without blocking a traffic lane. This limits the ability for police or Queensland Transport officers to stop a vehicle in these locations.

The point of note from the workshop was that consideration should be given to increasing the penalty for driving an over height vehicle on prohibited routes.

 Tyre Shredding device

This was a concept which was discussed briefly and discarded. The measure would involve the activation on a mechanical device (presumably embedded into the pavement) which, following detection of an over height vehicle, would protrude from the pavement and puncher the vehicles types. These devices are more appropriate on a single lane approach; hence its application in North Quay would not be feasible. The concern was that the device would have the potential to create a safety issue.

 Water sheeting

It is understood this measure has been adopted for the tunnels in . It is based on a sheet of water falling across the traffic lanes to inform motorists to stop. Its application in Ann St and North Quay was not considered appropriate.

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8. Recommendations

The State government is currently constructing a new pedestrian and cycle bridge across the Brisbane River. The bridge is to be known as the ‘Kuripla Bridge’.

The bridge essentially has two structural elements - a concrete structure and a tensegrity structure.

The tensegrity structure extends over the Riverside Expressway. The minimum vertical height clearance is 5.551m (Ann St on –ramp) which exceeds the prior advice from Main Roads to allow a minimum of 5.3m.

It is understood that the tensegrity structure does not have the resistance characteristics of a typical concrete bridge structure if struck by a moving vehicle. Therefore vehicles need to be prevented from striking the structure.

A review of strategies to mitigate the possibility of an over height vehicle making contact with tensegrity structure has concluded that:

 Westbound traffic on the Riverside Expressway pass under a lower height impediment of the 4.4m (Victoria Bridge) prior to the Kurilpa Bridge;

 The maximum vertical clearance of the William Jolly Bridge is approximately 330mm lower than the minimum vertical clearance of the ‘tensegrity’ structure (eastbound);

 The Ann St approach has no impediments to over height vehicles and therefore a permanent stop barrier should be erected on the Ann St on- ramp;

 Given the cost and inherent issues with permanent stop barriers, the device should be implemented in conjunction with an electronic detection system which activates signage to provide advance warning to the driver of the height restriction. The electronic detection system and the PSB should be set to a vertical clearance level of 5.0m thereby providing protection to the William Jolly Bridge (westbound) in addition to the Kurilpa Bridge; and

 North Quay access to the expressway should be permanent closed with a single slope concrete barrier installed to separate the three northern traffic lanes on North Quay from the two southern lanes.

Other supporting measures which should be considered include:

 Increasing the penalty for motorists of heavy vehicles travelling on prohibited routes; and

 Increasing public awareness of the height limitations within the inner city network.

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Appendix A

Drawings illustrating the Kurilpa Bridge height clearance to Riverside Expressway (provided by the Contractor)

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Appendix B

Figure 1 Height clearance of adjacent bridge structures Figure 2: William Jolly Bridge Survey (Source: Main Roads)

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Appendix C

Dwg 3209 – 01 Issue C: North Quay Barrier – Option 1

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