AITPM national newsletter October 2008 president's report

It’s a pleasure for me to be penning my first President’s Message for the AITPM Newsletter. I am eagerly looking forward to serving the Institute and members over the coming couple of years. First though, I’d like to congratulate Andrew Hulse for steering the good ship AITPM over the past two years, bringing so many initiatives to the fore, including the Certified Transport Planner (CTP), stronger ties with other organisations and agencies such as IPENZ and Austroads, mutually beneficial sponsorship arrangements, and sharing his enthusiasm towards the Thunderbirds. Personally and largely thanks to my kids’ domination of the TV I’m a bit keener on the other great British sixties sci-fi classic, Doctor Who. Maybe we can generate a “favourite Doctor” dialogue in the Newsletter.

AITPM national newsletter November 2008 president's report

As we’re moving toward the end of the year, it’s not hard to notice everyone starting to rush a bit more. So much so, that in some cases people can lose their cool when they’re out and about. Recently I viewed an episode of Jenny Brockie’s Insight program on SBS on the topic of “rage”. The program covered many areas of life, but it highlighted the issue of rage against taxi drivers in Melbourne and showed some archival footage of the recent taxi drivers’ protest on the issue, next to Flinders Street Station. Serendipitously, perhaps, I picked up Brisbane’s City News as I was eating lunch in town a few days later, and there was an article on Brisbane taxi stand supervisors, citing that some feared to go to work on Friday and Saturday nights as they were not infrequently assaulted by drunken revellers waiting in the long queues for their taxi ride home.

AITPM national newsletter December 2008 president's report

It’s fast approaching the end of the year and the festive season, and I have a few things on my mind. First, how I’ll fit in all of my holiday plans and projects within my period of leave, which always seems to pass oh so quickly! But more important are the two issues of global financial uncertainty and safe travel. Judging by what is in the media, it appears to be proving difficult for any self respecting financial industry specialist to define and grapple with the so-called current economic crisis, let alone those of us who have not been formally and extensively schooled in the sciences of finance and economics. Perhaps the latter is even more of a “black art” than the discipline of transport planning. The situation has affected all of us with our superannuation and/or share portfolios; however, judging by the still-crowded shopping centres in many areas, the downstream general economic impacts appear to be less serious in Australia than in other developed countries, even with the significant market fluctuations taking place. There are many important decisions facing Australian governments, from the top down, on how they manage their budgets and spending. Infrastructure spending is in competition with other necessities such as the public health system and education. But it appears that infrastructure is an avenue of public spending that, over all time windows, may be able to significantly bolster local economies and that of the nation as a whole. This, however, is against the spectre of deficits. I would suggest that now, more than ever, we as transport and other professionals within the system, should use our knowledge and experience to take a key role in helping government and the private sector make sound decisions on infrastructure planning, delivery and management.

AITPM national newsletter president's report February 2010

A belated Happy New Year fellow AITPM members! I trust that you have had a chance to take a break from your routine, and take time out to enjoy company with family and friends, as well as our wonderful surrounds.

AITPM national newsletter president's report March 2010

As a tertiary educator, business is now starting to heat up for my colleagues and me as Semester 1 commences. I’d like to take this opportunity to wish all readers who are students or academic staff, whether sessional or full-time, a successful year of teaching to, and learning more about, the transport profession. I’d also like to note the important role played by our AITPM National Council Education Coordinator, being fulfilled by Victoria Branch President Mr Tony Fitts, along with all of our branches’ Education Coordinators.

AITPM national newsletter president's report April 2010

Well, it has been Clem 7 month here in Brisbane and my impression is “so far, so good!” For those of you who know Brisbane, the four lane twin Clem Jones Tunnel (M7) is approximately 4.5km long, and connects Ipswich Road (A7) at the Princess Alexandra Hospital on the south side with Bowen Bridge Road (A3) at the Royal Brisbane Hospital on the north side. There are also south access ramps to the Pacific Motorway and east access ramps to Shafston Avenue (headed to/from Wynnum). Brisbanites have been enjoying a three week no-toll taste test, and I paced through it one evening with minimal fuss. The tunnel seems to have eased the congestion at the Stanley Street on-ramp to the Pacific Motorway quite a bit, and Ipswich Road – Main Street through the ‘Gabba. One must watch the signage carefully, but once we get used to the infrastructure, this will not likely be problematic. It will be interesting to see how traffic behaves when the system settles after tolling, which has likely commenced by the time you’re reading. I believe a passenger car toll is about $4.20 one way but saves about 24 signalised intersection pass-throughs.

AITPM national newsletter President's report May 2010

We’ve had a bit of sticker shock in these parts. Well, apparently. Since my last missive, Brisbane’s Clem Jones Tunnel which was initially free now has a toll, at least partially, at the introductory rate of $2.95 for a one-way car ride between 5a.m. and midnight – free overnight. From 9 May 2010 the toll will be $4.28. Since the introductory toll was introduced, use of the tunnel appears to have declined somewhat – no surprise to transport professionals I suppose. An additional factor may have been that the “novelty value” of driving through the tunnel for free had worn off. This demonstrates to me that much of the community may still see the use of road infrastructure as a rite of passage, with only some actually weighing up the true value of their travel time and vehicle wear and tear against their out of pocket (or onto credit card) cost. Thus, we’re in pioneering times and the role of transport economics in the overall transport infrastructure planning realm is of considerable importance – especially as much of the new big ticket infrastructure is likely to be tolled into the future. The Queensland Premier, Anna Bligh, made poignant commentary about Brisbane City Council’s tunnel use in that such infrastructure is built for future times and not just as a quick fix for current traffic problems. My expectation is that once Airport Link, which is really the northern half of the corridor, opens in 2012, there will be a significant spike in Clem7 usage.

AITPM national newsletter President's report June 2010

This is my penultimate report as National President of the Australian Institute of Traffic Planning and Management, Inc. As an academic, I would like to take this opportunity to raise some issues and challenges I see in transport professional education in Australia. My general view is that the transport profession has until recently been less conspicuous to others as an identifiable discipline. This is both a blessing and somewhat of a curse. People mostly enter, or sometimes fall into, the transport profession having taken a degree in civil engineering, other engineering, urban and regional planning, economics, industrial psychology, business, followed by the less obvious disciplines. This order is probably about relative to the proportion of members’ background qualifications in our ranks too. However, once a graduate destined to become a transport professional has spent about five years or so out of the academic estuary, they tend to specialise in an area that cannot necessarily be easily correlated to the well known courses I have rattled off above. I can say from experience that it is not out of the question to see SIDRA models having been prepared by a transport professional who did not take traffic engineering as part of a civil engineering degree. So I see a couple of key challenges for the transport profession, which happens to be represented by a number of bodies, with our AITPM perhaps being the peak body, into the future,

AITPM national newsletter President's report July 2010

I’d like to re-state AITPM’s mission, which is “Growing Traffic Skills and Knowledge to Deliver Sustainable Transport.” The aims of the Institute are to advance traffic planning and management; to increase the knowledge of its members by encouraging free discussion, exchange of ideas and research in this field; and to provide a central point of reference for practitioners.

Load-sharing in heavy vehicle suspensions : new metrics for old

Dynamic load sharing can be defined as a measure of the ability of a heavy vehicle multi-axle group to equalise load across its wheels under typical travel conditions; i.e. in the dynamic sense at typical travel speeds and operating conditions of that vehicle. Various attempts have been made to quantify the ability of heavy vehicles to equalise the load across their wheels during travel. One of these was the concept of the load sharing coefficient (LSC). Other metrics such as the dynamic load coefficient (DLC), peak dynamic wheel force (PDWF) and dynamic impact force (DIF) have been used to compare one heavy vehicle suspension with another for potential road damage. This paper compares these metrics and determines a relationship between DLC and LSC with sensitivity analysis of this relationship. The shortcomings of the presently-available metrics are discussed with a new metric proposed - the dynamic load equalisation (DLE) measure.

Development of a software model of a heavy vehicle suspension for research

A Simulink Matlab control system of a heavy vehicle suspension has been developed. The aim of the exercise presented in this paper was to develop a Simulink Matlab control system of a heavy vehicle suspension. The objective facilitated by this outcome was the use of a working model of a heavy vehicle (HV) suspension that could be used for future research. A working computer model is easier and cheaper to re-configure than a HV axle group installed on a truck; it presents less risk should something go wrong and allows more scope for variation and sensitivity analysis before embarking on further "real-world" testing. Empirical data recorded as the input and output signals of a heavy vehicle (HV) suspension were used to develop the parameters for computer simulation of a linear time invariant system described by a second-order differential equation of the form: (i.e. a "2nd-order" system). Using the empirical data as an input to the computer model allowed validation of its output compared with the empirical data. The errors ranged from less than 1% to approximately 3% for any parameter, when comparing like-for-like inputs and outputs. The model is presented along with the results of the validation. This model will be used in future research in the QUT/Main Roads project Heavy vehicle suspensions – testing and analysis, particularly so for a theoretical model of a multi-axle HV suspension with varying values of dynamic load sharing. Allowance will need to be made for the errors noted when using the computer models in this future work.

Overloading truck traffic study and strategy to minimise it

Overloaded truck traffic is a significant problem on highways around the world. Developing countries in particular, overloaded truck traffic causes large amounts of unexpected expenditure in terms of road maintenance because of premature pavement damage. Overloaded truck traffic is a common phenomenon in developing countries, because of inefficient road management and monitoring systems. According to the available literature, many developing countries are facing the same problem, which is economic loss caused by the existence of overloaded trucks in the traffic stream. This paper summarizes the available literature, news reports, journal articles and traffic research regarding overloaded traffic. It examines the issue of overloading and the strategies and legislation used in developed countries.

Identifying relationship between skid resistance, road characteristics and crashes using probability-based risk approach

Road accidents are of great concerns for road and transport departments around world, which cause tremendous loss and dangers for public. Reducing accident rates and crash severity are imperative goals that governments, road and transport authorities, and researchers are aimed to achieve. In Australia, road crash trauma costs the nation A$ 15 billion annually. Five people are killed, and 550 are injured every day. Each fatality costs the taxpayer A$1.7 million. Serious injury cases can cost the taxpayer many times the cost of a fatality. Crashes are in general uncontrolled events and are dependent on a number of interrelated factors such as driver behaviour, traffic conditions, travel speed, road geometry and condition, and vehicle characteristics (e.g. tyre type pressure and condition, and suspension type and condition). Skid resistance is considered one of the most important surface characteristics as it has a direct impact on traffic safety. Attempts have been made worldwide to study the relationship between skid resistance and road crashes. Most of these studies used the statistical regression and correlation methods in analysing the relationships between skid resistance and road crashes. The outcomes from these studies provided mix results and not conclusive. The objective of this paper is to present a probability-based method of an ongoing study in identifying the relationship between skid resistance and road crashes. Historical skid resistance and crash data of a road network located in the tropical east coast of Queensland were analysed using the probability-based method. Analysis methodology and results of the relationships between skid resistance, road characteristics and crashes are presented.

Investigation into travel modes of TOD users : impacts of personal and transit characteristics

Transit Oriented Developments (TODs) are often designed to promote the use of sustainable modes of transport and reduce car usage. This paper investigates the effect of personal and transit characteristics on travel choices of TOD users. Binary logistic regression models were developed to determine the probability of choosing sustainable modes of transport including walking, cycling and public transport. Kelvin Grove Urban Village (KGUV) located in Brisbane, Australia was chosen as case study TOD. The modal splits for employees, students, shoppers and residents showed that 47% of employees, 84% of students, 71% of shoppers and 56% of residents used sustainable modes of transport.

Microscopic modelling of freeway operations

Freeways are divided roadways designed to facilitate the uninterrupted movement of motor vehicles. However, many freeways now experience demand flows in excess of capacity, leading to recurrent congestion. The Highway Capacity Manual (TRB, 1994) uses empirical macroscopic relationships between speed, flow and density to quantify freeway operations and performance. Capacity may be predicted as the maximum uncongested flow achievable. Although they are effective tools for design and analysis, macroscopic models lack an understanding of the nature of processes taking place in the system. Szwed and Smith (1972, 1974) and Makigami and Matsuo (1990) have shown that microscopic modelling is also applicable to freeway operations. Such models facilitate an understanding of the processes whilst providing for the assessment of performance, through measures of capacity and delay. However, these models are limited to only a few circumstances. The aim of this study was to produce more comprehensive and practical microscopic models. These models were required to accurately portray the mechanisms of freeway operations at the specific locations under consideration. The models needed to be able to be calibrated using data acquired at these locations. The output of the models needed to be able to be validated with data acquired at these sites. Therefore, the outputs should be truly descriptive of the performance of the facility. A theoretical basis needed to underlie the form of these models, rather than empiricism, which is the case for the macroscopic models currently used. And the models needed to be adaptable to variable operating conditions, so that they may be applied, where possible, to other similar systems and facilities. It was not possible to produce a stand-alone model which is applicable to all facilities and locations, in this single study, however the scene has been set for the application of the models to a much broader range of operating conditions. Opportunities for further development of the models were identified, and procedures provided for the calibration and validation of the models to a wide range of conditions. The models developed, do however, have limitations in their applicability. Only uncongested operations were studied and represented. Driver behaviour in Brisbane was applied to the models. Different mechanisms are likely in other locations due to variability in road rules and driving cultures. Not all manoeuvres evident were modelled. Some unusual manoeuvres were considered unwarranted to model. However the models developed contain the principal processes of freeway operations, merging and lane changing. Gap acceptance theory was applied to these critical operations to assess freeway performance. Gap acceptance theory was found to be applicable to merging, however the major stream, the kerb lane traffic, exercises only a limited priority over the minor stream, the on-ramp traffic. Theory was established to account for this activity. Kerb lane drivers were also found to change to the median lane where possible, to assist coincident mergers. The net limited priority model accounts for this by predicting a reduced major stream flow rate, which excludes lane changers. Cowan's M3 model as calibrated for both streams. On-ramp and total upstream flow are required as input. Relationships between proportion of headways greater than 1 s and flow differed for on-ramps where traffic leaves signalised intersections and unsignalised intersections. Constant departure onramp metering was also modelled. Minimum follow-on times of 1 to 1.2 s were calibrated. Critical gaps were shown to lie between the minimum follow-on time, and the sum of the minimum follow-on time and the 1 s minimum headway. Limited priority capacity and other boundary relationships were established by Troutbeck (1995). The minimum average minor stream delay and corresponding proportion of drivers delayed were quantified theoretically in this study. A simulation model was constructed to predict intermediate minor and major stream delays across all minor and major stream flows. Pseudo-empirical relationships were established to predict average delays. Major stream average delays are limited to 0.5 s, insignificant compared with minor stream delay, which reach infinity at capacity. Minor stream delays were shown to be less when unsignalised intersections are located upstream of on-ramps than signalised intersections, and less still when ramp metering is installed. Smaller delays correspond to improved merge area performance. A more tangible performance measure, the distribution of distances required to merge, was established by including design speeds. This distribution can be measured to validate the model. Merging probabilities can be predicted for given taper lengths, a most useful performance measure. This model was also shown to be applicable to lane changing. Tolerable limits to merging probabilities require calibration. From these, practical capacities can be estimated. Further calibration is required of traffic inputs, critical gap and minimum follow-on time, for both merging and lane changing. A general relationship to predict proportion of drivers delayed requires development. These models can then be used to complement existing macroscopic models to assess performance, and provide further insight into the nature of operations.