Pavement structure - Articles and news items
Issue 5 2010 / 1 October 2010 /
Fiumicino is the ‘hub’ airport for domestic, international, and intercontinental scheduled and charter flights. Ciampino, conversely, is the airport city dedicated to the low cost traffic, goods traffic of ‘express courier’ and to the General Aviation. (more…)
Issue 2 2008, Past issues / 28 March 2008 /
From its dedication in 1999, the National Airport Pavement Test Facility (NAPTF), of the U.S. Federal Aviation Administration (FAA), has been tasked with conducting research on both rigid and flexible airport pavements. The facility offers a unique opportunity to study, instrument and record full-depth soil and pavement interactions under a variety of test parameters.
Pavement experiments can be performed over three different subgrade soil strengths as measured by California Bearing Ratio (CBR): Low Strength (CBR 3-4), Medium Strength (CBR 7-8), and High Strength (CBR 25-30). Of particular interest to NAPTF engineers, are the load interactions which occur from multiple-wheel landing gear on a given pavement structure. To date, research conducted at the NAPTF has been instrumental in developing refined design procedures that provide more reliable predictions of pavement life from aircraft traffic. (more…)
Issue 5 2007, Past issues / 28 September 2007 /
Until recently, the primary interest in measuring and evaluating the properties of airport pavement surface profiles has been, at least in the US, in characterising the vertical geometry and the smoothness of newly constructed pavements.
Federal Aviation Administration (FAA) acceptance criteria for these pavement properties are contained in Advisory Circular AC 150/5370-10B, ‘Standards for Specifying Construction of Airports.’ For grade control, the as-constructed grade must not deviate from the design grade by more than 12 mm (0.5 inches) at any point on the surface. For smoothness, the maximum deviation from a 4.9-m (16-foot) straightedge must not exceed 6.4 mm (0.25 inches) at any location on the pavement. Optionally, a California-type profilograph may be used with a sliding scale for payment, although the straightedge requirement is not waived in cases where there is a conflict between the two types of measurement. (Consult AC 150/5370-10B for the complete specifications and see AC 150/5300-13, ‘Airport Design,’ for the vertical geometry requirements.) Experience has shown that, when the pavement has been properly designed and construction meets the grade and smoothness tolerances stated above, the resulting pavements are safe for aircraft operations with regards to accelerated gear load damage, airframe fatigue damage, pitch and roll motions, and accelerations experienced in the cockpit. (more…)
Issue 3 2007, Past issues / 3 April 2007 /
After a 10-year research and development effort, the Federal Aviation Administration (FAA) is set to debut a new software package for airport pavement thickness design. The new program is called FAA Rigid and Flexible Iterative Elastic Layered Design, but is known by its acronym, FAArfield. In addition to putting the finishing touches on the FAArfield software, the FAA is also substantially rewriting the Advisory Circular (AC) covering Airport Pavement Design and Evaluation (AC 150/5320-6D). The revised AC will make FAArfield the FAA’s standard thickness design procedure for both rigid and flexible pavements, including overlays, and will retire the FAA nomograph-based design procedures. (more…)
Issue 4 2006, Past issues / 1 December 2006 /
Unforeseen operational delays related to pavements are not acceptable for airport authorities. This and limitations in the available funds and resources, as well as the strong need felt by the decision makers to qualify and to quantify the consequences of allocating budgets to maintenance, has led to the situation where use of a pavement maintenance management system is a must for airport authorities. (more…)
Issue 1 2006, Past issues / 17 March 2006 /
In preparation for the increasing introduction of heavy aircraft and new types of landing gear (e.g. B777 and A380), AIRBUS, STBA and LCPC undertook an ambitious research programme to define a more efficient pavement design method. (more…)
Issue 4 2005, Past issues / 25 November 2005 /
A report from this year’s European Pavement Workshop from the organisers.
Prof. André Molenaar opened the workshop by noting that the current workshop is, in fact, a European continuation of the three former Dutch workshops organised by CROW. Interest in this workshop was high, considering that just over 100 people from all over the world were participating.
The most interesting topics will be briefly described in this article. The first keynote speech was by Ray Rollings, a military pavement engineer with over 30 years of experience on the (un)expected deterioration of military and civil airport pavements. Ray pointed out that problems with materials and construction are more profound than those related to pavement design. Nowadays 30-ton wheel loads with 2.4 MPa tyre pressure are no longer the exception.
Cyril Fabre of Airbus started by showing a video of the A380-800 maiden flight cycle. The images were quite impressive. The distance of the runway needed for take-off was between 1 and 1.5 km, although the plane was not at max. take-off weight. (more…)
Issue 3 2005, Past issues / 16 September 2005 /
The next generation of aircraft creates new pressures for an airport’s pavements, consequentially engineers at the FAA’s Research and Development centre are continuing to develop systems to predict and assess requirements.
In 1927, the Ford Motor Company built one of the world’s first paved runways at Ford Airport in Dearborn, Michigan. With no aviation experience and no airport pavement design specifications, engineers built this and other early runways using pavement thicknesses similar to those of early highways. In fact, until World War II, airport engineers based concrete pavement design on the anticipated loads imposed by the trucks refuelling the airplanes, rather than the airplanes themselves.
For many years after the war, airport pavement research and technology benefited from advances in highway research, as well as from Department of Defense research supporting military aircraft and airfields. “Added complications in today’s design estimates stem from the facts that aircraft weigh far more than they did when the basic relationships were established and that landing gear layouts are far more complicated, with many more wheels per gear and more gears per aircraft,” explains Dr. Gordon Hayhoe, Manager of the FAA’s National Airport Pavement Test Facility. (more…)
Issue 2 2005 / 10 June 2005 /
For an operator such as BAA, innovation in engineering and design starts from the ground up, with its runways future-proofed by TPS Consult.
The growth of air passenger traffic in the UK has been phenomenal and there are no signs that the rate of increase will abate. Far from it, projections show that expansion will continue apace. The main airports all have enlargement schemes at varying stages of planning, but even with those being implemented, there may still be capacity problems during the next two decades. With all this new development, the construction and aviation sectors are set to be very busy!
BAA owns and runs key airports in the UK including Heathrow, Gatwick, Stansted, Southampton, Edinburgh, Glasgow and Aberdeen. It also has interests in a number of airports overseas (Indianapolis, Boston, Pittsburgh, Naples, Perth and five other airports in Australia) with more than 200 million passengers passing through its airports each year. BAA is pivotal to the aviation industry in the UK and is instrumental in a number of the expansion plans that are proposed around the country. (more…)