Four million passengers in 2016: this is the growth forecast for the Rafael Núñez airport in Cartagena de Indias according to SACSA, the concession company. Majority-owned by the Spanish company Aena Internacional, in 2011 SACSA embarked on a project to improve and expand airport facilities, both on ground and in the air, in order to adapt airport capacity to the growing demand. Ineco recently updated the airport’s Master Plan which plans for expansion work until 2020 and has also designed and coordinated construction work (see IT48). Five years ago, work began on passenger terminal building renovations and expansion; work then continued on the design and surveillance of work on the runway, aprons, the perimeter road and the new FBO terminal for general aviation services.

The increase in traffic at the airport is associated with the tourism and industrial activity in this city –located on the coastline of the Caribbean Sea–, whose characteristic, walled historic quarter has been a UNESCO World Heritage Site since 1984. The city stands out as a domestic holiday destination, and although the number of international arrivals has increased, the majority of the city’s air traffic is mainly domestic with connections to the capital, Bogotá, as well as to main cities such as Medellín and Cali. In terms of international flights, top destinations include southern Florida in the United States in addition to Chile, Venezuela and Spain.

In order to drive the tourism sector, the airport operator and local entities such as Corporturismo and the Cartagena City Council are committed to implementing additional long-distance routes both to North America –the city’s main source of outbound tourism– and to Europe –especially to Germany and Spain. Airlines are thus operating larger aircrafts, in turn requiring airports to provide greater capacity as well as increased safety and security –both operational and physical. Since all work must be carried out without interfering with airport operations, Ineco also conducted a study on the different stages of construction in order to minimise the effects as much as possible.

Greater passenger and aircraft capacity

Thus, the construction work that was carried out at Rafael Núñez airport met these requirements: the current terminal building which was expanded from 2011 to 2013 has grown from 10,491 m² to 19,370 m². Expansion of the international hall is currently under way. The runway in addition to the main and secondary (or ECO) aprons were repaved between 2013 and 2014 to repair damaged areas and to increase their load bearing capacity. The axis of the turnaround area was modified to make it easier for large aircrafts to move around, and signalling and traffic guidance equipment was also improved.

With regard to the runway, Ineco designed and coordinated the installation of an asphalt mix that had never before been used in Colombia: a discontinuous, BBTM-11 bituminous mixture (with additional fibres) in a 4-cm screed used on 1,740 metres of the runway’s 2,540 total metres. The asphalt not only improves friction conditions on the wearing surface, but it also facilitates drainage and prevents hydroplaning.

On both aprons, a P-401 bituminous hot mixture with a maximum aggregate size of ¾” was used with a BMIII modified asphalt, with varying thicknesses of 5 to 12 centimetres. The landing gear stop-way was also reinforced with 33-cm concrete slabs. Since there are fewer demands with regard to reinforcements on the perimeter road and pedestrian areas, a MDC-2 bituminous hot mixture with B60/70 asphalt was installed.

General aviation on the rise

In addition to the aforementioned interventions which are of vital importance in terms of aircraft safety, the increase in general aviation traffic was kept in mind. Private and military flights represent more than 90% of traffic at this airport, while the remaining percentage is represented by executive flights, school flights, etc. Although general aviation represents less than 1% of the total passengers who use this airport, it corresponds to 30% of airport operations and is expected to grow an average of 3.9% by 2020, totalling some 26,000 passengers and 14,000 operations.

Therefore, construction work was carried out on a new FBO general aviation terminal in 2014 (Fixed Base Operator, a company from the United States in this case), as agreed upon in the draft that had previously been drawn up by Ineco. The new terminal, located in the eastern part, boasts three different areas: airport authority, border control and entry/exit of passengers and baggage; a surveillance area that covers access areas both to and from air and ground, as well as security checkpoints; and a passenger waiting area.

The project included the construction of a new, stand-alone building with an electrical substation, a hydraulic pump room and a drinking water supply in addition to a handling office. Shared with the secondary apron, a new perimeter road was also constructed with direct access from Vía del Mar, the road that connects Cartagena de Indias with Barranquilla.

The growth forecast predicts that Rafael Núñez airport will see four million passengers in 2016

Ongoing work

Rescue and fire fighting services (RFFS) are fundamental elements when it comes to increasing an airport’s capacity. Aeronautics and airline regulations require that the capacity of these services must be rigorously determined by the size (total length and fuselage width) of the aircrafts that normally operate at the airport. Therefore, airports are categorised on a scale of 0 to 10; Rafael Núñez airport falls into category number 7, meaning that this airport would need a minimum of two fire-fighting vehicles, one fire chief and four firefighters.

Nonetheless, the new facilities designed by Ineco provide for the possibility, also foreseen in the regulations, of increasing these resources if, with prior notification, the airport needed to occasionally accommodate aircrafts corresponding to higher categories. For this reason, airport sheds have space for four vehicles: three fire engines and one light-weight commanding vehicle.

Seeing as this airport operates 24 hours a day, the RFFS requires staff to cover three shifts; thus, the new building has the appropriate facilities for said staff to rest in addition to offices, warehouses, technical areas and a car park. In front of this building there will be a paved clear zone that will allow for aircrafts to transition to the military area. Additionally, there will be two water deposits each containing 30,000 litres of water supply for the fire engines, and said fire engines will also be provided with a new access road, thus facilitating their arrival to the runway in under three minutes. Ineco is overseeing the construction work and is also monitoring compliance with the Operational Safety Plan.

Another ongoing project coordinated and monitored by the company includes the enlargement of the runway safety strip; in some areas, this strip does not meet the required distance of 75 metres between the runway axis and the border of the airport. To meet this requirement, ground is being gained from the area of vegetation by reinforcing it with 5-metre long micropiles.

The renovation work is part of the comprehensive restoration project drawn up by Ineco in 2008 which sought to remedy shortcomings while remaining consistent with the historic character of the architecture. These large, riveted iron structures were built as a result of the Industrial Revolution during the 19th century and are epitomised by the Eiffel tower. Spain lagged a bit behind other cities with regard to the use of iron in architecture and engineering as can be seen in countless examples from Paris, London, Amsterdam, Belgium and Germany in addition to Boston and New York in the United States.

With all of this, transport infrastructure in 19th-century Spain such as stations, bridges and viaducts requiring versatility, luminosity, spaciousness and low prices were easily adapted to the engineering of iron which was best received by engineers of that time period as well as by architects. Examples of riveted iron infrastructures in Spain include the Atocha and Delicias railway stations, the Catalonia Railway Museum, the Valencia railway station and the Aranjuez railway station –the main feature of this article. Furthermore, some quite representative buildings include Sabatini’s Royal Firearms Factory in Toledo and the Geological and Mining Institute of Spain, in addition to bridges and viaducts such as the prominent Triana Bridge.

Spanish transport infrastructure in 19th-century such as stations, bridges and viaducts requiring versatility, luminosity, spaciousness and low prices were easily adapted to the engineering of iron

Aranjuez station is one of the most characteristic vestiges of the industrial age of the 19th century. The earliest railway facilities at Aranjuez were built in 1851 for the line connecting Madrid with Alicante, popularly known back then as the ‘Tren de la Fresa’ (The Strawberry Train) and whose name is now in use once again for tourist services. This station also provides service to the C3 Madrid-Aranjuez commuter rail line. It is the second oldest railway line in Spain (the oldest is the Barcelona-Mataró line, 1943) and is one of the monuments of the Royal Sites of Aranjuez, a Unesco World Heritage Landscape Site since 2001. This line originally reached all the way to the Royal Palace. The original station faced towards the palace on grounds of the company’s prestige and the fact that they needed support from the monarchy. Nevertheless, this location caused so many problems affecting train traffic that it became necessary to build a new station with a completely different layout. The platform marquees are living proof of the iron beams and framework –signs of progress from that time period– that were used to construct public buildings such as stations, markets, factories, libraries and bridges.

The technique of riveting

The steel marquees, roofed by fibre cement and fluted glass, were built around 1851 to provide shelter over the station’s three platforms which were later renovated around 1980 in order to adapt them to the trains and general regulations at that time. As can be observed in the images, the marquees suffered from corrosion problems that affected their structural framework, foundation and ornamentation due to an unsatisfactory roof water drainage system, thus causing damage to the suspended wooden ceiling and corroding the metal. Rehabilitation and restoration of these marquees was a year-long, painstaking process that rediscovered the traditional technique of riveting.

Riveting is the process of joining together several metallic pieces (metal sheets and/or profiles) using rivets. Rivets are elements that are similar to screws –but without the thread– consisting of a cylindrical shaft called a shank or the body, and a head normally shaped like a spherical cap, such as the rivets utilised for the marquees at Aranjuez station. These rivets are manufactured from ductile, malleable and durable metals such as copper, aluminium, some alloys and mild steel, such is the case with the rivets presented herein.

Riveting is the process of joining together several metallic pieces using rivets –elements similar to screws but without the thread- consisting of a cylindrical shaft and a head

To join together metal pieces made from steel, rivets are used –also made from steel– whose quality and characteristics can vary. Holes are drilled just once, piercing through two or more pieces, after having assembled, clamped and tightly screwed said pieces together. Once the holes have been drilled, the pieces are separated from each other in order to eliminate metal scrap, remnants and sharp edges from the surface. The diameter of the holes, save for exceptional cases, is made 1 millimetre larger than the diameter of the body of the rivet. Selecting the length of the body of the rivet is very important: after the rivet is placed in a furnace and uniformly heated to a temperature between 950 and 1,050 ºC in order to allow for its moulding, the riveting process is carried out by introducing the heated rivet into the hole on the pieces which are to be joined together. The body of the rivet should be cast and forged in order to form the shop head of the rivet. This piece must completely fill the hole. To form the shop head, either a riveting machine applying uniform compression is utilised, or a pneumatic hammer with a riveting pin or a bucking bar is used, always held steadily in place. These tools –not the direct strike of a hammer– are used to form the rivet’s second head. Both the furnace and the riveting machine need to be located close to the area where the riveting is to take place so as to avoid significant cooling of the rivet before it is set into place. The pieces that are joined together must lie perfectly flush and tight against each other to ensure a union without bending or warping. Afterwards, the rivet is introduced into the pieces that are being joined together, and the body of the rivet is forged. This process is carried out using a pneumatic hammer and a bucking bar on the spherical head of the rivet.