The RCRC’s comprehensive plan to develop Riyadh road network included development of King Abdullah Road, which extends 25 km from King Khalid Road in the west, to Sheikh Jaber Al-Ahmad Al Sabah Road in the east. The development program aims to transform King Abdullah Road from an arterial road to a freeway and a key nerve of metropolitan activities.
The Royal Commission for Riyadh City divided King Abdullah Development Project into four phases:
|From west intersection of Prince Turki bin Abdulaziz Al Awwal Road to east intersection of King Abdulaziz Road
|Saudi Oger Limited
|From east intersection of King Abdulaziz Road to east intersection with Khalid bin Al Walid Road
|Almabani General Contractors
|Phase 3 (A)
|From east intersection of Khalid bin Al Walid Road to west intersection of Sahabah Road
|Al Fahd Contracting Company
|Phase 3 (B)
|From west intersection of Sahabah Road to west intersection of Sheikh Jaber Road
|Al Fahd Contracting Company
|From east intersection of King Khalid Road to west intersection of Prince Turki bin Abdulaziz Al Awwal Road
|Almabani General Contractors
This phase extends 5.3 km from west of King Abdullah Road’s intersection with Prince Turki bin Abdulaziz Al Awwal Road to east intersection with King Abdulaziz Road. The work sphere in this phase includes building three tracks in the main road and two tracks in the service road in each direction, which increases near the main intersections, entrances and exits. During this phase, the median was reserved to host a Riyadh Metro Line.
King Abdullah Road’s comprehensive development plan set the following design objectives for the first phase of the project:
To highlight the esthetical aspects of the project, the RCRC added architectural formations to create a rich and harmonious visual environment. The esthetical elements included covering walls of the tunnels, asphalting pedestrian walkways and parking areas using special materials that highlight beauty of the road. In addition, design of the parks and gates, landscaping, and lampposts makes travelling along the road both entertaining and safe.
The project took all measures necessary for environment protection by providing the pedestrians with integrated environment and reducing the vehicles’ pollutant emissions. Moreover, more green areas were added and the road was kept at the ground level, in addition to building tunnels at intersections instead of bridges.
For the first time in the Kingdom, a new material made of recycled tires were used in asphalting the road to absorb noise and alleviate the possibility of slips during rains. Of course, this helped in ridding of the damaged tires by reusing them in manufacturing this material.
Frontage roads were designed parallel to the main road to provide access to shops and houses. This measure contributed to the smoothness of traffic movement along the road, and promoted the role of local service roads in urban uses at both sides of the road and the neighboring districts. Therefore, more service lanes were added near intersections, entrances, and exits of the main road.
The 15-meter median was allocated for a double-track metro line (Red Line). The RCRC has developed a comprehensive plan for public transport in the city that includes establishment of a public transport network for busses and metro.
The project included establishment of three 185-meter tunnels at the road’s intersections with Turki Bin Abdulaziz Al Awwal Road, Al-Takhassusi Road, and King Abdulaziz Road, in addition to a fourth 700-meter tunnel extending from west of King Fahd Road to the east of Al-Olaya Street.
The design of these tunnels considered the functional requirements necessary for traffic smoothness, emergency responsiveness, as well as the other safety, maintenance and operational requirements.
Likewise, the esthetical aspects were also considered through covering walls of the tunnels with fiberglass plates with rocky colors to mimic the natural appearance of the rocky formations familiar in this area of Riyadh.
The project’s main tunnel, linking King Fahd Road and Al-Olaya Street, extends for 700 meters to provide high traffic smoothness and a suitable environment for pedestrians thanks to its gardens and walkways.
To ensure optimum performance, the tunnel was equipped with many safety and security systems in addition to emergency services to keep it always ready for dealing with the changing circumstances. The systems include early warning system, and automatic anti-fire system in addition to power generation system to serve as alternative during possible power outages. The tunnel was also provided with light guides that work in case of lack of vision to guide the drivers to the safe exits on both sides of the tunnels. The tunnel is also equipped with engineering fixtures to evacuate the vehicles facing any troubles. The traffic management systems also include cameras and guiding signs.
To ensure smooth and sufficient airflow into the tunnels, ventilation fans were used to push the air along the traffic direction in both sides, and they can be reversed in case of fire to increase efficiency of firefighting. The main tunnel was provided with an anti-fire system that comprises early warning system (sensors), fixed and mobile firefighting points, and guiding light at the emergency entrances and exits of the tunnel.
To drain rainwater, collection pools were built to receive rainwater and then send it to a reservoir. After that, the collected rainwater is pumped into the sewer network using powerful pumps with a capacity of 194 liters/second. Emergency units were also used and the tunnel was provided with a reservoir that separates water from oil derivatives that may leak from the vehicles.
The tunnels were equipped with 4250 different normal and reserve units for emergency cases. The lighting units are divided into units used during the daylight and units used at night. The daytime lighting units produce intensive light at the two ends of the tunnel to be consistent with the lights outside it. The tunnel was also provided with LED units to identify the two sides of the road and ensure the safety of the tunnel users in cases of emergency.
Following its development, King Abdullah Road provided an open environment for pedestrians characterized by safety and complete isolation from vehicles. The Road was also equipped with the suitable fixtures including the seating areas scattered along the walkway, different services, functional and aesthetical lights, intensive afforestation on both sides of the road, taxi parking areas, and public busses.
The walkway extends for about 10 kilometers on both sides, and its width ranges from 4 to 12 meters to accommodate the pedestrians and shoppers in the vicinity and the metro and public busses users. The necessary preparations to serve the people with special needs were taken, and suitable barricades were used to prevent cars from using the pavements.
To identify the two ends of pedestrian walkways at the intercessions with the road, automatically-controlled LED lights are used to give green light to the pedestrians when the traffic lights are red and vice versa.
Along the pavement, sixteen 6-meter-high shadowed waiting areas are distributed to suit the pedestrian needs and they were equipped with concrete seats. In addition, 19 parking areas were allocated for bus and taxi stops near the waiting areas.
In order to maintain the number of the stops along the road and prevent the illegal parking, the stops were designed with an angle of 45 degrees and supplemented by a space of 1.5 meters for detouring and leaving the parking area. A number of these stops were dedicated to the people with special needs.
The roofs of four tunnels were transformed into open areas including green spaces, public arenas and, later, the main entrances of metro stations. The purpose was to make these areas serve as green lungs for inhabitants of the neighboring districts as well as passengers. The parks also added an environment-friendly touch to the road in particular and the city in general. Meanwhile, they worked on connecting both northern and southern sides of the road architecturally, and facilitate the movement of the shoppers and make it safer.
With a total area of 19,000 m², the parks comprise paved areas and green spaces that serve metro passengers and current pedestrians who move between the two sides of the road. Natural rocks were scattered at the borders of the parks to define and separate them from pedestrian areas. They were placed and lined up randomly to provide seating areas for people.
To complete the aesthetical and environmental touch, the gardens and squares were provided with fountains to alleviate high temperatures, in addition to installing two symbolic red gates in every garden to identify the areas the pedestrians can use to log into the open spaces and parks, in addition to their aesthetical value as prominent landmarks along the road.
About 53,000 trees and shrubs were planted in the vicinity of the road and at its different elements to decrease the environmental pollution resulting from the vehicles’ emissions in addition to providing a suitable environment for pedestrians. The afforestation becomes intensive near the green areas, which were equipped with an irrigation network that is controlled by radio waves. The parks are irrigated using the groundwater accumulating around the walls of the tunnels, which are collected in artesian wells to be treated using a reverse osmosis treatment unit with a capacity of 1750 m³/day.
About 215 13-meter-high lampposts were used in lighting the main road. The lampposts are spaced at 40-meter intervals, while the service roads were lit using 508 8-meter-high lampposts spaced at 20-meter intervals.
At the intersections, eight 25-meter-lampposts were used at each intersection, totaling 32 lampposts, while the pedestrian walkways were lit using 730 4-meter-high lampposts. About 1051 lighting units were used on top of the palm trees, while the parks, squares, intersections and tunnels were provided with aesthetical lighting units.
A new network was established along the road to drain the floodwater and another channel to drain the groundwater, while the problem of water accumulating near the tunnels was solved through complete isolation of the foundations, in addition to using treated concrete characterized by resistance to water, salts and sulfate.
The project introduced advanced technological traffic management applications to take advantage of the road’s full capacity and improve traffic safety. The applications included variable-message signs, and integrated traffic guiding system along the service road, in addition to automated traffic monitoring system at intersections and along the road with surveillance cameras and control system for entrances and exits.
This system is run via central control room that provides drivers with live updates about traffic congestion and accidents. This system would be used later in all roads of Riyadh and the Kingdom.
On Sunday, 26 Jumada II, 1432H (May, 2011), HRH Prince (now King) Salman bin Abdulaziz Al-Saud, former president of the Royal Commission for Riyadh City, paid an investigative visit to King Abdullah Road Development Project and inaugurated some parts of the road after completion of the median development works from west intersection of Prince Turki bin Abdulaziz Al Awwal Road to east intersection of King Abdulaziz Road.
A giant project like King Abdullah Road, with such influence on the metropolitan traffic movement and commercial/residential activities, requires taking many things into account. Accordingly, this was reflected in the project’s plan, design and development strategy that focused on ensuring continuity of the traffic movement and keeping the commercial activities in the vicinity unaffected during implementation.
The construction of the tunnels and opening of the intersections before traffic movement northward and southward were scheduled to ensure continuity, smoothness and safety.
Regarding the main road and its tunnels, tunnels at intersections with King Abd Al Aziz Road, Al Takhassusi Road, and Prince Turki bin Abdulaziz Al Awwal Road were completed first to allow use of these intersections in traffic movement northward and southward. The preliminary studies developed a set of alternatives to achieve this purpose, and the RCRC choose the best in handling the road’s architectural circumstances, traffic size and temporary side effects. The strategy’s focus was on completion of the tunnels at the main intersections as early as possible to be opened before traffic movement.
As for the service roads, they were implemented in a way to avoid blockage near the commercial areas. The service road was divided into sections and each section was completed in two phases to allow use of the open section for movement and parking near the commercial facilities.
With regard to the areas with no commercial facilities, the service road was blocked and traffic was diverted to the neighboring roads.
Given the road’s strategic location in the commercial heart of the city and its role as a key link between eastern and western sections of the city, it was extremely necessary to take care of the traffic movement during the different implementation phases. Therefore, at the early stages of the project, the RCRC conducted comprehensive studies on alternatives and traffic diversions with the help of specialists in the field of traffic engineering and in coordination to the Riyadh Traffic Department. The alternatives focused on keeping the impact of works on the traffic movement within the minimum limits by working first on the tunnels and the main road, while postponing the works of the service road to a later phase to overcome traffic obstacles.
In this respect, the RCRC carried out an integrated set of traffic diversions for each intersection equipped with all traffic safety requirements and the concrete barricades to define the lanes. They were also provided with instructional, informative and warning signs designed according to the highest engineering standards, in addition to special lampposts.
All fixtures were tailored and manufactured specifically for the project to suit the conditions of the road traffic and the commercial facilities overlooking it.
Although the traffic at King Abdullah Road was high even before the project, the traffic diversions improved the smoothness of the traffic movement to the extent that there was no need for traffic lights at the main intersections throughout the project.
The preparations and reconstruction of the public service lines, whether those parallel to the road or intersecting with it, required much planning, coordination and maintenance. The work required transference and restructure of public utilities and service networks serving the adjacent districts, which interfered with the road’s construction works. This included the flood drainage lines, sewer network lines, ultra voltage power grids, whether those serving the adjacent districts or the neighboring governorates, phone lines, and water network lines, including an 800-mm line at the intersection with Al-Olaya Street that provides Riyadh residents with fresh water.
The project’s key engineering challenge was implementation of a tunnel beneath the bridge of King Fahd Road, which overpasses King Abdullah Road. The challenge was to implement the tunnel beneath the intersection without closing the bridge before traffic movement (more than 280,000 vehicles/day).
Indeed, the consolidation of the bridge represented a serious challenge, but it also was a great achievement that helped in avoiding closure of the bridge, a decision that would have negatively affected the whole metropolitan traffic.
The bridge bases fall only 1.5 meters away from the two sides of the tunnel to be implemented. The bridge columns were supported and its load was transferred to a group of piles on the sides and central section of the bridge to support the bases of the columns carrying the bridge.
The diggings at the project site amounted to 1.5 million m³of soil. This mission required dividing the digging sites and deploying the largest possible number of the digging machines.
The main challenge that faced that digging process was the intensive traffic especially during the rush hours, which required working around the clock and postponing transference of the earthed soil to their locations at the times of low traffic.
The intensive and continuous traffic at the service passageways represented high pressure over the main tunnel, which required supporting it particularly during rain seasons.