New Access Carriageways to the Inter-island Terminal (Las Palmas)
The construction work on this Project comprises the creation of new access carriageways to the inter-island terminal as well as the urbanisation of its surroundings. The new carriageways will be set out in the following manner:
Street 1 has a roundabout at either end, one at the intersection with Andrés Perdomo Street (existing roundabout) and the other at the intersection with Streets 1 and 2 (Roundabout 1). This street is eighty-eight metres and twenty centimetres (88.20 m) long and twenty-three metres (23 m.) wide. One side of the carriageway has two four-metre (4.00 m) wide lanes and the other side has one four-metre wide (4.00 m) lane. Two metres seventy centimetres (2.70 m.) wide parking spaces and two metres and eighty centimetres (2.80 m.) wide pavements are projected for both carriageways which will increase to five metres fifty cm. (5.50 m.) width at the accesses to the roundabouts.
Street 2 has a roundabout at each end, one at the intersection of Streets 1 and 2 (Roundabout 1) and the other at the intersection of Streets 2 and 3 (Roundabout 2). This street is two-hundred and eighty-two metres and thirty-eight centimetres long (282.38 m.) and twenty-three metres (23 m.) wide. In one direction, the carriageway has two four-metre (4.00 m.) wide lanes and the other side has a single four-metre wide (4.00 m.) lane. Two metres seventy centimetres (2.70 m.) wide parking spaces and two metres and eighty centimetres (2.80 m.) wide pavements are projected for both carriageways which will increase to five metres fifty (5.50 m.) width at the accesses to the roundabouts.
Street 3 begins at Roundabout 2 and runs until the beginning of the exit ramp. Its length is ninety-three metres and sixty-five centimetres (93.65 m) and the width twenty-seven metres (27 m.). It has two four-metre wide lanes (4 m.), one in each direction with five metre fifty (5.5 m) wide pavement on each side.
Roundabout 1 is at the intersection of Street 1 and Street 2. The outside radius of this roundabout is twenty-nine metres and sixty centimetres (29.60 m.). Roundabout 2 is the intersection of Streets 2 and 3 and its radius is twenty-nine metres 60 centimetres (29.60 m.).
Both roundabouts comprise two lanes which are four metres fifteen centimetres (4.15 m.) wide and the pavement is five metre fifty cm. wide (5.50).
The pavement is bordered by a 50×15-18×30 cm bevelled concrete kerb and is paved with grey hydraulic tiles in four cuts, sized 25×25 cm. Tapered ramps are foreseen in the areas where the zebra crossings will be installed, in compliance with accessibility regulations.
The roundabouts shall be carried out with prefabricated concrete containment kerbs in “Drago” style, sized 45x49x45 cm.
Gravity Sewer Networks
The sewer system network has two gravity collectors with a diameter of 315 mm. made in corrugated polyethylene, which run down the middle of the carriageways. This network starts at the curve located in Street 2 and the discharge outlet is into the sewage collectors accessing the sewage pumping plants, at Roundabouts 1 and 2.
Sewage connections to the plots, made of D-250mm corrugated polyethylene pipes from the manholes at the pavement kerbs have been designed and they discharge into the sewage basins and the intention is to offer service to all plots.
The gravity flow network includes manholes approximately every 50 metres, to which the plots will be connected. These sewage pipes will be connected to the manholes in each roundabout which in turn will be connected to the pumping stations foreseen in each one.
The gravity flow network consists of a high-density corrugated polyethylene sewage pipe, three-hundred and fifteen mm. in diameter (Ø 315 mm.) in two layers, an outside one in black and corrugated and an inside one in white and smooth, with elastic joints and special parts necessary for their installation. Buried in a trench on a 10 cm. thick sand-bed and protected by sand with a 15 cm covering above the centre of the pipe, the rest of the grid will be completed with an aggregate filling.
Sewage Impelling Networks
Because the discharge point of the sewage network is higher than the level of the new carriageways, two sewage impellers are to be installed to collect and pump the sewage, to collect it from the gravity flow and pump it to the connection point. Therefore, two impeller networks are being carried out.
Impeller Network number 1 connects the pumping station located on Roundabout 2 with the pumping station on Roundabout 1 and Impeller Network number 2 connects Pumping Station number 2, connecting the Pumping Station located on Roundabout number 1 with the existing general network (at the already existing roundabout at Andres Perdomo Street).
The impelling networks will be installed with molecularly oriented PVC pipes (PVC-O) 110mm in diameter, with a nominal pressure of 16 atm.
Two prefabricated Ø1100 mm. GRP pumping stations will be installed, 3000 mm. high, built in fibreglass with an average thickness of 5 mm. on the lateral walls and 7mm on the bottom and top parts. Equipped with its general collector built in AISI 316L, DN 080 with an outlet to the DN 080 PN-10 flanged tank and two separate PVC PN16, DN 065 branches for each one of the pumps, ready to connect to each one of the pump’s discharge elbow joints, even including guide bars to hoist the pumps, a support to hang the hoisting chains, a lid for access to the inside of the tank also made in pressed polyester equipped with a closing system, anti-reflux valves and a hatch. The tank is prepared for an inlet connection of DN 150-300 and an adequate impeller outflow connection.
Two submersible motor pumps with a number 214 impeller, 1.7 kw grinder type motor at 2.700 RPM, triphasic 380 V, 50 Hz will be installed, with cabling through to the connection point.
The pressure network will be made of PVC oriented at 16 atm, DN-110mm, placed at the bottom of a trench on a 10 cm thick sand bed and protected by mountain sand up to 10 cm. above the channelling top surface, including the special parts, levelling of the pipe, sand to cover the pipe and filling and compacting the remaining channelling with selected soil.
You can see the details of said network in Plan number 12, Sewage Network
Rainwater Collection System
The draining of both streets is done by means of a fibreglass reinforced concrete continuous channel one hundred and sixty millimetres (160 mm.) wide with a D-400 ductile iron grate, placed next to the kerbs in the lower point of the pumping network of the streets.
These channels are connected every 50 metres to filter wells distributed along the complete network and which have a filter base made of 40 to 70 mm. gravel on which a settling base of concrete is made to support the rings of the prefabricated wells.
In Plan Series 13, Rainwater Network, you can see details of the entire network.
Water Supply Network
The water supply mains network to be installed in the pavement of the new streets is composed of two mains according to the number of users it will be providing water to and is described as follows: Ship supply network – a network comprising an FD Ø250 mm. mains running along the pavement on the west side. This mains system is undertaken on Andres Perdomo Street: right after the connection, a mains control unit is carried out which will be connected to an existing water mains at Roundabout 2 and the supply mains to the plots, comprising FD Ø100 mm. mains running along the pavement on the east side. This mains is carried out on Andres Perdomo Street and then runs along the pavement with connections to the different plots along it, until it reaches the vicinity of Roundabout 2 where it ends in a blind flange. Before the mains comes to an end, a purge-drain mains has been installed, the outflow of which drains into the rainwater system for mains maintenance.
In Plan number 14: Water Supply Network, the details can be seen.
The connection of this service to the roundabouts and plots has been set out by means of pipes from the distribution connection manholes.
The civil works necessary to supply this service will be carried out. The channelling and manholes necessary have been installed in the pavement with the following characteristics:
– Installation of the following channelling:
a) 4 Ø110 mm PVC pipelines;
b) 1 PE Ø63 mm tritube
– Type D Connection manholes placed at the beginning and end of the Project and street intersections and Type D Passage manholes placed every 50 m. or at the change in alignment.
– Connections to plots by means of mains from the inspection manholes.
In Plan Series number 15, Telecommunications Network, you can see the layout and details of said network
Low Voltage Network
The necessary civil works will be carried out to provide supply to the plots. For this, the following must be done:
– Installation of two Ø200 mm. corrugated PE pipes.
– Type 3 Connection manholes installed at the beginning and end of the Project area and inside the roundabouts and Type 2 passage manholes, placed every 50 m. or at the changes in alignment.
– Connection to plots by means of pipes from the inspection manholes.
In Plan Series Number 16 Low Voltage Network, you can see the mapping out and details of this network.
The necessary civil works have been completed for the installation of the streetlighting along the streets, carrying out the following:
– Installation of channellings of PE Ø110 mm. corrugated pipes;
– A3 type connection manholes placed at the beginning and the end of the Project and within the roundabouts and street intersections;
– Foundations of the posts for the street lights;
– Passage and Inspection Manhole to connect all the streetlamp posts.
In Plan Series Number 17 Streetlighting Network, you can see the layout and details of this network.
Conforming to what is set out in Regulation 6.1 C Sections of Road Surface and given that the type of ground is tolerable soil and the esplanade is Type E2, we conclude that the esplanade ought to be covered with a layer of select soil of around 100 centimetres thick. With these figures, a section formed by 0.25 m. of artificial rubble and 0.25 m. of bituminous mixture has been set out.
Keeping these thicknesses in mind, and as set out in the Spanish Road Construction Regulations PG3 in Articles 542 and 543, the section of the surface on the carriageways is set out as follows:
a) 0.10 m of AC32 base B50/70 G
b) 0.10 m of AC22 bin B50/70 S
c) 0.05 m of AC16 surf B50/70 D
You can see the development of the calculations in Attachment number 5, Calculations of the Road Surfacing.
The Project also includes the marking and painting of all the horizontal traffic signs as set out in the plans as well as vertical signs by means of the installation of vertical sign-posts made in steel sheets following the regulations set by the Ministry of Public Works of Spain.
Vertical signposts will be placed in spots where they will not interfere with pedestrian crossings and can be visible from all carriageways.
Street signage can be seen in detail in Plans Series Number 17: Signage.