New Road Construction Concepts
This is just a short post highlighting EU’s vision for 2040. It attempts to build reliable, green, safe, smart, and human infrastructure and the vision is outlined in the document commonly known as NR2C. Read more by following the link New Roads Construction Concepts.
Most underground services need to be accessed to carry out repair and maintenance works. They can be accessed through manholes, which consist of a vertical shaft allowing a person to get into a chamber below ground level. The type and size of manhole depends on the type of action required for repair and maintenance works to the service. Each entity has its own requirements for its own manhole.
Manholes can be divided into two categories:
Step 1 : Determine the Size of the Manhole
A manhole is a link between an underground service and the surface above it, through which the service can be accessed and maintained.
The size of a manhole depends on:
Shallow manholes come in two sizes:
Step 2: Determine the Type of Construction
Shallow manholes can be constructed in block work, in-situ concrete, pre-cast concrete chambers, corrugated galvanised steel chambers. In this post we will be showing manholes constructed in blockwork and in-situ concrete.
Step 3: Excavate Terrain for Manhole Structure
After determining the minimum dimensions, excavate terrain for manhole and allow an extra 230mm on either side of the pipe for the manhole walls. The depth of excavation shall be a minimum of 150mm below invert level to allow for manhole foundations.
If the surface on which the foundation shall be placed is rock, then the surface has enough bearing capacity to construct the manhole structure. The surface shall be swept from debris and large stones.
If the surface is unbound material, then the surface shall be wetted and compacted using hand compactors.
Step 4: Lay reinforced concrete foundation
Lay A393 reinforcement mesh top and bottom as shown in the diagram. Use concrete spacers to minimum of 40mm cover around the mesh.
When you are ready to lay the concrete, wet the surface and pour a minimum of 150mm thick layer of C20 concrete (also known as ST4 concrete), up to the invert level of the pipe.
Type A Manhole
Step 5: Constructing the concrete walls
When the foundation concrete has set, lower the steel formwork into position. Make sure that there is a space of 230mm between the steel formwork and the exposed rocky face to ensure that the manhole walls are thick enough. Use an A393 mesh around the steel formwork ensuring that there is at least 40mm cover and adequate lapping, shaped into a rectangular shape. Cast the C20 concrete between the steel form and the exposed rock, up to road formation level and vibrate the concrete.
Type B manhole
Step 6: Formation of benching
C10 concrete shall be used to form the benching next to the sides of an open channel as per above-drawings.
Step 7: Roofing the manhole
The manhole shall then be roofed using a pre-cast concrete slab, consisting of 180mm thick C20 concrete with A393 mesh top and bottom, having an opening of 600x600mm.
The orientation of the manhole roof shall be in line with road features such as kerbs etc.
Other Tips:
Step 7: Selection of manhole cover
Classification of Manholes as per EN124
Manhole covers shall be specified according to European Standard EN124, which classifies manhole covers into 6 groups, according to their intended use ranging from class A15 intended to be used in pedestrian areas only to F900 which are intended to be used in freeports and airports. Class A15 manhole covers can withstand 15kN while F900 manhole covers can withstand 900kN.
Manhole covers should be properly installed as per manufacturer’s recommendations to ensure that they perform satisfactorily. For more details you can follow the link below:
Shifou Mountains - Click on the image for the complete set of photographs.
I wonder if there are any Health & Safety Authorities in China. Who is going to check if these employees have all the required harnesses and minimum Personal Protective Equipment, while they are constructing a footpath along the vertiginous slopes in Shifou Mountains? 
I do not know if they have the minimum PPE but they sure must have nerves of steel.
AJ McCormack’s authoritative website offers in depth, well researched information and clear diagrams describing the proper installation of concrete block paving. Topics include:
Should you know of any other websites about concrete paving blocks, please share it by writing the link in the comments below.
Valletta Road, Zurrieq
Client: Transport Malta
Supervisor: Edwin Mintoff & Associates
This project was started in January 2010 and had to be completed within 36 weeks.
The Valletta Road Zurrieq Reconstruction project consisted in the laying of new services such as sewer mains, potable water mains, 6 way duct routes for telecommunication cables, Enemalta cables and a storm water network. The road was completely rebuilt. It includes reinforced C30 concrete hard shoulders on both sides. Crash barriers and new street lighting were also installed. A reservoir was built for storm water harvesting.
The project was completed on budget and ahead of schedule.
05.02.2010 Valletta Road to be completed by August 2010
27.07.2010 Valletta Road re-opened to traffic within budget and ahead of schedule
29.07.2010 The Valletta Road Project is completed to high standards and ahead of schedule
San Lawrenz Road
Client: Ministry for Gozo
Supervisor: iAS Ltd.
Works on the 3km long stretch from Victoria, next to the Pope John Paul II monument, to San Lawrenz was carried out in 2006. Works were successfully carried out by MACjv, a joint venture between Schembri Infrastructures Ltd, Bonnici Brothers Ltd and Road Construction Company Ltd.
This road forms part of arterial road 1 forming the backbone of the road network of Malta. It is used by visitors to Ta Pinu Sanctuary and to Dwejra. Water mains, sewer mains, electrical cables and telecommunication duct routes and a 1.8m high walk through service culvert were installed. Mass masonry walls were also built along the road.
19.3.2006 Ministers tour works on San Lawrenz road
03.09.2006 Extensive Road reconstruction Projects in Gozo
Hal Far Road - Phase III
Client: Transport Malta
Supervisor: EMDP Ltd.
This project was started in December 2005 and completed slightly ahead of schedule in December 2006. The project consisted in the re construction of Hal far road from Lyster Barracks roundabout to the Freeport Terminal at Birzebbuga. The road alignment was improved and dangerous curves were eliminated. The project included a considerable amount of new mass masonry retaining walls cladded with rubble walls. New potable water mains, sewer mains, electrical cables and telecommunication duct routes were installed. A storm water pipe was also laid to collect storm water runoff.
11.12.2005 Reconstruction of Hal Far Road kicks off
17.12.2006 Hal Far road re-opened to traffic