In Japan, hydro-electrical power plants are existing at approximately 1,800 places, but more than a half of such plants have been used over sixty years since the commencement of operation. Water channels that lead water, taken in from head areas, to hydro-electrical power plants are called the "headrace tunnel." The...
Methods of Repair Headrace Tunnel Invert – Repair of Deteriorated Headrace Tunnel by Using Slip Form – Paver Method
Why Should Bituminous Layers Be Used Over Portland Cement Bridge Decks
The purpose of this paper is to bring to the attention of the highway community in Portugal, a methodology that allows the construction of bridge decks with Portland Cement surfaces without the need to use bituminous surface layers. This paper will present construction methods, cost benefit analysis, some of the...
Performance of Precast Prestressed Concrete Pavements Prestressed at Joints
The precast prestressed cornrele pavement (PPCP), which allows rapid execution of repair works such as these on intersections, is inasinglyuse1 these days. It contains many joints that conventionally take the form of dowel bars, which, however, are reported to be vuhierable to damage by rainwater seepage and other factors. To...
Ultra-Thin Whitetoppirig Ontarios Experience
Ultra-thin whitetopping (UTW) is one of the newest and most innovative applications of portland cement concrete. The technique entails bonding a relatively thin layer of concrete onto an existing asphalt pavement. This technique was conceived in the United States of America and the first experimental project was built in Louisville,...
Reconstruction of Bituminous Paved Rural and Urban Roads in the Federal Republic of Germany Using Mix-In-Place Recycling with Cement
Mix-in-Place Recycling with cement stabilization is an economical and environmentally friendly method for the reconstruction of damaged asphalt roads and ways. The most remarkable characteristic of this method is that the entire existing road construction material can be used again for the new road pavement. This essay contains descriptions of...
Pavement Design Procedures for New Construction and Rehabilitation with Overlay
The first part of the paper deals with the designing of rigid pavements by means of FEM. The NE10-SOILIN program uses the NE-10 finite elements composed of subelement 2D NE-10-M (tetragonal element), subelement 3D NE-I013RJCK and subsoil element. It models the Midlins slab placed on a generally multilayer structure. Under...
PCC (Paver Compacted Concrete)
FCC (Paver Compacted Concrete) is laid with conventional road payers equipped with special screeds, namely with High-Power Compaction Screeds. The main difference compared with other concrete technologies primarily used in nowadays road construction (slipform paving) is that FCC is compacted from the surface with tamping, vibrating and pressing compacting systems....
Use of Roller Compacted Concrete in Road and Airport Pavement Construction in Sri Lanka
In the quest for introducing materials and techniques of construction, the Research & Development Division of the Road Development Authority, Sri Lanka has carried out several trials and successfully constructed an airport apron, a causeway of 2km length using Roller Compacted Concrete (RCC) pavements and a road of length 0.265km....
The Importance of Continuous Slab Support and Load Transfer at Joints in the Performance of Thin Concrete Overlays
Studies on the structural performance of existing Portland cement concrete roads in South Africa (1) have shown that the traffic utilizing these roads is not the pnme initiator of structural failures. Factors such as construction, environment and slab support conditions are predominant in initiating structural failures. However, it is also...
New Composite Cement for High Early Strength Concrete
Even small repairs on roads and runways are time consuming and lead to long time obstructions. Normal cement type mortars and concretes do exhibit iallier long hardening times and are therefore, not suitable for fast track repair. Non cementitious repair materials like resin types have other disadvantages as being only...
A New Geometry of Airport Concrete Pavements
A New Geometry of Airport Concrete Pavements
The Proposed European Standard for Concrete Pavements
This paper describes the present situation of the European Standards for Concrete Pavements. They are currently in prcparation by a Working Group created within the framework of Technical Committee CEN TC 227 "Road materials". Since many of the specifications for concrete and its constituents (cement, water, aggregates, admixtures) are covered...