A new process for the structural plate analysis has been presented that is based on the condition of stationarity of total complementary energy (equilibrium model) instead than on the condition of the stationarity of the total potential energy (con-gruence model) as usually done. Each of the two processes, asregards to...
Some Theoretical and Practical Aspects of the Use of Fly Ash in Lean Concrete
Until a few years ago, interest in the incorporation of fly ash into lean concrete was rather limited. A study conducted in the laboratory has demonstrated some of the advantages of the technique and shown that the optimum dosage is of the order of5 %. In Belgium, mixtures of this...
Optimization of Surface Characteristics of Cement Concrete Roads
The surface properties of a road pavement must fulfill a long list of requirements. Recently this list has been extended to include acoustic properties. Roughness is characterized by micro-, macro- and megatexture. The results of measurement of skid resistance and road-tire noise are discussed. Possibilities for further optimization of the...
The Use of Seismic Tests to Assess the Properties of Portland Cement Concrete During Curing
«In situ» measurements of surface wavevelocityon two prototype concrete slabs indicate that seismic measurements offer a reliable alternative to con-ventional penetration resistance and cylinder com-pression tests for determining the stiffness of Port-land cement concrete during curing. The surfacewave velocity was determined using a nondestruc-tiveand nonintrusive technique called the SpectralAnalysis of...
The Use of Steel Fibre Reinforced Concrete in Heavy Duty Port Pavements
Recent years have witnessed a considerable growth in importance of heavy duty pavements, mainly because of several major pavement failures in ports leading to serious problems. A recent development took place in the concrete technology and has considerably increased the cost effectiveness and performance of concrete heavy duty pavements making...
The Asturias Motorway Balance of Its First 15 Years Under Traffic
The Asturias motorway, called «y» -asturiana, links the three most important cities in Asturias. It has 43 km of continuously reinforced concrete pavement and was built during 1974and 1975.The behaviour of the motorway up to now has been very good in spite of the rainy weather and the unfavourable geology....
Problems of the Reconstruction of Motorways in the Gdr
The 1860 kilometre GDR motorway network was mainly built in concrete slab construction before 1945. Its overall reconstruction is vital. In the course of reconstruction work a number of different paving variants were put into practice. The covering of unbound and nearly impermeable bases needed the drainage of the intermediate...
RCC Applications in Low-Volume Roads in Spain
The first known applications of RCC pavements in low-volume roads in Spain took place around 1969-1970. They included pavements located on housing developments, urban streets and rural roads. These applications have been increasing until now, when the technique is used in different parts of Spain and in other countries (Norway,...
The New Spanish Standard on Pavement Design
The General Highway Plan (1984-1991) currently under execution has prompted an overall update of the specifications, in order to take into account the past experience, the new materials and the traffic evolution since 1975. In general, internally vibrated portland cement concrete pavements (PCCP) for heavy traffic have transverse joints every...
Lime-Cement Stabilization of Wet Cohesive Soils
When treated with lime, wet cohesive soils granulate and be-ome more workable, thus allowing easier subsequent incor-oration of cement.'he effects of pregranulation with lime on various aspects ofement stabilization were investigated: compaction. CBR bear-19 capacity, strength values, durability, the effects of differentariables such as density and moulding moisture content. Theitter...
Study of Long-Lasting Materials and Conventional Paints on Concrete Surfaces
Due to the increase of concrete use in road cons-truction, the report examines the influential fac-tors on the three most important properties in roadmarking, above all on concrete pavements.The analysed properties are:- Night visibility.- Day time visibility.- Skid resistance.The study makes a comparison of two systems:two components system (plastic of...
Cement Concrete Characteristics For Road Pavements Practical Experience with the Polyfunctional Composite Pavement (Pcp)
A stretch of the slip-road between the Al and A2 (Fiano tomano-S. Casareo) has been made of PCP (polyfunctional .omposite pavement). The system is "composite" owing to the rresence of several layers: mix cemented to cement binder, :ontinuous reinforcement concrete slab and bituminous layer; 'polyfunctional" owing to the diverse functions...