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Use of new road materials (industrial wastes) in mixes for sub-bases

Conf-paper-iscr

The replacement of traditional aggregates (limestone) by crushed blastfurnace slag or LD steelmaking slag in lean concrete and in cement-stabilized hardcore was investigated. The effect of adding fly-ash to mixes of the conventional type was also studied. For mixes of equal composition (in parts by volume) and equal grading (by...

Construction procedures of relevance to the type of work to be carried out

Conf-paper-iscr

The construction of concrete pavements is associated with various requirements to be fulfilled, e.g.: full-width construction stripwise construction, but extending over the full width ) e.g., construction of new cancrete roads addition of traffic lanes to existing carriageways ) e.g., on roads in use by traffic renewal of traffic lanes...

Bond characteristics for concrete overlays

Conf-paper-iscr

Even though a bonded overlay has the advanta~es such as lower cose and fewer problems in matching adjacent facilities, ic has not been used widely in Japan. The reason is that bond characteristics in concrete overlays have not been revealed and insufficient bond in con~entional techniques has caused some problems...

New developments in the construction of railway track bases without ballast

Conf-paper-iscr

The conventional form of construction for permanent way, as first conceived about ISO years ago, adopted the ballast bed for supporting the railway track from what at that time was the most economical road building method, namely, macadam. By the same token, a p:esent-day innovative form of permanent way construt~...

New concrete curing compounds and their application to road construction in Austria

Conf-paper-iscr

The curing compounds hitherto employed have not always been found satisfactory when applied to road concrete with superplasticizer, to concrete on small jobs, to concrete placed by slipforming and to cement-boundsurfacings. For this reason three new types of curing compound have been introduced, namely, compounds which - give good protection...

Thick concrete overlays in Belgium

Conf-paper-iscr

The technique of con5tructin~ thick concrete overlays is at present being greatly developed in Belgium. Three periods are to be distinguished in overlay construction in this country: 1960 to 1969: experimental phase in which 210.000 m2 of overlay was constructed; 1970 to 1977: the second phase, in which the results...

Concrete pavements without and with dowels

Conf-paper-iscr

The deformation behaviour of a transverse joint, without and with dowel bars, under the passage of a wheel, as calculated with the aid of Westergaard's formulae /1/ is represented in fig. 1. This shows that when there are no dowel bars and no aggregate interlock across the crack (efficiency index...

Retarders and their influence upon the properties of a cement stabilised soil

Conf-paper-iscr

The engineering properties of a soil-cement mix are adversely influenced by any delay between mixing and compaction. This problem is more serious in hotter climates where the initial setting period is relatively short. As a consequence of this situation, the final product often fails to meet specification requirements. A laboratory...

Experience with thin bonded cement-bound overlays in Austria

Conf-paper-iscr

In Austria bonded overlays only 35 mm thick are made using a superplasticized concrete with a wie - ratio of 0.35 . The overlay has to be moist-cured. For thicknesses of only 20 mm a special latex addition is used. For good bond the concrete is brushed vigorously with a...