APPLICATION OF- ASPHALT IN HYDRAULIC 

 ENGINEERING WORKS 



by 



J. H. van der Burgt 



JORE8TORD 



The following translation was furnished the Beach 

 Erosion Board by the author following a recent visit to 

 the United States, It is published here to acquaint 

 American engineers vath Butch progress in the use of asphalt 

 mixtures for shore protection works. The paper has been 

 abridged to permit publication in the Bulletin. The 

 opinions and conclusions expressed are those of the author 

 and not necessarily those of the Beach Erosion Board. 



Introduction 



The extensive application of synthetic asphalt in road con- 

 struction work started around 1923? whereas it took another ten 

 years before this material was applied to any extent in hydraulic 

 engineering works. This is caused by the fact that the almost 

 horizontal road surface encased by the shoulders, was ideal for 

 testing the new and rather unstable material, whereas the sloping 

 surfaces of hydraulic works were highly unsuitable for this purpose. 



The share of the Netherlands in the research work regarding 

 the application of asphalt in road construction and hydraulic works, 

 has been appreciable. Extensive research done by the Rijkswegen- 

 bouwlaboratorium at Scheveningen and the Research Laboratory of the 

 Royal Shell at Amsterdam, combined with thorough testing and ob- 

 servation during the execution of 5 3phalt~works have led to such 

 control of the properties of asphaitic bitumen and bituminous 

 mixtures, that now it is possible to use this very durable product 

 appropriately on sloping surfaces, even on steep slopes. 



Asphaitic Bitumen and Bituminous Mixtures 



The asphaitic bitumen is derived to a snail extent from 

 natural sources and synthetically made on a large scale. 



The well known natural asphalt from Trinidad is a rather 

 impure product, which is unfit for use in hydraulic works, as the 

 enclosed clay-particles are affected by water. 



The synthetic asphaitic bitumen is derived from petroleum. 

 The remaining product becomes harder as more oily components are 

 evaporated during the process of distillation. 



^Composed after a lecture, given by the author on 10 Bee 1948 for 

 guests and members of the V.B.W. (Association of Bituminous Works) 



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