THE IKKIGATION AGE. 



279 



Hollow Core Wall for Hydraulic Fill Dams 



In a Hydraulic Fill dam the prob- 

 lem of the drainage of the sluicing 

 water is of controlling importance. The 

 sluiced material should be such that 

 it will not retain the sluicing water 

 for an undue time. If the material 

 is such that it will not deliver the 

 water with reasonable rapidity a de- 

 cided settlement with consequent cracks 

 is bound to ensue when the fill ulti- 

 mately dries out. 



The sluicing water on the fill is 

 maintained in a summit pool by hand- 

 made levees. It is found that in 

 depths downwards to 5', the material 

 in suspension becomes comparatively 

 solidified and it will then hold its shape 

 and consistency. The sluicing water, 

 however, must necessarily be under con- 

 stant drainage if rapid construction and 

 solid hanks are expected. 



A Hydraulic Fill dam during con- 

 struction generally has water in the 

 impounding reservoir above it which 

 rises at substantially the same rate as 

 the increasing height of the dam, but 

 a little below its level, thereby reducing 

 the drainage head in that direction. 

 Assuming that there is no core wall, 

 the sluicing water is forced to pass 

 largely through the down stream fill 

 unless drainage tubes in some form 

 are provided. The passage of the 

 drainage water through such a mass of 

 material is slow, and hence full 9 ad- 

 vantage cannot be taken of the other- 

 wise rapid method of hydraulic con- 

 struction. 



Again, the material of the fill will 

 not take its final set until the fill is 



complete. The fill is therefore saturated during construction, and 

 saturated material is always of greater bulk than dry material. 

 This fact accounts in a measure for the excessive settlement in 

 hydraulic fills. 



All this is controlled by building a Hollow Core Wall through 

 the center of the embankment, and providing it with numerous 

 drainage gates of simple construction. A facing of broken stone 

 or gravel should be placed next to the upstream face of the 

 core wall. 



It is evident at a glance that with this construction we have 

 accomplished two things : 



First, we have provided an effectual water-barrier whereby when 

 the lower prism of the dam is once drained it is forever protected 

 against re-saturation. 



Second, the problem of drainage is entirely under control and 

 can be hastened or retarded at will. Drainage head is secured 

 in two directions, namely, towards the core and towards the toe. 

 The material more quickly receives its final set and unexpected 

 settlement is thereby avoided. The time of construction is greatly 

 hastened. 



Moreover, in the usual form of construction the levees on the 

 outside edge of the pond frequently give way and permit a 

 localized washout on the slope of the fill. The central drainage 

 into the Hollow Core Wall permits of instant relief of excessive 

 water and makes a washout impossible. 



Again, if the sluicing material is such that it settles rapidly, the 

 surface water can be quickly drawn off into the Core Wall. 



Once the fill is completed the drainage gates into the Core Wall 

 from the lower prism are permanently opened. This insures an 

 absolutely dry prism; a result never before reached. 



The above is a mere outline of the functions of the Hollow 

 Core Wall in relation particularly to the Hydraulic Fill during 

 construction. The advantages named in a previous advertisement 

 in connection with an ordinary rolled earth dam apply in full to 

 the Hydraulic Fill when the same is completed and in permanent 

 service. 



The above notes are fairly illustrated by the sectional drawing 

 herewith presented which roughly represents a Hydraulic Fill 

 Dam in process of construction. The Hollow Core Wall is car- 

 ried up to and a little above the ultimate embankment and pro- 

 vides interior inspection through the heart of the fill. 



This topic is more fully treated in our Circular on EARTH 

 DAMS. (This circular is now in preparation and will be issued 

 during the month of May.) The introduction of the Hollow 

 Core Wall entirely changes the basic problem of an earth dam, 

 whether of rolled earth or hydraulicked into place. These points 

 will not admit of discussion in an advertisement. 



Respectfully submitted, 



AMBURSEN HYDRAULIC CONSTRUCTION CO. 



ENGINEER-CONSTRUCTORS, 88 Pearl St., Boston, Mass. 



All inquiries from Canada should be addressed to 



Ambursen Hydraulic Construction Co., 



405 Dorchester St., West, Montreal, P. Q. 



HYDRAULIC FILL DAM WITH HOLLOW GOBI! WALL 

 IN PROCESS OF CONSTRUCTION. 



NOTICE OF SUIT IN INFRINGEMENT 



Notice is hereby given that on April 9, 

 1912, we brought suit in the United States 

 District Court for the Southern District of 

 New York against the Hydraulic Properties 

 Company of New York, to restrain the in- 

 fringement of our Re-issued Letters Patent, 

 1 2,246, which cover broadly the type of dam 

 now known as the "Ambursen Reinforced- 

 Concrete Dam" or otherwise as the "Hollow 

 Dam." 



For the past seven years our patent rights 

 have been generally respected and licenses 

 have been granted by us whenever conditions 

 made it impossible for us to execute the 

 work with our own force. The aggregate of 

 royalties received by us during this period, 

 and particularly within the last two years, has 

 amounted to a very large sum of money 

 much of this by pre-arrangement but a con- 

 siderable portion after the fact of infringe- 

 ment and under more or less pressure. We 

 wish it clearly understood when we execute 

 the work ourselves, no royalty, concealed or 

 otherwise, Is introduced into our charges. 



Owing to the marked success which has 

 attended the construction of the Reinforced 

 Concrete Dam by this Company, and stimu- 

 lated apparently by the belief that we were 

 indifferent to our patent rights, infringe- 

 ments in various parts of the country are 

 apparently multiplying. We therefore give 

 public notice that from this date we shall 

 vigorously defend our rights and prosecute 

 all infringers. 



THE AMBURSEN HYDRAULIC 

 CONSTRUCTION COMPANY 



88 Pearl Street, Boston, Mass. 



When writing to advertisers please mention The Irrigation Age. 



