DEADWEIGHT ANCHORS 



A. Anchor Types 



Vary from: sophisticated (concrete/steel anchors with cutting 

 edges) to engine blocks, concrete clumps, etc. 



Added capacity from sophiscation must be balanced against cost. 



(a) Sinker 



(b) Squat clump 



(c> Railroad rails or 



(d) Concrete slab with 



(c) Open frame with 







scr^ iron 



shear keys 



weighted comers 



efficient uplift 



• low overturning 



• low bulk, high 



• high lateral capacity 



• high lateral capacity 



easy to handle 



• more area con- 



weight 



• scour control 



• reduced lowering line 





tacting soil 



• low cost 





dynamic tensions 

 • shallow burial 



(g) Wedge 



» shallow burial 

 I low overturning 

 > nni-directional 



(h) Slinted skirt (i> Hi^ lateral capacity, 

 fieefaU 



I deeper burial 

 > uni'directional 



• free fall installation 



• high lateral capacity 



» free fall installation 

 » efficient uplift 



Several variations on the basic deadweight anchor. 



B. Design Procedures 



1. Simple Form (anchors w/o 

 shear keys) 



Idealized deadweight 

 resists lateral load 

 component by static 

 friction; vertical load 

 resisted by portion of 

 anchor wt. 



Net normal force, R , 

 n 

 contributes to lateral load 



resistance, R. , according to: 



h = 



M R 



Pandunemil Cooecpt of Desdwci^i Andior. 



Where [i is the coefficient of friction between anchor block and 

 seafloor; \i varies w/seafloor type/strength. 



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