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▪ I. ˈoverˈburden, n.
Also † -burthen.
[over- 29 d, 1 d.]
1. Excessive burden; excess of burden.
1579–80North Plutarch (1657) 42 The vitall spirits not being..kept downe, or spreade abroad by the quantity or over-burden thereof [meat], do enlarge themselves. a1618Sylvester Job Triumphant iv. 440 Who hath dispos'd the upper Spouts and Gutters, Whereby the Aire his over⁓burthen utters? 1893Daily News 8 Feb. 5/1 The overburden of work in the House of Commons makes the effort to get real business done a mere struggle and scramble.
2. Mining, etc.
a. The overlying clay, rock, or other matter which has to be removed in quarrying or mining, in order to get at the deposit worked.
1855J. R. Leifchild Cornwall Mines 25 The quantity of ‘overburthen’, or waste, removed, has been upwards of 200,000 tons. 1894Times 27 Feb. 10/3 The overburden is a reddish clay soil of an average depth of 10 ft.
b. The material lying over any particular point underground, esp. over a tunnel or pipeline; also, the pressure due to the weight of this material.
1948Terzaghi & Peck Soil Mech. in Engin. Pract. ii. 68 With respect to the present overburden, the clay on the right-hand side is a precompressed soft clay, and that on the left-hand side is a normally loaded soft clay. 1968G. N. Smith Elem. Soil. Mech. iv. 88 The overburden pressure at a point in a soil mass is simply the weight of the material above it. The effective overburden is the pressure from this material less the pore water pressure. 1970Daily Tel. 27 June 2/5 The pipeline was laid in December 1967..but the unexpectedly heavy scouring action of the bottom waves in the shallow North Sea soon removed the two foot overburden.
c. Loose, unconsolidated material lying above bedrock.
1955Proc. Colorado Sci. Soc. XVI. 102/1 Overburden,..a term used by geologists and engineers in several different senses. By some it is used to designate material of any nature, consolidated or unconsolidated, that overlies a deposit of useful materials, ores, or coal, especially those deposits that are mined from the surface by open cuts. As employed by others overburden designates only loose soil, sand, gravel, etc., that lies above the bedrock. The term should not be used without specific definition. 1969Civil Engineering (U.S.) June 43/2 A more detailed soil investigation of the upper 50 ft or so of the overburden..showed that the allowable bearing capacity was only about 200 to 300 psf, much too low for the proposed bridge foundations.
▪ II. ˌoverˈburden, -ˈburthen, v.
[over- 27.]
trans. To put too great a burden or weight upon; to burden too much; to overload, overcharge.
1532More Confut. Tindale Wks. 824/1, I neither wil for so plain a matter ouerburdein the reader in this boke, with the..rehersyng of euerye place. a1584Montgomerie Cherrie & Slae 1041 The waik anes that oreburdenit bein. 1725Pope Odyss. xi. 379 The earth o'erburthen'd groan'd beneath their weight. 1726Leoni Alberti's Archit. I. 56/1 To avoid over-burthening the Arch. 1881Raymond Mining Gloss., Overburden,..to charge in a furnace too much ore and flux in proportion to the amount of fuel. 1885Spectator 25 July 976/2 Mr. Leland does not overburthen his..myths and legends with comment.
Hence ˌoverˈburdened, -ˈburthened ppl. a.; ˌoverˈburdening, -ˈburthening vbl. n. and ppl. a.; whence ˌoverˈburdeningly adv.
1713C'tess of Winchilsea Misc. Poems 240 The Miser..fears the *over-burthened Floor. 1871–4J. Thomson City Dreadf. Nt. ix. ii, The hugeness of an overburthened wain.
1580Hollyband Treas. Fr. Tong s.v. Affaissement, A shrinking vnder a great burthen, an *ouerburthening.
1851R. Nesbit in J. M. Mitchell Mem. xii. (1858) 303 Mr. James Mitchell's *overburdening duties.
1865Mrs. Whitney Gayworthys xxiii, Not officiously or *overburdeningly; there were kindnesses accepted, even asked for, in return. |