History of Geotechnical Engineering - TU Dresden

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History of Geotechnical Engineering

Ivo Herle

Institute of Geotechnical Engineering

TU Dresden

Dresden, October 2004

Prehistory

Footprint Evolution: Ape ; human

Egyptian pyramids

Giza (2750-2500 BC)

the oldest one: Saqqara

(3rd dynasty)

Originality

great load concentrations

(Cheops: 5 000 000 t / 231 x 231 m)

≈ almost 1000 kPa

steepness of the slopes

(Cheops: 52◦, 147 m high)

Comparison of slopes

Pyramid of Cheops, great Pyramid of the Sun in Mexico

Pyramid – a pile of stones

Meidum Pyramid (2750 BC)

Pyramid cross-section (Meidum)

slope of the nucleus (steps): 74◦, external coating walls

Instability of the Meidum Pyramid

Unstable wedge ABC

(possible slip line)

– friability of the stone

– earthquakes

Dahshur Pyramid

originally planed at 60◦ slope but poor quality of the subsoil

Dahshur Pyramid – slippage in corridors

punching effect, uneven settlement ; fractures and slip

Horizontal restraint

Toe-in to rock providing horizontal restraint (Cheops Pyramid)

Kafara Dam (2600 BC)

Wadi Garawi

(30 km south of Cairo)

just after the first

pyramid of Saqqarah

imperviousness vs stability

Kafara Dam

(Schnitter, 1994)

Section of a modern earth dam

1: Upstream shell (crushed rock)

2: Clay core

3: Filter

4: Downstream shell (sand, gravel, crushed rock)

5: In situ wall or grout curtain

Egyptian caisson — Zarbiyyeh

Egyptian selfsinking caisson

(according to description)

divers needed

Temple at Eridu (Mesopotamia)

Reconstruction of Temple I at Eridu (4000-3000 BC) — Ziggurat

Ancient Mesopotamia

Eridu

Rests of Temple I at Eridu

Ziggurat of Nanna at Ur (2300 BC)

Ziggurat of Nanna at Ur (2300 BC)

Ziggurat at Aqar Quf (Aqar Auf)

Kassite Ziggurat at Aqar Auf (2100 BC) – sun-baked bricks

Ziggurat at Aqar Quf

Settlement and spreading

1 – Fill

2 – Soft soil

3 – Temenos (platform for the temple)

(Interpretation by J. Kerisel)

Reinforcement

woven reed mats

embedded in sand between bricks

(drainage)

Present adaptation:

Fill

Ancient Greece

Parthenon in Athens (about 440 BC)

Ancient Greece

Attalos Stoa in Athens (about 150 BC)

Column base

Doric order Ionic order

Underground Doric order

columns: load concentration

stylobates(orthostats):

long blocks of dressed stone

(column foundation wall)

wider foundation base

Present adaptation:

Stylobates at Delos

iron clamps:

– uniform load spreading

– prevention of dislocation

(earthquakes)

Earthquake protection

(Palace at Beycesultan, Anatolia)

Isolated footings

(Delos)

Foundations — Pergamum

three or four storage

buildings in the ’Arsenal’

Retaining walls — Pergamum

retaining wall for the terrace

of the Temple of Demeter

at Pergamum

(about 2nd century BC)

Pergamum — Model

Temple of Demeter, Pergamum

Temple of Tiberius, Pergamum

Pergamum — Fortifications

Ancient Rome

Colosseum (80 AD)

Vitruvius: De Re Architectura (On Architecture)

1st century BC

Vitruvius began as an architect and engineer under Julius Caesar.

Later he took charge of the first Augustus’s siege engines.

When Augustus died, Vitruvius retired.

Then, under Octavian’s patronage, he wrote a ten-volume account

of known technology.

He talks about city planning, building materials, and acoustics.

He explains water clocks and sundials. He describes all kinds of

pumps.

Foundations after Vitruvius

’Let the foundations of those works be dug from a solid site and to a solid base if it

can be found, as much as shall seem proportionate to the size of the work; and let

the whole site be worked into a structure as solid as possible. And let walls be built

upon the ground under the columns, one-half thicker than the columns are to be,

so that the lower portions are stronger than the higher. . . . The spaces between

the columns are to be arched over, or made solid by being rammed down, so that

the columns may be held apart.’

’But if a solid foundation is not found, and the site is loose earth right down, or

marshy, then it is to be excavated and cleared and remade with piles of alder or

of olive or charred oak, and the piles are to be driven close together by machinery,

and the intervals between are to be filled with charcoal. Then the foundations are

to be filled with very solid structures.’

Foundation after Vitruvius

Roman shallow foundations

originally sun-baked bricks and later fired bricks

foundations built of

fired earth slabs

with wooden reinforcement

however, erosion after flooding ; collapse of many buildings

Invention of concrete

concrete — from Latin ’concrescere’ = ’to grow together’

concrete cast between a formwork

in brick for foundations

1: wooden tie-bar

application: e.g. concrete raft for the foundation of Colosseum

Cofferdam after Vitruvius

How to built a double walled cofferdam to construct a pier:

”Let double-walled formwork to be set up in the designated spot,

held together by close set planks and tie beams, and between the

anchoring supports have clay packed down baskets made of swamp

reeds. When it has been well tamped down in this manner, and is as

compact as possible, then have the area bounded by the cofferdam

emptied and dried out by means of water-screw installations and

water wheels with compartmented rims and bodies. The foundations

are to be dug there, within the cofferdam.”

Cofferdam after Vitruvius

upper scene: pumping dry with wheels and drums (screw principle)

lower scene: underwater construction using stone and quicklime to drive out water

Retaining walls after Vitruvius

’A series of supplementary walls

should be built. . . to form the

shape of the teeth of a saw or

of a comb: by this means the

earth is broken up into com-

partments and cannot push on

the wall with such a great force’

Roman military roads

1: The ’statumen’ (20 to 30 cm thick): a layer of mortar over a layer of sand

(prevents underlying clay from rising)

2: The ’rudus’ (30 to 50 cm): slabs and blocks of stone with cement mortar joints

3: The ’nucleus’ (30 to 50 cm): gravel and broken stones mixed with lime to form

a kind of concrete (firm core)

4: The ’summum dorsum’: either stone slabs (4) or gravel concrete (4’) (resistent

to wear by rain and wheels)

Paved Roman road

Old China — compaction techniques

Sung Code (1103)

improvement of clayey soils:

dig out a hole, alternate layers

of stones (broken bricks) and

original clayey soil, each layer

carefully compacted

Anji bridge (China, 600 AD)

clayey subsoil, high vertical and horizontal forces (compacted backfill)

Pile foundations of bridges

Bridge of Beaugency

(earlier than 14th century)

– foundations of a pier on sand

– masonry on short wooden piles

– susceptible to scour

Pile driving

drop-hammer piling rig

hand-operated

designed by Francesco di Giorgio

(around 1450)

Difficulties of pile foundations:

pile rotting due to water lowering, horizontal loading

Venice

Venice subsoil

(depths in m)

Rialto Bridge, Venice

Rialto bridge (Venice, 1588-92)

single span of 26.4 m (designed by Antonio da Ponte)

alluvium subsoil

beneath each abutment 600 piles – 15 cm diameter, 3.3 m length (3 groups)

group effect (fewer longer piles would be more efficient)

”Tre Archi” bridge (Venice, 1688)

”Tre Archi” bridge (Venice, 1688)

technique of root piles (drilled through the masonry)

abutments founded at a shallow depth (inside small cofferdams)

piers built directly on the river bed (inside wooden caissons)

Venetian foundations

outer walls on piles

internal walls on ground preconsolidated by older buildings

Old Venice — Foundation types

Protection works of foundations

Venetian wells (underground tanks)

rainfall collection ; sand fill (support and filtration)

1: filtering sand, 2: clay, 3: natural soil

Leaning tower of Pisa (1173-1373)

Subsoil in Pisa

Annular shallow foundation

soft ground + too heavy tower ; close to limit equilibrium

Leaning history

Banana shape

Rotation

Remediation by underexcavation

Remediation by underexcavation

Tower of Saragossa (1504-1512)

inclination probably due to the

heterogeneity of the mortar

demolished in 1892 because ”it

throws too much shade onto

the shops. . . ”

Holstentor of Lubeck (1464-1478)

Load superposition

Mining

Mining techniques

after Agricola (1556)

shaft dimension 3×1 m

four-wheeled trolleys for transport

hydraulic pumps for dewatering

ventilation shafts

Tunnel shield (patented 1818)

1: prepared shield, 2: drainage sump

invented by Marc Brunel, first under-river tunnel in London, 1825-1841,

several accidents

Charles Augustin Coulomb (1736-1806)

Coulomb addressed the Academy of Science (Paris, 1773) present-

ing a modest ”essay on the application of the rules of maxima and

minima to certain statics problems relavant to architecture.” This

”essay,” printed three years later by the Academy, is the earliest

published soil mechanics theory; it started the active and passive

pressure concepts.

He served as the ”Engineer of the King” in Paris and helped the

design and construction of many structures. He needed a theory

for the calculation of lateral earth pressures on retaining walls, so

he derived one himself. He used the newly invented calculus in this

work. For this application he was awarded by being admitted to

the Academy of Science.

The friction concept was known (newly invented) at the time, and

Coulomb added the cohesion term to it. Though he didn’t write

the shear strength equation as we know it today

τ = c + σ tanϕ,

he used it almost the same way.

Coulomb worked on applied mechanics but he is best known to

physicists for his work on electricity and magnetism. He established

experimentally the inverse square law for the force between two

charges which became the basis of Poisson’s mathematical theory

of magnetism.

Coulomb contributions to soil mechanics

All results in terms of total stresses.

(Soil) Mechanics in the 19th century

1807: Thomas Young (elastic constant)

1828: A.L. Cauchy (equations of isotropic linear elasticity)

1846: Alexandre Collin (analysis of landslides in clay)

1856: H.P.G. Darcy (filtration of water through sand)

1857: W.J.M. Rankine (critical states of stress in a mass of soil,

”planes of rupture”)

1882: Otto Mohr (stress diagrams)

1883: G.H.Darwin (density-dependent friction angle)

1885: Osborne Reynolds (dilatancy)

1885: J. Boussinesq (stress and deformation of elastic halfspace)

Role of passive earth pressure

Analysis of the failure of

retaining wall at Soissons

by Poncelet, 1840

; required foundation depth

2.5 m instead of 1.4 m

Slope stability analysis (Collin, 1846)

measured profiles of slip surfaces in clay slopes ; cycloid

Undrained shear strength

Collin (1848): Investigation of effects of changes in water content

(shear strength under zero normal load)

Permeability of sand (Darcy, 1856)

Falling head experiments

Role of density (Darwin, 1883)

”No mass of sand can be put together without some history, and that

history will determine the nature of its limiting equilibrium.”

Dilatancy experiment (Reynolds, 1886)

water-saturated sand ; shearing is accompanied by volume change

if volume change is inhibited in dense saturated sand ; decrease in

pore water pressure

Modern Soil Mechanics

1911: A.M. Atterberg (water content associated with changes in

state from soild to plastic to liquid)

1916: K.E Petterson (method of slices)

1925: Karl von Terzaghi (effective stress, consolidation theory)

1936: Arthur Casagrande (plasticity chart)

1936: M.J. Hvorslev (shear strength of clay as a function of

effective normal stress and void ratio)

1936: Arthur Casagrande (critical void ratio)

1958: Roscoe et al. (critical state soil mechanics)

Classification of clay (Atterberg, 1911)

Method of slices (Petterson, 1916)

(only friction considered)

Panama Canal

Landslides at Culebra Cut (1913)

– weak clayey rocks with interbedded layers of water-saturated sand

– heavy rains

Landslides at Culebra Cut (1915)

Landslides at Culebra Cut (1915)

Embankment failure

Train accident at Weesp

The Netherlands, 1918

42 victims

Terzaghi – Compressibility test

(reconstituted samples, 1921)

Compressibility

relationship between

void ratio e

and pressure p:

a =∆e

∆p

Theory of consolidation, PES (1923)

Concluding remarks

Ancient Egypt: steep piles of stones, sliding restraint, earth dams,

caissons

Mesopotamia: large settlements, reinforcement with woven reed

mats

Ancient Greece: strip foundations for concentrated loads, iron

clamps connecting foundation blocks, retaining walls

Ancient Rome: Vitruvius - Code of Practice, concrete foundations,

cofferdams, arches behind retaining walls, roads

Old China: compaction techniques, shallow foundations for bridges

Medieval times: wooden pile foundations for houses and bridges,

non-uniform settlements of foundations on soft soils

Enlightenment: shear strength and earth pressure theory (Coulomb)

19th century: basic (soil) mechanics (Darcy, Rankine, Mohr,

Boussinesq)

modern times: cohesive soils (Atterberg, Terzaghi, Hvorslev,

Roscoe)