10/15/2016. Building stones

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1 Building stones Introduction to the use of building stones Requirements for building stone Standards Geology and geological classification of rocks according to EN

Natural stones Dimension stones Building stones Dimension stone Natural stone or rock selected and finished to specific sizes or shapes - sliced, cut, drilled, ground, or other - color,

2 Natural stones Dimension stones Building stones Dimension stone Natural stone or rock selected and finished to specific sizes or shapes - sliced, cut, drilled, ground, or other - color, texture and pattern, and surface finish durability - Endurance and capability to maintain its essential and distinctive characteristics of strength, resistance to decay, and appearance 2

The major producers:brazil, China, India, Italy, and Spain, 9-20

S, 2007 U.S. dimension stone production was 1.

tons valued at $106 million I($ 233/ton) limestone 493,000 tons valued

3 million ($189/ton) One of the oldest forms of business

com/wordpress/wpcontent/uploads/2012/03/oldest-structures-megalithic

3 The major producers:brazil, China, India, Italy, and Spain, 9-20 Mtons/year, each Portugal produces 3 Mton/year USGS, 2007 U.S. dimension stone production was 1.39 million tons valued at $275 million, granite production was 453,000 tons valued at $106 million I($ 233/ton) limestone 493,000 tons valued at $93.3 million ($189/ton) One of the oldest forms of business temples4.jpg Main use of building stones Foundation and Wall Items Facing and Architectural Items cladding materials slabs and stones, stairs and landings, parapets etc. Building Items: Elements of stairs, landings, parapets and guard rails 3

4 Road Construction Items Curb stones intended to separate roadways from sidewalks; Paving blocks used for pavements; Cobble stone used to reinforce slopes of earth works and banks of water basins armored stones 7 Bridges and underground structures Slabs and stones typically from igneous and sedimentary rocks 8 4

silicious stones Resistance against alkalis.

5 Heat and Chemically Resistant Items Non-weathered rocks. For high temperature working conditions, - chromite, basalt, andesite and tuffs - protection against acid - granite, syenite, and silicious stones Resistance against alkalis. - Limestones, dolomites, marble and magnesite show excellent 9 Qualities of building stones Architectonical, esthetics Appearance and structure Physical properties Economic Cost of production and transportation Market demand Uniform and homogeneous rocks with predictable properties and appearance 10 5

6 Stength function of mineralogy, macro- and microtexture Weight density of most common minerals (and many rocks) ton/m 3 porosity (proportion of vugs, cavities, microfractures) For certain structures such as dams, retaining walls, etc. heavier stones are used arches, vaults, domes, etc. light stones may be the choice 11 Weight density of most common minerals (and many rocks) ton/m 3 porosity (proportion of vugs, cavities, microfractures) For certain structures such as dams, retaining walls, etc. heavier stones are used arches, vaults, domes, etc. light stones may be the choice 12 6

7 Hardness function of mineralogy, macro- and microtexture typically measured using Mosh-scale (average) mineralogical composition Dory s testing machine Measurement of rocks important for floors, pavements, aprons of bridges, etc. Grinding resistance, skidding in pavements and floors 13 Toughness The measure of impact that a stone can withstand Resistance to vibratory or moving loads For toughness A steel hammer of 20 N is allowed to fall axially in the specimen. The blow at which the specimen breaks represents the toughness of the stone. 14 7

8 Porosity and Absorption - Primary porosity e.g. in volcanic rocks depends on the composition, cooling time and - Secondary porosity most pores in sedimentary rocks are secondary (dissolution of cement) microfractures - Water can fill the pores by Infiltration, capillary suction, chemical bonding i.e. absorption - In cold conditions water freezes, expands, and causes cracking - Water enables chemical reactions and weathering dissolves minerals, transports dissolved constituents by advection and diffusion - Permissible water absorption for some of the stones is given in Table EN 1936 NATURAL STONE TEST METHODS. DETERMINATION OF REAL DENSITY AND APPARENT DENSITY, AND OF TOTAL AND OPEN POROSITY apparent density (ρb) o ratio between the mass of the dry specimen and its apparent volume apparent volume o volume limited by the external surface of the specimen, including any voids volume of the solid part o difference between the apparent volume of the specimen and the volume of the voids (open and closed pores) real density (ρr) o ratio between the mass of the dry specimen and the volume of its solid part open porosity o ratio (as a percentage) between the volume of the open pores and the apparent volume of the specimen total porosity o ratio (as a percentage) between the volume of pores (open and closed) and the apparent volume of the specimen 16 8

Relevant standards [1] EN 1925, Natural stone test methods Determination of water absorption coefficient by capillarity. [2] EN 1926, Natural stone test methods Determination of compressive strength.

[5] EN 12372, Natural stone test methods Determination of flexural strength under concentrated load. [6] EN 12407, Natural stone test methods Petrographic examination.

9 Relevant standards [1] EN 1925, Natural stone test methods Determination of water absorption coefficient by capillarity. [2] EN 1926, Natural stone test methods Determination of compressive strength. [3] EN 12370, Natural stone test methods Determination of resistance to salt crystallisation. [4] EN 12371, Natural stone test methods Determination of frost resistance. [5] EN 12372, Natural stone test methods Determination of flexural strength under concentrated load. [6] EN 12407, Natural stone test methods Petrographic examination. [7] EN 12440, Natural stone - Denomination criteria. [8] EN 13161, Natural stone test methods Determination of flexural strength under constant moment. [9] EN 13364, Natural stone test methods Determination of the breaking load at dowel hole. [10] EN 13373, Natural stone test methods Determination of geometric characteristics on units. [11] EN 13755, Natural stone test methods Determination of water absorption at atmospheric pressure. [12] EN 13919, Natural stone test methods - Determination of resistance to ageing by SO2 action in the presence of humidity. [13] EN 14066, Natural stone test methods Determination of resistance to ageing by thermal shock. [14] EN 14146, Natural stone test methods Determination of the dynamic modulus of elasticity (by measuring the fundamental resonance frequency). [15] EN 14147, Natural stone test methods Determination of resistance to ageing by salt mist. [16] EN 14157, Natural stone test methods Determination of the abrasion resistance. [17] EN 14158, Natural stone test methods Determination of rupture energy. [18] EN 14205, Natural stone test methods Determination of Knoop hardness. [19] EN 14231, Natural stone test methods Determination of the slip resistance by means of the pendulum tester. [20] EN 14579, Natural stone test methods Determination of sound speed propagation. [21] EN 14580, Natural stone test methods Determination of static elastic modulus. [22] EN 14581, Natural stone test methods Determination of linear thermal expansion coefficient

EN 14231 Slip resistance test by pendulum apparatus 19 Geology of building stones Main types of rocks Igneous, Sedimentary,

substances with a crystal lattice Texture - The size, shape, and arrangement of the grains (for sedimentary rocks) or

10 EN Slip resistance test by pendulum apparatus 19 Geology of building stones Main types of rocks Igneous, Sedimentary, Metamorphic The key controls of physical properties rocks Mineralogy - Minerals comprise rocks - Naturally occurring substances with a crystal lattice Texture - The size, shape, and arrangement of the grains (for sedimentary rocks) or crystals (for igneous and metamorphic rocks) - Microscopic to macroscopic features Structure - Large scale features (outcrop, megascale) 20 10

rocks (hard, crystallization of magma in deep bedrock) Volcanic (lava

Pyroclastic deposits and rocks (products of explosive eruptions of

11 Igneous rocks a.ka. Magmatic rocks Magmatic rocks Intrusive rocks a.k.a. plutonic rocks (hard, crystallization of magma in deep bedrock) Volcanic (lava flows produced by eruptions of magma) Intrusive dikes and sills Also: Pyroclastic deposits and rocks (products of explosive eruptions of magma that have deposited directly without sedimentation and reworking cycles) 21 Igneous rocks Kuva: GTK/Paavo Härmä Page 22 11

12 Volcanic rocks Most magma erupting on the surface as lava flows is basaltic Andesites comprise smaller lava flows Dacites and rhyolite lavas much less common Relation of pyroclastics is opposite! Why? Explosive eruptions 12

13 Dykes - Represent intrusion channels for magma - Cooled faster than intrusive rock but slower than volcanic rocks Page 25 Sedimentation processes Transport by Water, wind, mass-flows, glaciers Deposition as clastic or chemical sediments Sedimentary cycle Stratified bedding x-bedding lamination graded bedding Massive 26 13

14 Sedimentary rocks Sediments and clastic sedimentary rocks Rounding of grains Transport distance and mechanisms Multiple cycles possible Sorting of grains Depositional mechanism Cement Transforms a sediment to sedimentary rock Cement: e.g. granular, prismatic Matrix: microcrystalline matter, mainly deformed and recrystallized grains 14

Sandstones Silica gel comprising hydrous, amorphous SiO 2 and a common cement in sandstones leads to alkali reactions within (manmade) portland-cement-pastes inducing serious damage to concrete

Mudstones Shales are one of the common building stones Mudstones (and their low-degree metamorphic equivalents) can be extremely difficult in terms of geotechnical properties - Disintegration when

15 Sandstones Silica gel comprising hydrous, amorphous SiO 2 and a common cement in sandstones leads to alkali reactions within (manmade) portland-cement-pastes inducing serious damage to concrete Quartzite and quartz sandstone comprising crystalline SiO 2 (quartz) is hard and durable material that commonly comprises excellent aggregates (but can be difficult to drill or excavate)! Mudstones Shales are one of the common building stones Mudstones (and their low-degree metamorphic equivalents) can be extremely difficult in terms of geotechnical properties - Disintegration when exposed to air and rain spalling - Low plasticity and liquid limits - Erosion - Expandable clay minerals Expand when dry clay is wetted Also in wet clay if composition of water changes and induces ion exchange (Na to Ca) On the other hand: BGS was established in 1832 to map mudstones and shales that could be excavated easily Construction of channel system to Devon, UK 15

Non-clastic sedimentary rocks Carbonate rocks Evaporites (particularly

evaporite-karst geohazards in Great Britain A. H.

1007/s00254-007-0724-8 Metamorphosis (Complete) recrystallization due

metamorphosis Driven by tectonic processes (deformation) Contact

16 Non-clastic sedimentary rocks Carbonate rocks Evaporites (particularly challenging for construction) Phosphorites The GIS approach to evaporite-karst geohazards in Great Britain A. H. Cooper, Environ Geol (2008) 53: ,DOI /s Metamorphosis (Complete) recrystallization due to changes in temperature and pressure or temperature Regional metamorphosis Driven by tectonic processes (deformation) Contact metamorphosis Driven by magmatism New mineral assembly No changes in overall chemistry Adding or removal of fluids (water, carbon dioxide) 16

17 Deformation and metamorphosis leads to anisotropism Gneisses and migmatites however, have higher strengths than schists Retrograde metamorphosis and alteration along shear planes: particularly potential zones of shear failure Classification of rocks examples 34 17

18 Igneous rocks A field method for macroscopic observation A standard method based on microscopic studies EN 12670:2001 Classification of volcanic rocks EN 12670:

19 Pyroclastic rocks Based on volcanic clasts Composition (SiO 2 ) 19

sandstones Classification based on grain size (clast size) The

21 Mudstones Shale: fissile tecture Mudstone preferable used when massive Marl= clay +fine carbonates 41 Field classification of sandstones Classification based on grain size (clast size) The following is based classification by Dickingson (1978) For macroscopic studies 21

22 Carbonate rocks 43 Limestone classification 44 22

23 Metamorfic rocks Simplified field classification (For the following not included terms: eclogite, granulite, leptite, migmatite, ophicalcite, phyllite, serpentinite, see 3.1.) 46 23

24 47 Compton: Geology in the Field 24

Wikipedia.org BUILDING STONES. Chapter 4. Materials of Construction-Building Stones 1

Wikipedia.org BUILDING STONES. Chapter 4. Materials of Construction-Building Stones 1 Wikipedia.org BUILDING STONES Chapter 4 Materials of Construction-Building Stones 1 What is Stone? Stone is a concretion of mineral matter. Used either as a; Construction material, Manufacture of other