Proceedings e report - Firenze University Press

More documents

Recommendations

Info

NUMERICAL SIMULATION OF THE STRENGTH OF WOODEN STRUCTURES: APPLICATION TO HISTORIC PIANOFORTE Fig. 1. Historic pianofortes at the museum of Händel-Haus-Halle (a) Fig. 2. Displacements of the pin block of the pianoforte built by Johann Schmidt (a) and deformations of the pianoforte corpus (Franz Jakob Späth and Christoph Friedrich Schmahl) (b) (a) Fig. 3. Cracks at the connection between pin block and corpus (a) and within the pin block (b) 204 (b) (b)
3. Methods and models WOOD SCIENCE FOR CONSERVATION OF CULTURAL HERITAGE For the comprehensive analysis of the construction of historic pianofortes, the determination of the strength properties of the component, the loading due to stringing as well as the distribution of forces in the structure are necessary regarding climate and humidity fluctuations plus known damages. Due to the geometrically complex structure and the nonlinear material behaviour, numerical methods of structural analysis are required. One common approach of numerical simulation is the Finite-Element-Method (FEM) used in many fields in engineering and material science. The FEM is the main simulation-tool of modern structural analysis. Using the FEM, profound knowledge on the mechanical properties and predictions of the structural behaviour can be obtained without destroying the construction by experiments. The basic idea of the FEM is the division of a complex not analytically calculable structure into discrete finite elements. The load-deformation-dependency of element-types like solids, plates and bars can be described easily basing on analytical relations, energy principles and suitable material models. By assembling the finite elements, the numerical calculation of stresses, strains and deformations of the whole structure are possible, considering boundary conditions (forces and constraints) and continuity conditions on the element border. In the case of a load-dependent forcedisplacement-relationship due to e.g. nonlinear material behaviour of creeping and cracking, an iterative-incremental solution algorithm (e.g. Newton-Raphson scheme) is carried out. All mathematical functions of the FEM are formulated consistently in vector and matrix notation. With respect to the constitutive description of wooden material, models are introduced, which represent the moisture and temperature-depending anisotropic elastic material behaviour, ductile failure due to compression loading and brittle failure and cracking due to tension and shear loading. These models are already used for applications like simulation of the load-bearing behaviour of wood connections and components. An extension of the material formulations will be obtained by finding and modifying the sets of engineering input parameters for the wood species in construction of historic pianofortes. The material models are classified by the elastic, the ductile and the brittle formulation. A tensor notation is used for the following mathematical formulas to support more ready understanding in combination with a short syntax. 3.1. Elasticity The cylindrical anisotropic elastic behaviour of wood is based on the strain-energy-density function: 1 = E : C : E 2 Ψ (1) In this formulation, the elasticity tensor C includes the Young’s moduli E r , E t , E l , the shear moduli G rt , G tl , G rl and the Poisson’s ratios v rt , v tl and v rl , where the indices r, t and l stand for the cylindrical material directions of wood (see Fig. 4). With the relation E i /E j = v ji /v ij , the stress tensor: is determined. ∂Ψ S = 2 = C : E ∂E Fig. 4. Material directions of wood 205 (2)
Page 1 and 2:
Proceedings e report 67
Page 3 and 4:
Wood science for conservation of cu
Page 5 and 6:
SUMMARY Introduction ..............
Page 7 and 8:
WOOD SCIENCE FOR CONSERVATION OF CU
Page 9 and 10:
INTRODUCTION These proceedings of a
Page 11 and 12:
Page 13:
(A) MATERIAL PROPERTIES
Page 16 and 17:
SORPTION OF MOISTURE AND DIMENSIONA
Page 18 and 19:
Page 20 and 21:
Page 22 and 23:
VIBRATIONAL PROPERTIES OF TROPICAL
Page 24 and 25:
Page 26 and 27:
Page 28 and 29:
CREEP PROPERTIES OF HEAT TREATED WO
Page 30 and 31:
Page 32 and 33:
Page 34 and 35:
MEASUREMENT OF THE ELASTIC PROPERTI
Page 36 and 37:
ELASTIC PROPERTIES OF MINUTE SAMPLE
Page 38 and 39:
4. Results Young's modulus (10^4 Mp
Page 40 and 41:
PREDICTION OF LINEAR DIMENSIONAL CH
Page 42 and 43:
DIMENSIONAL CHANGE OF UNRESTRICTED
Page 44 and 45:
DIMENSIONAL CHANGE OF UNRESTRICTED
Page 46 and 47:
AGEING OF WOOD - DESCRIBED BY THE A
Page 48 and 49:
Page 50 and 51:
Page 52 and 53:
90 30 0 3,0E-03 - 2,0E 2,0E-03 - 1,
Page 54 and 55:
4. Application HYGRO-LOCK INTEGRATI
Page 56 and 57:
RESEARCH ON THE AGING OF WOOD IN RI
Page 58 and 59:
RESEARCH ON THE AGING OF WOOD IN RI
Page 60 and 61:
Xylarium Database RESEARCH ON THE A
Page 62 and 63:
AGING WOOD FROM CULTURAL PROPERTIES
Page 64 and 65:
AGING WOOD FROM CULTURAL PROPERTIES
Page 66 and 67:
STRENGTH AND MOE OF POPLAR WOOD (PO
Page 68 and 69:
STRENGTH AND MOE OF POPLAR WOOD ACR
Page 70 and 71:
STRENGTH AND MOE OF POPLAR WOOD ACR
Page 72 and 73:
PHOTODEGRADATION AND THERMAL DEGRAD
Page 74 and 75:
Page 76 and 77:
Page 79 and 80:
ROMANIAN WOODEN CHURCHES WALL PAINT
Page 81 and 82:
Page 83 and 84:
Page 85 and 86:
DISINFECTION AND CONSOLIDATION BY I
Page 87 and 88:
3. Results and discussion WOOD SCIE
Page 89 and 90:
Page 91 and 92:
Page 93 and 94:
Page 95 and 96:
Page 97 and 98:
Page 99 and 100:
Page 101 and 102:
Page 103 and 104:
Page 105 and 106:
FUNGAL DECONTAMINATION BY COLD PLAS
Page 107 and 108:
Page 109 and 110:
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
STUDIES ON INSECT DAMAGES OF WOODEN
Page 117 and 118:
Page 119 and 120:
Page 121 and 122:
TERMITE INFESTATION RISK IN PORTUGU
Page 123 and 124:
Page 125 and 126:
Page 127 and 128:
BIODETERIORATION OF CULTURAL HERITA
Page 129 and 130:
Page 131 and 132:
4. Causes of biodeterioration WOOD
Page 133 and 134:
DEGRADATION OF MELANIN AND BIOCIDES
Page 135 and 136:
Page 137 and 138:
Page 139 and 140:
MOULD ON ORGANS AND CULTURAL HERITA
Page 141 and 142:
Page 143 and 144:
Page 145 and 146:
Page 147 and 148:
Page 149 and 150:
Page 151 and 152:
Page 153 and 154:
Page 155 and 156:
Page 157 and 158: RESEARCH STUDY ON THE EFFECTS OF TH
Page 159 and 160: 4. Methodology WOOD SCIENCE FOR CON
Page 161: WOOD SCIENCE FOR CONSERVATION OF CU
Page 165 and 166: NON DESTRUCTIVE IMAGING FOR WOOD ID
Page 167 and 168: METHODS OF NON-DESTRUCTIVE WOOD TES
Page 169 and 170: WOOD SCIENCE FOR CONSERVATION OF CU
Page 173 and 174: MEASUREMENT AND SIMULATION OF DIMEN
Page 179 and 180: IN THE HEART OF THE LIMBA TREE (TER
Page 189 and 190: 3. Conclusions WOOD SCIENCE FOR CON
Page 191 and 192: 2. Materials and methods WOOD SCIEN
Page 197 and 198: 3. Chemometrics WOOD SCIENCE FOR CO
Page 201 and 202: 3. Results and discussion WOOD SCIE
Page 203 and 204: NIR SPECTROSCOPIC MONITORING OF WAT
Page 207: NUMERICAL SIMULATION OF THE STRENGT
Page 213 and 214: SIMPLE ELECTRONIC SPECKLE PATTERN I
Page 217 and 218: 5. Conclusions WOOD SCIENCE FOR CON
Page 221 and 222: Average r adiated presure field (dB
Page 223 and 224: EXPERIMENTAL AND NUMERICAL MECHANIC
Page 229 and 230: EFFECT OF THERMAL TREATMENT ON STRU
Page 235 and 236: The aims of this work are to: WOOD
Page 237 and 238: ultramarine [bad] titanium white [m
Page 239 and 240: 4. Conclusions chrome yellow WOOD S
Page 249 and 250: Fig. 7 - A soaked lamella clamped i
Page 253: (D) CONSERVATION
Page 256 and 257: EUROPEAN TECHNICAL COMMITTEE 346 -
Page 258 and 259:
EUROPEAN TECHNICAL COMMITTEE 346 -
Page 260 and 261:
Page 262 and 263:
Page 264 and 265:
THE WRECK OF VROUW MARIA - CURRENT
Page 266 and 267:
Page 268 and 269:
Page 270 and 271:
ROMANIAN ARCHITECTURAL WOODEN CULTU
Page 272 and 273:
Page 274 and 275:
Page 276 and 277:
RESSURREIÇÃO DE CRISTO - PANEL FR
Page 278 and 279:
ON 18 TH- AND 19 TH- CENTURY SACRIS
Page 280 and 281:
ON 18TH- AND 19TH- CENTURY SACRISTY
Page 282 and 283:
Page 284 and 285:
Page 286 and 287:
DEFIBRING OF HISTORICAL ROOF BEAM C
Page 288 and 289:
Page 290 and 291:
Page 292 and 293:
EXAMINATION AND CONSERVATION OF TWO
Page 294 and 295:
EXAMINATION AND CONSERVATION OF TWO
Page 296 and 297:
THE CONSEQUENCES OF WOODEN STRUCTUR
Page 298 and 299:
CONSEQUENCES OF WOODEN STRUCTURES C
Page 301 and 302:
WHAT ONE NEEDS TO KNOW FOR THE ASSE
Page 303 and 304:
Page 305 and 306:
Page 307 and 308:
Page 309 and 310:
Page 311 and 312:
load (KN) Samples 6 5 4 3 2 1 WOOD
Page 313 and 314:
STRUCTURAL BEHAVIOUR OF TRADITIONAL
Page 315 and 316:
Page 317 and 318:
Page 319 and 320:
Page 321 and 322:
Page 323 and 324:
Page 325:
Page 329 and 330:
INVESTIGATION ON THE UTILIZATION OF
Page 331 and 332:
Page 333 and 334:
Page 335 and 336:
Page 337 and 338:
3. Results and discussions WOOD SCI
Page 339 and 340:
Page 341:
Abadlia ......................... 3
Page 345 and 346:
ANNEX 1: FACTS ABOUT COST ACTION IE
Page 347 and 348:
Page 349 and 350:
Page 351 and 352:
Keynote presentations WOOD SCIENCE
Page 353 and 354:
Page 355 and 356:
Page 357 and 358:
Page 359 and 360:
Page 362:
Finito di stampare presso Grafiche
show all

Proceedings e report - Firenze University Press

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?