Durability and maintenance - Appunti - Voto 30

SERVICE LIFE PERFORMANCE LIMIT

Synopsis concerning the significant entities for the decay phenomena analysis of the reinforced concrete

Agents – Actions EFECTS for reinforce concrete

Prof. Bruno DANIOTTI – THE DURABILITY EXPERIMENTAL EVALUATION OF BUILDING COMPONENTS 04 - 5

Agents Actions Effect

• Corrosion
• Rain Washing away with CO Erosion
• Wind penetration
• CO2 Rain Water penetration and O Slits, iron cover disjunction
• Steam Reinforcement corrosion
• O2 Carbonization
• Steam Steam permeability CO2 Corrosion
• CO absorption

Durability Analysis - Definitions

• Wind Particles push and friction Abrasion
• Particles
• Ice Intense cold-thaw Cracking
• (ref. CIB W86 Building Pathology) Superficial breaking up
• Temperature cycles
• Animals Biological attack Biological increase
• • agent: entity which causes a certain effect throughout its action (ex: wind, air humidity, solar or thermal radiation, etc.).

Prof. Bruno DANIOTTI – THE DURABILITY EXPERIMENTAL EVALUATION OF

BUILDING COMPONENTS 04 - 14 • action: physical-chemical or mechanical intermediary PERFORMANCE ANALYSIS/FUNCTIONAL ANALYSIS TECHNOLOGICAL REQUIREMENTS BASIC FUNCTIONS CONTROL OF INTERSTITIAL CONDENSATION CONTROL OF SURFACE CONDENSATION CONTROL OF SUMMER THERMAL DYNAMIC BEHAVIOUR Durabilità dei materiali e manutenzione CONTROL OF WINTER THERMAL DYNAMIC BEHAVIOUR AIRBORNE SOUND INSULATION THERMAL INSULATION MECHANICAL RESISTANCE TO HANGING LOADS WATER TIGHTNESS FUNCTIONAL ANALYSES FUNCTIONAL ANALYSIS: to identify the functions of each material and the properties to be measured TECHNICAL SOLUTION It represents the structure ofIl componente con i prodotti costituenti il componente e le loro proprietà REQUISITO TECNOLOGICO: ISOLAMENTO TERMICO modello dell'oggetto - 1n Il modello dell'oggetto rappresenta gli oggetti (elementi funzionali o strati) con specifici livelli di caratteristiche funzionali. REQUISITO TECNOLOGICO: TRASMITTANZA TERMICA U (W/m K) 2 i ej Resistenza termica dello strato (m K/W): 2 λj j CARATTERISTICHE FUNZIONALI: Conducibilità termica (W/m K) spessore elementi funzionali: Spessore s (m) (cm) modello funzionale 1 copertura in plastica acrilica 0,2 2 intonaco rustico 1,3 3 mattoni semipieni 12 4 colla sintetica-cemento 5 pannelli in fibra di vetro 4 6 mattoni vuoti 8 7 intonaco interno 1,5 8 pittura acrilica FUNZIONI ANALITICHE CARATTERISTICHE FUNZIONALI Prof. Bruno DANIOTTI - VALUTAZIONE SPERIMENTALE DELLA DURABILITÀ DEI COMPONENTI EDILIZI 04 -

Parameters	fa	fb	fc	fd	fe	ff	fg
to resist to radiative heat flows	thermal radiation absorption coefficient
to resist to convective heat flows		thickness	air speed (air cavities)
Relative Vapourthickne density				specific heat, thermal conductivity thickness
Thermal Specific Relative Relative Winter SurfaceVapour resistancess Conductivity
heat Thermal summer TTC TTC. Mass
to resist to conductive heat flows			thermal conductivity	resistance
thickness	3	2	2n	cm	kg/m	W/mK	kJ/K
adim.	m	sPa/kg	%	%	h	kg/m
to foster convective heat flows					thickness	2	1,5
1800,0	0,9	0,91	35	28,00	1,01	28,85	0,41
27,0	air speed (air cavities)	3	12,0	1070,0	0,44	0,84	7
44,80	16,6	15,89	29,42	128,4
to foster water re-evaporation					thickness	4,0	30
0,036	0,97	1	2,13	67,5	0,73	1,29	1,2
open surface porosity
to resist to water vapour permeation						relative resistance to water vapour diffusion	5
8,0	730,0	0,35	0,84	6	25,60	13,9	53,43
11,21

58,4thicknessFUNCTIONAL ANALYSES6 1,5 1800,0 0,9 0,91 35 28,00 1,01 28,85 0,41 27,0fh to provide water vapour permeation relative resistance to water vapour diffusionSelf Supporting External Wall (PV2) thicknessProf. Bruno DANIOTTI – THE DURABILITY EXPERIMENTAL EVALUATION OF BUILDING COMPONENTS 04 - 18ANALYTICAL FUNCTIONSthicknessfi to provide Constant resistance to water vapour permeation relative resistance to water vapour diffusionfunctional elements: (cm) fa to resist to radiative heat flowsfb to resist to convective heat flows1 acrylic plastic covering 0,2fl to provide constant resistance to heat transmission thermal conductivity1,32 rustic plaster fc to resist to conductive heat flows3 semi-hollow bricks 12fm to hinder by mass the transmission of sound waves density fd to provide heat storageS synthetic-cement glue4 glass fibre panels 4 Thickness fe to foster convective heat flows5 hollow bricks 8fn to interrupt the transmission of sound waves in solids air speed (air

• cavities)
• ff to foster water re-evaporation
• internal plaster 1,5 thickness
• acrylic painting fg to resist to water vapour permeation
• fo to provide visco-elastic dampening in solid mean visco-elasticity
• fh to provide water vapour permeation
• fp to provide air-tightness air tightness
• fi to provide Constant resistance to water vapour
• Object Model
• fq to provide acoustic absorption acoustic absorption coefficient
• permeation
• Dr.Bruno Daniotti- Politecnico di Milano FUNCTIONAL ELEMENTS
• fr to provide compressive strength compressive strength
• fl to provide constant resistance to heat transmission
• IE 1 2 3 S 4 5 6 7
• fs to provide bending strength bending strength
• F1 fh.1 fh.1 fh.1 fc.1 fm to hinder by mass the transmission of sound
• ft to provide resistance to water flow water tightness
• F2 fc’.2 fc.2 fc’.2 ff.2 wavesthickness
• F3 fc’.3 fc.3 fd.3 fn to interrupt the transmission of sound waves in
• F4 fc’.4 fc.4 fd’.4
• fu to provide opposition to capillary water permeation hydrophily

21Quando conosciamo quali sono: - Caratteristiche dei materiali; - Prestazioni del componente; - Meccanismi di degrado; Andiamo all'obiettivo di pre-test: simulare gli agenti in laboratorio e confrontarli con le informazioni attuali provenienti dall'ispezione dell'edificio. Successivamente abbiamo la valutazione della previsione della durata di servizio Qc, Qo, Qm .... Qu. ANALISI DELLE PRESTAZIONI E FUNZIONALI MECCANISMI DI DEGRADO DEFINIZIONE DELLA DEFINIZIONE DELLE PRESTAZIONI E CICLI DI INVECCHIAMENTO LIMITI FUNZIONALI SPERIMENTAZIONE 1. MISURARE LA PRESTAZIONE INIZIALE P (t) 0 0 MISURARE IL DECADIMENTO DELLA PRESTAZIONE NEL TEMPO P(t) 3. VALUTARE LA FINE DELLA VITA UTILE VALUTAZIONE DEI COMPONENTI EDIFICI 04 - 23 Misuriamo attraverso Durabilità dei materiali e manutenzione invecchiamento accelerato in laboratorio PROGRAMMA SPERIMENTALE PACCHETTO ESTERNO [PS] COMPONENTE INTERO [WS] Q Q Q Q Qt0 ot m osot INVECCHIAMENTO ESTERNO INVECCHIAMENTO ACCELERATO INVECCHIAMENTO ACCELERATO ESPOSIZIONE ALL'APERTO ESPOSIZIONE ALL'APERTO LABORATORIO INVECCHIAMENTO NATURALE REALE TECNOLOGICO EDIFICI LABORATORIO RI - SCALARE IL TEMPO RI-SCALARE

EXPERIMENTAL EVALUATION SAMPLE PAINTS

SAH = Acrylic paint with High resin ratio (CVP40)

AL = Acrylic paint with Low resin ratio (CVP60)

VH = Vinylversatic paint with High resin ratio (CVP40)

VL= Vinylversatic paint with Low resin ratio (CVP60)

Prof. Bruno DANIOTTI – THE DURABILITY EXPERIMENTAL EVALUATION OF BUILDING COMPONENTS 04 - 25

The durability experimental evaluation of building components: methods for measuring performance characteristic decay

Testing activity is related with the comparison between laboratory testing and outdoor exposure.

• Non disruptive tests:
  • Painting’s surface photographs
  • Mass increase the change in mass depends from water entering, it’s better to have less à water entering and this is for acrylic CVP 40, which has the highest level of resin.
• Disruptive tests:
  • Plasters microstructure composition
  • Plaster porosity
  • Plaster water absorption
  • Plaster water vapour permeability
  • Plaster compression strength
  • Bonding strength

between plaster and brickIn the microscope photograph we can observe:

• Gel Pores, nm∅ ∼
• Capillary Pores, μm∅ ∼
• Air Pores, mm∅ ∼
• Cracks
• Aggregates
• Interfaces between aggregate and cement

Porosity test

In order to evaluate the porosity we use a device

The sample is introduce in and we can measure different conditions:

The apparatus dives a pressure to the water in order to make it enter in the sample so we can measure the mass of the sample before and after

Water absorption test

The second test is water absorption, the sample is put in low level of water in order to force water enter in the sample, on one side the sample is covered with silicone in order to avoid water entering on this side. It is measure the difference of weight before and during water absorption. After 10 min, 1 hour and 24 hours.

Water vapor permeability test

It is used a cup inside which is put very dry sold in order to keep the inside dry (10%) over the cup is positioned the sample, which

The cover is coated with silicon on one side. Then it is measured.