I. Report format
II. Appraisal Process
III. Test techniques
IV. Fire peformance of existing construction
Appendix A - List of testing
I. Report format (IStructE's manual)
1.0 Title:
1.1 Name or describe the building, or structure
1.2 Give its location
1.3 State for whom prepared (full name of the client)
1.4 State by whom (full name of engineer and/or firm)
2.0 Synopsis: Summarizing the problem and investigation carried out including significant features, and the principal conclusions and recommendations, including any important reservations and/or exclusions.
3.0 List of contents
4.0 Terms of reference (brief)
5.0 Documents examined: the document made available, e.g. clients or solicitor's letters, drawings and/or reports by others etc.
6.0 Description of the structure: It should be made brief and pictorial and include a potted history of its original construction, subsequent alterations, past and present use.
7.0 Inspections: To make it clear that an adequate number of inspections were made by adequately qualified people.
8.0 Additional (oral) information (if any)
9.0 Sampling and testing (if any)
10.0 Calculation checks (if any)
11.0 Discussion of evidence: Described the important of each of the findings. Any uncertainties remaining afte rthe investigation and any need for further checks should be stated here.
12.0 Conclusions: Reasoned judgments reached after careful assessments of the information obtained.
13.0 Recommendations: A brief description of the course of action that are available to the client as a logical follow-up the conclusions.
II. Appraisal Process
1. The path of appraisal
(a) The initial stage: Study and analyse on-hand information, check on possible mechanisms of failure, loadbearing capacity and margins of safety should be made. In particular, the inherent stability, robustness and adequacy of the structures should be examined.
(b) Second stage: (i) Calculations show that the structure has an adequate margin of safety according to relevant Code of Practice; (ii) grossly overloaded to the extent that the calculated overall factor or safety is unity or less; or (iii) indicate a factor of safety greater than unity but less than that recommended by the codes if any indication of overload.
2. Imposed load
The minimum design imposed load for buildings of domestic use varied from the equivalent load of 3.35 kPa in accordance with the 1915 version of the London County Council By-laws (LCC 1915) to 2.35 kPa in LCC 1938, 1.90 kPa in LCC 1952, 2.40 kPa in the Building (Construction) Regulations (BCR) 1975 and 2.50 kPa in BCR 1976 r.17 and 2.0kPa in BCR2011 and thereafter.
3. Load factors
BS8110
(i) Dead and imposed loads: 1.2(1.15G + 1.35Q) or 1.2 (0.85G + 0 Q) when dead load acting beneficially
(ii) Dead and wind loads: 1.2(0.9 x 0.85G x 1.0 x1.15W)
(iii) Dead, imposed and wind loads: 1.2 (0.9 x 1.15G x 0.75 x1.35Q+0.9 x1.105W)
Assessment in the Buildings Department
Case 1: 1.2D + 1.3L; and Case 2: 1.2D + 1.2L + 1.2W
where D = Actual permanent load; L = Actual usage load in compliance with current B(C)R or Code of Practice; W = Wind load
In case of imminent structural danger consider FOS, (i) less than 1.1 for cantilevered slabs; (ii) less than 1.0 for cantilevered beams; or (iii) less than 0.9 for other structural elements
4. Wind loads
Evolution of the Hong Kong wind code - HKIE
No statutory provision on the design of buildings for wind effects before 1956. In 1956, wind load requirements were prescribed in the Building (Construction) Regulations. In 1959, the detailed requirements were removed from the law and a Code of Practice on Wind Effects was published. Since then, a building has been deemed designed to the satisfaction of the Building Authority in respect of wind loads if its design complies with the Wind Code.
The basic wind pressures in the 1956 Regulations were specified under three degrees of exposure, based on 1 min wind velocities. The basic wind pressures in the 1956-1976 Wind Codes were
also based on 1 min wind velocities, but no longer took into account difference in exposure. The design wind pressures in the 1983 Wind Code were based on 3 sec gust velocities under two terrain categories. The design wind pressures in the 2004 Wind Code are based on 3 sec gust velocities for quasi-static wind loads and on hourly-mean velocities augmented by a gust factor for dynamically sensitive buildings. A single terrain was adopted in the 2004 Code.
Prior to the 1959 Wind Code, the basic wind pressure taken at roof level was assumed to act uniformly on the full height of the building for the calculation of total wind load. Since 1959, the design wind pressure corresponding to the height of the part of the building under consideration has been used. An implicit load coefficient of 1.2 was incorporated into the basic wind pressures in the Codes before 1983 to account for the net resultant on the windward and leeward sides. The wind pressures specified in the 1983 and 2004 Wind Codes were based on the dynamic air pressures only, without any implicit load coefficient.
5. Material utlimate stress
A. Concrete
(i) Ordinary and quality Concrete
Design Standard
|
B(C) Reg 1975 &1976,
LCC 1952 & 1964
|
LCC 1938
| ||
Concrete Designation Stress of concrete
|
Pcb lb/in2
(MPa)
|
fcu lb/in2
(MPa)
|
Pcb lb/in2
(MPa)
|
fcu lb/in2
(MPa)
|
| Grade I (1:1:2) | 970 (6.7) | 2,990 (20) | 975 (6.7) | 2,925 (20) |
| Grade II (1:1½::3) | 850 (5.9) | 2,550 (17.5) | 850 (5.9) | 2,550 (17.5) |
| Grade III (1:2:4) | 750 (5.2) | 2,250 (15) | 750 (5.2) | 2,250 (15) |
| Grade 1A (1:1:2A) | 1,500 (10.0) | 4,500 (31) | 1,250 (8.6) | 3,750 (26) |
| Grade IIA (1:1½::3A) | 1,250 (8.5) | 3,750 (26) | 1,100 (7.6) | 3,300 (22.8) |
| Grade IIIA (1:2:4A) | 1,000 (7.0) | 3,000 (20) | 950 (6.6) | 2,850 (19.7) |
Table 4 of General specification of the public works in Hong Kong
| Grade |
Minimum works cube strength 28days
(MPa)
|
Max aggregate size (mm)
|
Limits of aggregate/cement ratio by weight
|
Use of concrete unless otherwise stated
| |
max
|
min
| ||||
| A A1 |
20
|
20
40
|
7:1
8:1
|
5:1
6:1
|
Structure generally
Foundations
|
| B B1 |
25
|
20
40
|
5.5:1
6.5:1
|
4:1
4.5:1
|
High load columns
High load foundations
|
| C C1 |
30
|
20
40
|
5:1
|
3:1
|
High load columns
High load foundations
|
| H H1 |
15
|
20
40
|
10:1
|
8:1
|
Plinths under fittings
Blinding
|
| K K1 |
10
|
20
40
|
14:1
|
12:1
|
Mass filling
|
| L L1 |
7
|
20
40
|
24:1
|
18:1
|
Blinding under aircraft standing, etc.
|
(ii) Special and Designed Mix Concrete
fcu = Uw, works resistance to crushing of the concrete when tested within 28 days after mixing.
B. Reinforcement
Designation
|
Pst 1b/in2 (Mpa)
|
Fy 1b/in2 (MPa)
|
| Mild Steel | 16,000 (110) 18,000 (125) 20,000 (140) | 36,000 (250) |
| High Yield Steel | 27,000 (185) 30,000 (210) | 60,000 (410) 62,000 (425)* 67,000 (460)* |
*Characteristic strength for reinforcement in Code of Practice for Structural Use of Concrete 1987
460MPa - 6mm dia up to and including 16mm
425MPa - Over 16mm dia
Below items C - H are extracted from IStructE's manual
C. Cast iron, wrought iron and early mild steel
| Material | Ultimate strength | Yield strength | Elastic modulus (kN/mm²) |
| Cast iron Grey | Tension: 90-250 N/mm² Compression:775-1100N/mm² | 80-150 90-138 (BD21/93) | |
| Wrought iron | 21-24 tonf/in² (BS51:1939) | 220N/mm² (BD21/93) | 170-220 200 (BD21/93) |
| Mild Steel | 28-32 tonf/in² (BS15:1912) 230N/mm² (BD21/93) | 15-25 tonf/in² (BS15:1912) | 190-210 205 (BD 21/83) |
D. Structure stone
| Type | Density (kg/m³) | Compressive strength (N/mm²) | Water absorption (% of dry weight) |
| Granites | 1800 – 2900 | 140 – 250 | 0.19 – 0.30 |
| Sandstones | 1950 – 2750 | 25 – 70 | 2.4 – 10 |
| Limestones | 1800 - 2400 | 17 - 120 | 1 - 15 |
E. Compressive strength of bricks
(From IStructE's manual)
| Type of clay brick | Compressive strength (N/mm²) |
| Extruded | 20 - 200 |
| Machine moulded | 3.5 – 175 |
| Engineering | 50 – 70 |
| Flettons (normal) | 15 – 28 |
| Calcium silicate bricks | 7 – 35 (commonly 14-28) |
Mortar strength 0.5 – 1.0N/mm²
Strength of masonry: BS 5628 (strength: 40 - 200 N/mm²)
(From Building (Construction) Regulation 1964)
| Purpose |
Whether solid or hollow
|
Resistance to crushing in MPa of gross horizontal area
|
| External or internal (load bearing) |
Solid
|
10
|
| External or internal (load bearing) |
Hollow
|
5
|
| External (panel) (non-load bearing) |
Solid or hollow
|
3.5
|
| Internal (partition) (load bearing) |
Solid or hollow
|
1.5
|
F. Timber
(From Building (Construction) Regulation 1964)
Maximum permissible stresses in structural timber (other than post and struts) in MPa
| Kind of stresses | Class A | Class B |
| Flexural stress in extreme fibres (other than floor-borads) with adequate lateral restraint against winding or buckling) | 7.0 | 5.5 |
| Flexural stress in extreme fibres of floorboards | 5.5 | 5.5 |
| Shear stress in direction of grain | 0.7 | 0.7 |
| Compressive stress perpendicular to grain | 2.4 | 1.7 |
| Tension in direction of grain | 10.3 | 8.3 |
Maximum permissible stresses in structural timber (post and struts) in MPa
Ratio of effective length to
|
Class of timber
|
Ratio of effective length to
|
Class of timber
| ||||
Least radius of gyration
|
Least radius of dimension
|
A
|
B
|
Least radius of gyration
|
Least radius of dimension
|
A
|
B
|
0
|
0
|
7.0
|
5.5
|
80
|
23
|
4.8
|
3.9
|
10
|
3
|
6.7
|
5.4
|
90
|
26
|
4.2
|
3.4
|
20
|
6
|
6.6
|
5.3
|
100
|
29
|
3.6
|
2.9
|
30
|
9
|
6.5
|
5.2
|
120
|
35
|
2.8
|
2.2
|
40
|
11
|
6.3
|
5.0
|
140
|
40
|
2.1
|
1.7
|
50
|
14
|
6.0
|
4.8
|
160
|
46
|
1.6
|
1.3
|
60
|
17
|
5.7
|
4.5
|
180
|
52
|
1.4
|
1.1
|
70
|
20
|
5.3
|
4.3
|
200
|
58
|
1.1
|
0.9
|
· Machine stress-grading: Post- 1950, refer to BS4978 or standard of the country of origin)
· Visually stress-grading: for softwood CP112 (more easy use) or BS5268; for temperate hardwood BS5756 or currently guidance from TRADA.
Reference: i) Wood handbook : wood as an engineering material
G. Aluminium alloys (CP 118, BS8118)
| Specific gravity | E (kN/mm²) | 0.1% PS (N/mm²) | Tensile strength (N/mm²) | Permissible tension (N/mm²) |
| 2.7 – 2.8 | 65 - 70 | 230 – 280 | 280 – 310 | 100 - 150 |
H. Bronzes and brasses (for wrought bronze with 8% Sn)
| Temper | E (kN/mm²) | Tensile strength (N/mm²) | Yield stress (N/mm²) |
| Annealed | 110 | 400 | 170 |
| Hard | 110 | 650 | 600 |
| Spring | 110 | 750 | 725 |
See Appendix II of Practice Guidebook on Compliance with Building Safety Requirements for Adaptive Re-use of and Alteration and Addition Works to Heritage Buildings under the Buildings Ordinance (Interim Edition)
III. Test techniques (Details refer to Appendix A at bottom)
(Practical examples in Hong Kong see, Annual Concrete Seminar 2008, Works Branch Development Bureau)
1. Concrete structures:
· Strength and/or quality: T1 to T6
· Depth of carbonation: T7 & T8 (not in common use)
· Potential effects of alkali-silica reaction: T11
· Presence of chlorides and sulphates: T16
· Presence, position of, and cover to reinforcement: T21 & T22
· Extent of corrosion of reinforcement: T22 & T23
2. Iron, steel and other metal structure
· Identification of metal: T25 & T26
· Integrity: presence of cracks: T28 to T30
· Tensile strength: T31 & T32
· Weld defects: T36, T28, T29, T37 (not in common use) & T30
· Partial cracks in bolts: T20
3. Masonry
· Strength of clay units and of natural stone blocks: T40
· Strength of cement-based units: T1, T4, T5 & T40
· Mortar mix proportions: T10 (0.5 to 1kg)
· Presence and condition of wall ties, blockage of wall cavity: T24 & T22
4. Timber structures
· Species of timber: T46
· Insect attack: T47
· Fungal attack: T48
· Moisture content: T49, T18 & T49
· Strength grade: T46
IV. Fire performance of existing construction
1. Procedure for appraisal
Prescriptive approach – directly in accordance with approval plan and the relevant Codes of Practice. i.e. FRC, MOE & MOV;
A qualitative approach – with a clear logic with substantiates the performance;
A quantitative approach – involving a detailed and calculated assessment based on research or analytical modeling and possibly full scale fire tests.2. Fire safety requirement of structure (3 components): Loadbearing capacity or stability, Integrity (control of transmission of hot gases), and insulation (limitation of heat transfer). FRC required of element construction should be satisfied the exposure in Table 3 of MOE.
3. Fire engineering approach:
(i) Review current Codes of Practice
APP-87 or PNAP 204 11(h) - Structural Performance: predicts the thermal response and structural response of fire resisting elements at elevated temperatures and determines their equivalent fire resistance ratings; attention should also be given to the structural safety of adjacent buildings due to heat radiation near the site boundary.
App-85 or PNAP 202 para. 2(i), Fire Safety (Commercial Premises) Ordinance & Fire Safety (Buildings) Ordinance: A&A works in existing building
FRC Table 1 - Maximum compartment volumn. No compartment will exceed 28,000 m3.
MOE 15.9 - a building having a total capacity of >=10,000 persons necessitate consideration fire engineering approach.
MOE 8.4: Exit route lighting 30lux and backed up by emergency lighting not less that 2 lux
MOE 6 and FRC 14.1 : Special hazard, switch or meter room.
FRC 6.3 - Where a single storey building does not exceed 7 000m³, 7.5m in height and separation from adjoining building or site boundary not less than 6m, any steelwork construction may be unprotected.
Guidebook to Heritage Building 5.3 (d) to timber structure - (i) Installation of structural deck with adequate fire resistance; (ii) Sandwich approach (covered by fire-resisting materials); and (iii) Management approach.
(ii) Principle
The principle is to ensure that Available Safe Evacuation Time (ASET) (i.e. time to reach global and/or progressive collapse or time to untenability of the escape route) is always larger than the Required Safe Evacuation Time (RSET). ASET, which is most affected by smoke, depends on the tenability of the compartment and the escape route. Computational Fluid Dynamics (CFD) analysis can precisely predict the behaviour of fire and smoke in a fire and is a powerful tool to determine the ASET.
RSET = time to detect and alarm + time from alarm to response + travel time
(iii) Passive systems
These passive systems are built into the structures to provide the necessary stability and to separate the building into areas of manageable risk. They are designed to control the growth and spread of fire allowing the occupants to escape and the fire fighters to combat the fire.
(iv) Fire load
Standard testing data of various fire loads (in MW or MJ/m²) can be obtained from testing data of world recognised engineering handbook (e.g. SFPE Handbook of Fire Protection Engineering) or research laboratories (e.g. Building and Fire Research laboratory of National Institute Standards and Technology).
4. Material
Concrete: -
(i) Strength reduction factors for normal weight concrete at elevated temperatures may be referred to Table 12.2c of CoP in Structural Use of Steel 2005.
Below items (ii) to (vi) are recommended by IStructE.
(ii) The compressive strength of concrete is little affected up to 300°C. Concrete has a low thermal diffusivity (approximately 1mm²/s), therefore the 300°C and 500°C contour are at relatively shallow depths at the outer 30 to 50mm.
The residual strength of concrete after cooling and corresponding fire-damage factor (Appendix 5 of IStructE’s manual):
| Temperature range (°C) |
Resultant strength
|
Damage factor
|
| 100 – 300 |
85
|
0.85
|
| 300 – 500 |
40
|
0.4
|
| Over 500 |
0
|
0.0
|
(iii) Creep becomes significant due to large reduction of the elastic modulus and is of order 10-4 to 10-3 over range of 250°C to 700°C but can have a beneficial effect in relaxing inbuilt temperature-induced stresses.
(iv) Cracks can be visible or hidden or along reinforcement bars or heavily reinforcement area. Spalling is a common effect on the corners of columns and beams.
(v) Reduction of bond strength is dependent on the duration, type of rebar and condition. Conservatively, 30% reduction in bond for the 100°C to 300°C range could be assumed, i.e. fire-damage factor is taken 0.7.
(vi) For prestressed concrete, a 50% reduction in the tensile strength when the steel temperature reaches between 370°C and 420°C. At 700°C, the strength of prestressing wires is reduced to less than 7%.
Structural steel
(i) Fire resistance design (Ch. 12 of CoP in Structural Use of Steel)
a). Standard fire T = 345 log10 (8t +1) + 20 (12.1)
Where T = design fire temperature (°C); t = elapsed time (minutes)
BSEN1991-1-2 provides three nominal fire curves
b) Natural fire
A natural fire refers to a fire exposure that builds up and decays in accordance with the mass and energy balance within a compartment.
c) Strength reduction factors for hot-rolled and cold-formed steel at elevated temperatures may be referred to Table 12.2a & Table 12.2b of CoP in Structural Use of Steel 2005.
d) Strength reduction factors for cold worked rebar and bolt & weld at elevated temperatures may be referred to Table 12.2d & Table 12.3 of CoP in Structural Use of Steel 2005.
e) Apart from HK Codes, the structural fire assessment has been made mainly on individual elements under standard fire condition may refer to BS 5950: Part 8: 1990.
Below items (ii) to (vi) are recommended by IStructE
(ii) The yield strength is reduced to 50% at 550°C to 10% at 1000°C. The coefficient of expansion is of the order of 10-5/°C. (recommended by IStructE)
(iii) The yield strength after cooling is recovered for both hot-rolled and cold-formed steel from temperature of 500°C to 600°C and reduced from 800°C by 5% for hot-rolled and by 30% for cold-formed steel. (recommended by IStructE)
(iv) The creep rate is sensitive for mild steel above 450°C. (recommended by IStructE)
(v) Normal maximum stress of Grade 4.6 and Grade 8.8 bolts should give an adequate performance in fire of 360°C to 425°C, and be reduced when heated above 600°C for Grade 4.6 and above 400°C for Grade 8.8.
(vi) For cast iron, the residual strength has no reduced up to 600°C and should be reduced by 50% at 750°C. Grey iron may crack if above 350°C.
(vii) Fire Protection Materials Characteristics of fire protection system
| Type | Sprayed cementitious or gypsum based coatings to BS476 Part 4 | Boards and blankets | Intumescent coatings to BS8202 Part 2 |
| Cost | Low to medium | Low to high | Medium to high |
| Application | Messy, with protection required to adjacent surface | Relatively clean, labour intensive | If applied on site protection required to adjacent surfaces, otherwise use off-site |
| Internal / external use | Internal and external materials available. Not all suitable for external use | Internal use. Additional protection required for external use | Internal with some external system |
| Finish | Textured finish | variable | Smooth or slightly textured surface |
| Thickness | 10 to 75mm | Board 6 to 100mm; batts/blankets 12 to 76mm | Thin film: 0.3 to 6.5mm; thick film: 2.0 to 32mm |
| Max FRP | 4 hours | 4 hours | Thin film: 2 hours; thick film: 4 hours |
Reference:
- Association for Specialist Fire Protection. Fire protection for structural steel in buildings
- The Building Regulation 2000. Approved Document B: fire safety
Timber
(i) Timber is combustible and will easily burn out under fire. Timber shows brown colour at about 120°C–150°C, black colour around 200°C–250°C and evolves combustible vapours at about 300°C. At about 400°C to 450°C (or 300°C if a flame is present), the surface of timber will ignite and char at a steady rate. Only charred parts of a section lose all their strength whereas the remaining parts may assume to have no significant loss in strength.
(ii) Some typical charring rates are recommended by IStructE
| Species |
30min (mm)
|
60min (mm)
| |
| (a) | All structural species except those in item (b) and (c) |
20
|
40
|
| (b) | Western red cedar |
25
|
50
|
| (c) | Oak, utile, keruing, gurjun, teak, greenheart, jarrah |
15
|
30
|
(iii) Protection
Fire retarded can be used to improve the surface spread of flame charateristics, with impregnation methods being preferable unless maintenance of surface treatments can be provided. The retardant does not improve the resistance, because even though the timber is relatively non-combustible the timber will still char in the event of a fully developement fire.
(iv) Established practice (Eurocode 5 and BS5268)
Temperature at an actual char-line in softwood is typically about 300°C.
Depth of char (mm): d char = b0 x t
where bo = charring rate; t = time (min)
Effective cross section: deff = d char + k0 d0
where d0 obtained from test calibration; coefficient k0 table in EC5.
Aluminum
Maximum temperature limit of 200°C – 250°C
Masonry
i. FRC
ii. Table 15 of BS5628 Part3:2001
iii. Table 1-3 of BR128, BRE1988 Guidelines for the construction of fire resisting structural elements
iv. Table 2 of Eurocode 6 Desgin of mansonry structures, Part 1-2 General Rules - Structural Fire Design
Fire Protection Materials
Characteristics of fire protection system
| Type | Sprayed cementitious or gypsum based coatings to BS476 Part 4 | Boards and blankets | Intumescent coatings to BS8202 Part 2 |
| Cost | Low to medium | Low to high | Medium to high |
| Application | Messy, with protection required to adjacent surface | Relatively clean, labour intensive | If applied on site protection required to adjacent surfaces, otherwise use off-site |
| Internal / external use | Internal and external materials available. Not all suitable for external use | Internal use. Additional protection required for external use | Internal with some external system |
| Finish | Textured finish | variable | Smooth or slightly textured surface |
| Thickness | 10 to 75mm | Board 6 to 100mm; batts/blankets 12 to 76mm | Thin film: 0.3 to 6.5mm; thick film: 2.0 to 32mm |
| Max FRP | 4 hours | 4 hours | Thin film: 2 hours; thick film: 4 hours |
Relevant websites:
· ASTM International
· BSI
· BRE
· CIRIA
· CIMTEC Conference
· Concrete Society
· RILEM
· HOKLAS
· Quick Solutions - Prescriptive Approach, the University of Manchester
Appendix A - List of testing (proposed by IStructE manual)
· T1 Rebound hammer (BS EN 12504-2: 2001 entitled ‘Testing concrete in structures – Part 2; or BS1881:Testing concrete, Part 202:1986)
· T2 Ultrasonic pulse velocity - concrete (BS1881:Testing concrete, Part 203:1986)
· T3 Core testing (Building (Construction) Regulation 63 and section 15 of CS 1:1990; or BS6089:1981)
· T4 Internal frature test for concrete (BS1881:Testing concrete, Part 207:1992)
· T5 Windsor proble (Technical Note 143, CIRIA)
· T6 Break-off test (Norwegian method) (BS1881:Testing concrete, Part 207:1992)
· T7 Phenolphthalein test (not applicable to HAC concretes) (Technical Note 143, CIRIA)
· T8 Microscopy studies (Technical report TR32, Concrete Society)
· T9 Free lime content - depth of carbonation (Technical report TR32, Concrete Society)
· T10(a) Cement content and cement/aggregate ratio (Technical report TR32, Concrete Society)
· T10(b) Type of cement (Technical report TR32, Concrete Society)
· T10(c) Type of aggregate (Technical report TR32, Concrete Society)
· T11 Latent expansion test (The diagnosis of alkali-silica reaction, BCA, 1988)
· T12 Water/cement ratio (Technical report TR32, Concrete Society)
· T13 Initial surface absorption test (ISAT) (Technical report TR31, Concrete Society)
· T14 Water and gas permeability tests (Technical report TR31, Concrete Society)
· T15 Absorption test (BS1881:Testing concrete, Part 122:1983)
· T16 Tests for chloride content (IP21/86, BRE, Garston 1986)
· T17 Admistures and contaminants (Technical report TR32, Concrete Society)
· T18 Direct moisture measurement of concrete, masonry products and timber (BS5268: Structural use of timber, Part 2:1991)
· T19 Abrasion resistance testing (Technical note 143, CIRIA)
· T20 Air entrainment (Technical report TR32, Concrete Society)
· T21 Covermeter (BS1881:Testing concrete, Part 204:1988)
· T22 Physical exposure ('Inspection of cables in post-tensioning bridges - what techniques are available', Structural faults and repair 96, Vol 1, Engineering Technics Press, 1993)
· T23 Electrical potential (ASTM:C876)
· T24 Enoprobe and boroscope (IP13/90, BRE, Garton 1990)
· T25 Visual identification of wrought iron and cast iron ('Practical building conservation' Vol 4, Metals, English Hertiage technical handbook)
· T26 Chemical analysis of metals ('Basic metallurgy for NDT testing', Institution of Non-destructive Testing, 1989)
· T27 Metallography (BS6533:1984)
· T28 Dye penetrants (BS4080: Specification for severity levels for discontinuities in steel castings, Part 2:1989)
· T29 Ultrasonics -steel and other metals (BS7448: Fracture mechanics toughness tests, Part 1:1991; BS4124:1991; and BS6208:1990)
· T30 Radiographic techniques for metals (BS2600, Part 1:1983)
· T31 Hardness tests (BS240:19891; BS427:1990; BS860:1989; BS891:1989; and BS4175:1989)
· T32 Tensile tests ( CS2:1995; or BS EN 10002-1:1990; and BS EN 10002-5:1992)
· T33 Wedge penetration test for cast iron (British Cast Iron Research Associate publications)
· T34 Split-cylinder test for test cast iron
· T35 Impact test (BS7448: Fracture mechanics toughness tests, Part 1:1991; and BS131: Methods for notches bar tests, Part 1)
· T36 Visual examination for weld defects (BS5289:1976)
· T37 Magnetic-particle crack detection (BS6072:1986; BS4080:Part 1:1989; and PD6513:1985)
· T38 Chemical tests of bronzes ('Stress corrosion of metals', Corrosion monograph, Wiley, 1966)
· T39 Condition of steel cables
· T40 Crushing of masonry cores, units or sawn-out samples (RILEM Recommendations for the testing and use of construction materials, Part 7)
· T41 Helix pull-out test (The non-destructive evaluation of masonry materials in structures', Processings 8th CIMTEC world conference, 1994)
· T42 Split-cylinder tests
· T43 Flatjack test (BRE Digest 409, 1995)
· T44 Shove test (insitu shear) (ASTM Standard C1197)
· T45 Wall-tie detection (IP12/90 and IP13/90, BRE, Garston 1990)
· T46 Visual examination of timber (BR232, BRE, Garston 1992)
· T47 Identification of insect attack (BR 232, BRE, Garston 1992; Timber pests and their control, Manograph; and Digest 307, BRE, Gartson)
· T48 Identification of dry rot/wet rot (BR98, BRE, Garston 1987; and Digest 307, BRE, Gartson)
· T49 Moisture content of timber (Timber designers' manuual, Granada Technical Books, 1984)
· T50 Mechanical properties of timber (BS 5268:Part 2:1991; and BS4978:1988)
· T51 Identification of glues (IP8, BRE, Garston 1984; and IS9, BRE Garston 1975)
· T52 Identification of preservative treatments (BS 5666, Part 2:1980)
· T53 Identification of type of plastics (BS2782)
· T54 Ultrasonics -plastics
沒有留言:
張貼留言