Lecture 1_Structural Assessment_Dr. Lim(1).

REFRESHER COURSE ON STRUCTURAL FORENSIC:
“STRUCTURAL ASSESSMENT”
IR. DR. LIM CHAR CHING
Bahagian Forensik Struktur
Cawangan Kejuruteraan Awam dan Struktur
Ibu Pejabat JKR Malaysia
Kuala Lumpur
CKAS
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Forensic Investigation: Present Procedure
JKR DAERAH/NEGERI
CAW SENGGARA
CKASJ
BSFB (HOPT).
Koordinasi dgn
semua HODT
Terima Aduan
Kerosakan
Struktur
Terima Aduan
Kerosakan Bang.
dari Pelanggan
Laporan
Awalan
Pemeriksaan
Awalan
Pemeriksaan
Awalan (Borang
Siasatan Awalan)
Laksanakan
Ujian Bahan
Mula
Laksanakan
Pembaikan
Struktur
Keputusan
Ujian Bahan
Perolehan
Sedia MTP,
BQ, SOW
Pemeriksaan
Terperinci
Sediakan Lukisan
Pembaikan &
Spesifikasi
Tamat
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1
Komponen Bangunan
1. Sistem bumbung
2. Struktur konkrit keluli bertetulang
3. Asas
4. Kerja sivil (sistem paip, pembentungan,
saliran, dsbnya)
5. M & E (pendawaian, air
air--con, sistem
pencegahan kebakaran, etc)
6. Kerja
Kerja--kerja senibina (finishings, fittings)
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Why Structural Assessment ?
Design
Construction
Structure
Material
Deterioration
Structural
Failure
Fire
Change in
Use
Explosion/
Earthquake
Assessment
Determine Structural Safety
(Strength & Functionality)
Remedial
Measures
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End
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Carta Aliran Penilaian Struktur
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The Structural Assessment Process (1)
Desk study
Preliminary inspection
Plan main investigation
INITIAL
PHASE
Main investigation
Sampling
Testing
Lab test
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Mapping
Structural assessment/design issue
Appraisal & Evaluation
Continue
DETAILED
PHASE
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The Structural Assessment Process (2)
Continue
Interpretation of Results
Structural Assessment
(Safety, Residual Strength)
Repair Method
(Rehabilitate, Strengthen)
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Sekolah Menengah Sains Miri:
Blok Asrama Putera
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Contoh Pelan Ujian Bahan (1)
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Contoh Pelan Ujian Bahan (2)
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Contoh Pelan Ujian Bahan (3)
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Pemeriksaan Awalan
(Condition Survey)
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Types of Cracks
“Cracks are symptomatic of various types of
deterioration, overloading or deficiencies in design
or detailing”.
1. “Structural Cracks” (Load
(Load--induced Cracks)
- due to structural instability
- bending, shear, compression, torsion
2. “Non
“Non--Structural Cracks” (Environment(Environmentinduced Cracks)
- due to material properties
- shrinkage and creep
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Classification of Structural Cracks (1)
Bending Cracks in Beam
Load
Bending cracks
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Classification of Structural Cracks (2)
Shear Cracks in Beam
Load
Shear cracks
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Classification of Structural Cracks (3)
Compression Failure in Column
Load
Compression
Failure Cracks
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Classification of Structural Cracks (4)
Torsional Cracks in Beam
TORSION
Torsional cracks
Torsion
TORSION
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Classification of Cracks (1)
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Classification of Cracks (2)
Type of
cracking
Plastic
Settlement
Legend
A
Primary
cause
Secondary
causes/factors
Remedy
Excess
bleeding
Rapid Early
Drying
Conditions
Reduce Bleeding
(Air Entrainment)
Or ReRe-Vibrate
Rapid early
drying
Low Rate Of
Bleeding
Improve Early
Curing
B
C
Plastic
Shrinkage
D
E
F
Ditto Plus Steel
Near Surface
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Copyright © 2011 Dr. Lim Char Ching
Classification of Cracks (3)
Type of
cracking
Legend
Early Thermal
Contraction
G
Excess Heat
Generation
H
Excess
Temperature
Gradients
I
Inefficient
Joints
Excess
Reduce
Shrinkage
Water
Inefficient Curing Content
Improve
Curing
J
Impermeable
Formwork
Rich Mixes
Poor Curing
K
Over
Over--Trowelling
Long-Term
LongDrying
Primary cause
Shrinkage
Crazing
Secondary
causes/factors
Rapid Cooling
Copyright © 2011 Dr. Lim Char Ching
Remedy
Reduce Heat
And/Or
Insulate
Improve
Curing And
Finishing
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Classification of Cracks (4)
Type of
cracking
Corrosion Of
Reinforcement
Alkali-Silica
AlkaliReaction
Legend
Primary cause
Secondary
causes/factors
L
Lack Of
Cover
Poor Quality
Concrete
M
Excess Calcium
Chloride
N
Reactive Aggregate Plus HighHigh-Alkali
Cement
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Remedy
Eliminate
Causes
Listed
Eliminate
Causes
Listed
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Types of Cracks: Shear
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Types of Cracks: Shear
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Types of Cracks: Shear in Corbel
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Types of Cracks: Shear in Corbel
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Shear Cracks in Cantilever Beam
Load
Load
Type 1:
Diagonal Tension Cracks
Type 2:
Diagonal Compression
Cracks
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Types of Cracks
Bending Crack in Beam (over support)
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Types of Cracks:
Differential
Settlement
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Types of Cracks:
Drying Shrinkage
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Types of Cracks:
Drying Shrinkage
Shrinkage cracks on
floor slab
Shrinkage cracks on beams.
Similar cracks can also happen
on columns
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Types of Cracks:
Chloride--Induced Steel Corrosion
Chloride
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Types of Cracks:
Chloride--Induced Steel Corrosion
Chloride
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Types of Cracks:
Chloride--Induced Steel Corrosion
Chloride
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Crack Width Monitoring
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Demountable Mechanical (Demec
(Demec)) Gauge
crack
disc
R3
R1
R2
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Results of Crack Width Monitoring
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Avongard Crack Gauge
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Installation of Avongard Crack Gauge
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Examples of NonNon-Structural Cracks
(Plaster Cracks)
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Types of Cracks:
Drying Shrinkage
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Drying Shrinkage Cracks:
Beam
Beam
Wall
Plaster
Brickwall
Plaster cracks at interface
between beam and brickwall
brickwall**
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Column
RWDP pecah akibat
mendapan apron
Brick box-up
Keretakan antara “Box“Box-up”
dengan Tiang Konkrit
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RWDP in column
column
RWDP
sump
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Keretakan
lazim berlaku
di sini !!
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Struktur tangga
Struktur bangunan
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Struktur tangga
Struktur bangunan
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Kerosakan Waterproofing Di Bilik Air
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Kerosakan Waterproofing Di Bumbung Rata
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Keretakan Screed
Pada Papak Lantai
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Tiada Keretakan Pada Papak Lantai:
Bukan Isu Struktur
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Keretakan Lepaan
Dinding Disebabkan
“Electrical Conduit”
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