FORENSIC ENGINEERING PRINSIP DAN IMPLEMENTASINYA DI INDONESIA Prof.Ir.Bambang Suhendro,M.Sc.,Ph.D. Department of Civil & Environmental Engineering Faculty of Engineering Universitas Gadjah Mada 2015
MATERI o Pendahuluan o Penyebab Degradasi dan Keruntuhan Infrastruktur o Peralatan Investigasi
o Prinsip Dasar Forensic Engineering o Kurikulum Pendidikan Forensic Engineer o Berbagai Contoh Kasus Forensic Engineering
o Berbagai Contoh Kasus di Indonesia o Penutup
PENDAHULUAN Permasalahan yang dihadapi dalam bidang Teknik Sipil :
perancangan (design) suatu struktur baru pelaksanaan pembangunannya (construction), pengelolaan, pengoperasian, dan perawatan existing infrastructures, evaluasi teknis untuk menilai kelayakan-pakai suatu infrastruktur selama masa layannya (useful life), dan metode repair/strengthening apa bila diperlukan
Quality of existing structures
Infrastructure Management System Strength, Stiffness, Serviceability, Stability, Durability
Minimum requirement
monitoring, evaluation, repair Infrastructure Management System time
Desgn Construction years)
Operation (life time > 50
Berbagai peristiwa yang "tidak diinginkan" seperti: kecelakaan, kerusakan, degradasi kekuatan, dan keruntuhan dapat terjadi pada masa : pelaksanaan, atau pengoperasian suatu infrastruktur, yang dapat menimbulkan: kerugian-kerugian materi, korban jiwa, terganggunya stabilitas ekonomi, sosial, dan politik.
Pada kondisi ini berbagai fihak seperti: a) lembaga pengadilan, b) kepolisian,
c) pemerintah-daerah setempat yang terkait dengan perijinan bangunan, d) asuransi, e) pemilik bangunan, dan tidak ketinggalan f) konsultan perencana/pengawas serta g) kontraktor pada saat pembangunannya,
akan dapat dilibatkan untuk menetapkan
siapa yang "bersalah", seberapa besar "ganti-rugi" yang harus dibayarkan kepada fihak yang dirugikan.
Situasi yang demikian sangat memerlukan peran Forensic Engineering untuk membantu mengungkapkan permasalahan yang sebenarnya secara proporsional, yang secara umum akan meliputi aspek-aspek: Investigasi
Evaluasi Kesaksian ahli di depan pengadilan
ASCE (American Society of Civil Engineers) resmi membentuk Committee on Forensic Engineering pada tahun 1982, Saat ini telah berganti nama menjadi Technical Council of Forensic Engineering (TCFE). Konferensi Nasional pertama digelar oleh ASCE di Seattle, Washington, pada tanggal 7 April 1986,
dengan tema: “ Forensic Engineering: Learning from Failures "
Jurnal ilmiah Forensic Engineering JPCF telah
diterbitkan rutin 3 bulanan sejak Februari 1987 dan mendapatkan respon yang sangat baik dari berbagai kalangan profesi: Engineering, lawyer, architects, government, insurance executives, dan owners. Konferensi berikutnya digelar oleh TCFE-ASCE pada tanggal 5~8 Oktober 1997 di Minneapolis,
Minnesota,
Sejak itu beberapa Universitas di USA telah mulai mengajarkan mata kuliah
Forensic Engineering dalam kurikulum akademisnya. Bagaimana dengan di Indonesia ?
Historic Example 1847
•
•
One of the earliest in the modern period being the fall of the Dee bridge at Chester, England. It was built using cast iron girders, each of which was made of three very large castings dovetailed together. Each girder was strengthened by wrought iron bars along the length. It was finished in September 1846, and opened for local traffic after approval by the first Railway Inspector, General Charles Pasley. However, on 24 May 1847, a local train to Ruabon fell through the bridge. The accident resulted in five deaths (three passengers, the train guard, and the locomotive fireman) and nine serious injuries. The bridge had been designed by Robert Stephenson, and he was accused of negligence by a local inquest. Although strong in compression, cast iron was known to be brittle in tension or bending, yet, on the day of the accident, the bridge deck was covered with track ballast to prevent the oak beams supporting the track from catching fire. Stephenson took this precaution because of a recent fire on the Great Western Railway at Uxbridge, London, where Isambard Kingdom Brunel's bridge caught fire and collapsed. This act imposed a heavy extra load on the girders supporting the bridge, and probably exacerbated the accident.
Historic Example 1847
•
One of theOne of the first major inquiries conducted by the newly formed Railway Inspectorate was conducted by Captain Simmons of the Royal Engineers, and his report suggested that repeated flexing of the girder weakened it substantially. He examined the broken parts of the main girder, and confirmed that the girder had broken in two places, the first break occurring at the center. He tested the remaining girders by driving a locomotive across them, and found that they deflected by several inches under the moving load. He concluded that the design was flawed, and that the wrought iron trusses fixed to the girders did not reinforce the girders at all, which was a conclusion also reached by the jury at the inquest. Stephenson's design had depended on the wrought iron trusses to strengthen the final structures, but they were anchored on the cast iron girders themselves, and so deformed with any load on the bridge. Others (especially Stephenson) argued that the train had derailed and hit the girder, the impact force causing it to fracture. However, eye witnesses maintained that the girder broke first and the fact that the locomotive remained on the track showed otherwise.
Forensic Engineering
Forensic Engineer • The forensic engineer applies the art and science of engineering to the purpose of the law. Most requests for services involve civil suits. However, the forensic engineer may also assist in the prosecution or defense of criminal or regulatory matters.
• Typical subjects include: failure analysis, accident reconstruction, causes and origins of fires or explosions, design review, quality evaluation of construction or manufacturing, maintenance procedures, and environment definition.
Jurisprudence • Attorneys for the prosecution and the defense, as well as the judge, are lawyers. They are the main players in the drama of the courtroom. The lawyer who uses expert testimony in criminal and civil cases must be knowledgeable of the law that governs the admissibility of forensic evidence, and qualified to apply this law to present and challenge forensic evidence in depositions and court proceedings. The judge must understand all the issues and make sure of the legality of the entire process.
PENGERTIAN FORENSIC Menurut Webster dictionary, secara umum forensic
diartikan sebagai “.. that which is presented in a public forum”. Secara khusus, ketika seorang professional engineer
memberikan kesaksian sebagai saksi ahli (expert witness) di depan pengadilan atas suatu masalah engineering yang menyangkut kepentingan masyarakat dan terkait erat dengan keahliannya maka engineer tersebut sedang bertugas sebagai forensic engineer.
Pada kesempatan itu forensic engineer tersebut
haruslah dapat menjelaskan permasalahan secara obyektif, logis, faktual, netral, tidak bias dan menggunakan bahasa yang mudah dimengerti orang awam tentang cara melakukan investigasi untuk mendapatkan temuan-temuan, teknik evaluasi dan analisis, hasil evaluasi/ analisis, kesimpulan, pendapat dan rekomendasi.
GAMBARAN UMUM FORENSIC ENGINEERING Ruang lingkup yang ditangani forensic engineering, sangat luas dan berikut ini disajikan beberapa hal yang terkait: The most prominent elements are: • investigation, • evaluation and • service as an expert witness Involving :
• court – insurance – owner – contractor – consultant – police – public – government
Possible unexpected cases that result in accident
or structural collapse: (1) During design stage Misinterpretation of codes, design criteria, or design concept Misuse
of
Computer
Softwares
(input
preparation, assumptions, model used, and result interpretation) Miscalculation
(2) During construction Accidents due to inappropriate construction method Poor quality of resulted works Collapse (3) During operation (in service) Accidents, Failure or Collapse due to misoperation/management, poor maintenance or structural degradation Overloading. Corrosive or aggressive env. Earthquake , wind loading Fire , high/low temperature Vibration, repetitive load, blast
Fatigue / fracture Weathering Flood & Scouring Function change
CAUSES OF DEGRADATION In general there are at least 8 causes that makes a bridge experiences degradation: (a) dynamic nature of traffic & wind loadings, (b) fatigue/fracture, (c) overloads, (d) thermal cyclic loading, (e) aggressive and/or corrosive environment, (f) earthquake induced forces, (g) ageing, and (h) flood and scouring.
Overloading & Corrosive/aggressive env.
Earthquake & Fire Loading
Repetitive, blast loading, fatigue/fracture
Weathering & Scouring/flood
Ageing
Outdoor environment • • • •
Wet & dry Humidity UV - radiation Weather
Material deteriora tes naturally
CORROTION IN MARINE ENVIRONMENT
Marine
Hasil core drill
Corrosion : MARINE ORGANISM
Guidelines for forensic engineers
• Avoid conflict of interest • Only take assignments you are competent to perform • Consider the opinions of others before you render
your own • Get all the information, don’t rely on assumptions • Establish the standard of care for the appropriate time and place
• Respect the confidentiality of your client • Be dispassionate and objective at all times • Terminate the assignment if you are not allowed
to conduct the full inquiry • Terminate the assignment if the fee is being used to bias your opinion
Lingkup kasus yang ditangani sangat luas, sejak tinjauan
aspek investigasi, evaluasi, dan menjadi saksi-ahli, sampai tinjauan aspek penyebab accident/failure/collapse yang dapat terjadi pada masa perancangan, masa konstruksi, maupun masa operasi sesuai fungsinya yang mencakup rentang waktu sangat panjang (selama masa layan rencana struktur, yang lazimnya diambil lebih dari 50 tahun). Obyek yang ditangani forensic engineering selalu terkait
dengan infrastruktur yang sudah jadi (existing infrastructures) atau yang sedang dalam masa konstruksi.
Tidak seperti civil engineer pada umumnya, dimana
perencanaan (planning), perancangan (design) dan analisis struktur-baru berikut metode konstruksi dan manajemen proyek merupakan bekal utama yang harus dikuasainya, pada forensic engineering selain bekal yang telah disebut sebelumnya juga dituntut untuk menguasai: a) penggunaan berbagai instrumentasi dan peralatan tes distruktif maupun non-distruktif, b) teknik-teknik evaluasi kinerja existing structures di lapangan,
c) metode analisis-ulang existing structures dengan data saat itu (berupa material properties yang sudah mengalami degradasi karena berbagai sebab), d) metode perawatan, e) metode repair/strengthening existing structures beserta repair materials yang digunakan, dan
f)
pengetahuan yang cukup tentang berbagai peristiwa penyebab keruntuhan struktur di masa lalu dan pengalaman dalam menangani kasus sejenis.
Dalam lingkup yang lebih sederhana (tidak terkait dengan pengadilan), seorang forensic engineer juga mampu menangani permasalahan yang muncul dalam masa pengelolaan, pengoperasian, dan perawatan existing infrastructures, maupun masalah evaluasi teknis untuk menilai kelayakan-pakai suatu infrastruktur selama masa layannya dan metode perbaikan/ perkuatan (repair/strengthening) bila perlu.
Elective Courses & Practical Experiences
Table 1 : CE 5806: Syllabus Forensic Analysis & Condition Assessment of Civil & Mechanical Infrastructure NO
TOPIC
1
Course Overview and Introductions (video)
2
Infrastructure inspections (video) (Chapter 1: NDE)
3
Introduction to investigation of failures due to soil Expansion and Assignment No. 1: Paper on Expansive Soils and/or Structural collapse. Read: Guidelines: Chapter 1
4
NDE Presentaions (video) & Dye Penetrant NDE (Chapter 2: NDE)
5
Expansive soil failure examples and procedures. Read: Failures: Foundation and Building Failures.
6
Dye Penetrant NDE (Chapter 2: NDE)
7
Hyatt Regency, Newport Centre Mall, the promenade, and ethics Questions Raised. Read: Guidelines: Chapter 5.
8
Ultrasound (Chapter 5: NDE)
9
Product failure Investigation
10
Oral and Written Presentations-Structures/Soil Failures
11
Oral and Written Presentations- Structures/Soil Failures
12
Ultrasound
13
Introduction to Vehicular Accident Reconstruction and Assignment No. 2: Paper on VAR. Read: Guidelines: Chapter 3
14
Ultrasound
15
Accident Reconstruction Methods and Examples
16
Ultrasound
17
Magnetic Particle Methods (Chapter 3: NDE)
18
Magnetic Particle Methods
19
Var and Ethics Questions Raised
20
NDE of Timber Structures
21
Computer Programs in Accident Reconstruction
22
Oral and Written Presentations-VAR
23
Oral and Written Presentations-VAR
24
NDE of Steel Structures
25
Deposition Testimony and Assignment No. 3: Paper Engineering Etics Read: Guidelines Chapter 6
26
NDE of Masonry Structures
27
Court Testimony. Read: Guidelines: Chapter 7.
28
NDE of Concrete Structures
29
Contruction Law and Building Failures
30
Product Law and Product Failures
31
Ethics in Engineering Practice and Submittal of Paper on Ethics
32
Course wrap up
Table 2: Texts for CE 5806 ** Required texts for CE 5806 – other texts optional
Guidelines**: Guidelines for Failure Investigation, Task Committee on Guidelines for Failure Investigation of the Technical Council on Forensic Engineering, 1989, ASCE, 345 East 47th Street NY, NY 10017-2398 Failures: Failures in Civil Engineering: Structural, Foundation and Geoenvironmental Case Studies, Education Committee of the Technical Council on Forensic Engineering, 1995, ASCE, 345 East 47th Street NY, NY 10017-2398 Forensic: Forensic Engineering: Learning from Failures, Symposium Proceedings, ASCE Technical Council on Forensic Engineering and the Performance of Structures Research Council of the Technical Council on Research, ASCE National Convention, Seattle, Washington, April 7, 1986, Street NY, NY 10017-2398 NDE**: NON-DESTRUCTIVE TESTING, Barry Hull & Vernon John 1988. The MacMillan Press. Reprint 1994. NONDESTRUCTIVE TESTING METHODS FOR CIVIL INFRASTRUCTURES, Edited by Hota V.S. Ganga Rao, Structural Division, ASCE, 345 East 47th Street, NY, NY, 1993.
MANUAL OF FORENSIC ENGINEERING PRACTICE - A SYNOPSIS The practice of Forensic Engineering involves the investigation of performance difficulties of buildings and structures in the broad field of civil engineering. Investigation of failures usually involves an interface with the legal system, most often in the form of expert testimony. The overall purpose of the Manual is to
commit to writing the current state of forensic engineering practice. As such, this document will not be a standard or code but will address the acceptable behavior of civil engineers engaged in the analysis of failures.
The manual is organized into general areas of interest. They are Qualifications, Investigations,
Ethics, Business and Legal. The chapter on Qualifications basically addreses the minimum education and experience requirements for forensic engineers.
The term expert will be dicussed as defined both by the Courts and by the profession. Various aspects of federal and state law will be cited as they apply to the engineers offering expert testimony. Disqualification will also be discussed. The chapter on Ethics in the primary focus of the Manus.
• Defining ethical behavior of the forensic engineer is the goal of the effort. • The ASCE’s Code of Ethics is applied to the forensic engineer • Both the conflict of interest and the
appearance of such are defined and discussed in detail
Sanctioning processes by the regilatory
bodies and the ASCE are presented. The Legal Forum chapter gives a brief overview of the court system as it applies to the construction industry.
Failure Investgation (examples) 2015 Failure Investigation at a Collapsed Deep Excavation in Very Sensitive Organic Soft Clay 2014 Pedestrian Bridge Collapse and Failure Analysis in Giles County, Virginia 2013 Failure Analysis of a Highway Dip Slope Slide 2013 Soil Slope Failure Investigation Management System 2012 Failure Case Studies in Civil Engineering, Structures, Foundations, and the Geoenvironment 2012 Forensic Engineering 2012, Gateway to a Safer Tomorrow 2012 True Cost of Hurricanes: Comprehensive Understanding of Multihazard Building Damage 2011 Investigation and Repair of a Four-Story Building Damaged by Yazoo Clay 2011 Investigation of Bridge Expansion Joint Failure Using Field Strain Measurement 2008 Collapse of Suspended Portland Cement Plaster Stucco Soffit 2006 Collapse of the Quebec Bridge, 1907 2006 Failure Investigation of a Foamed-Asphalt Highway Project 2006 Roof Collapse: Forensic Uplift Failure Analysis 2005 Failure Analysis of Modular-Block Reinforced-Soil Walls during Earthquakes 2005 Investigation of Flood Induced Pipeline Failures on Lower San Jacinto River 2005 Lessons from the Kinzua 2005 Lessons Learned: Failure of a Hydroelectric Power Project Dam 2005 Probability-Based Diagnosis of Defective Geotechnical Engineering Structures 2003 Anatomy of a Disaster: A Structural Investigation of the World Trade Center Collapses 2003 Failure Analysis of 100-Year Old Timber Roof Truss
2003 Fatigue Performance of Modular Bridge Expansion Joints 2003 Forensic Evaluation of Premature Failures of Texas Specific Pavement Study-1 Sections 2003 Investigation of a Sheffield Structural Tile Floor
2003 Investigation on Failure Behavior of Mixed-Species Glued Laminated Timber Beams 2003 Lessons from the Collapse of the Schoharie Creek Bridge 2003 Lessons from the Failure of the Teton Dam 2003 Numerical Evaluation of Load Capacity of Corroded Pipes 2003 Service Learning and Forensic Engineering in Soil Mechanics 2003 The St. Francis Dam Failure 2002 Failure Analysis of Reinforced Concrete Shell Structures 2002 Failure Analysis of Welded Steel Moment-Resisting Frame Connections 2002 American Society of Civil Engineers: A Case Study in Successful Failure Analysis 2002 World Trade Center Collapse—Civil Engineering Considerations 2001 Look at Context Hartford of Civic ColiseumCollapse Collapse 2000 Another Chronology and the Center Hyatt Regency 2000 LookProcess at the L’Ambiance Plaza Collapse 2000 Another Engineering Failure—Hyatt Walkway Collapse 2000 Facade Failures: The Second Time 2000 Failure Analysis Case Study Information Disseminator 2000 Investigating the Cause of Rotted Wood Piles 2000 Investigation of Construction Collapse of Steel Structure of The Post Office Building in Chicago, Illinois
2000 The John Hancock Tower Glass Failure: Debunking the Myths 2000 Preventing Failures of Precast Concrete Facade Panels and Their Connections 2000 Slope Failure in Weathered Claystone and Siltstone 2000 Stone Cladding Failure: The Cause and Consequences 2000 Temporary Bracing Failures during Construction (Fact or Fiction): Case Studies 2000 ―The Hyatt Horror‖: Failure and Responsibility in American Engineering 1999 Investigation into Cause of Failure of Lift Control Panel 1998 A 1995 Bank Erosion Survey Along the Illinois Waterway 1998 Civil Engineering Education Through Case Studies of Failures 1998 Effects of Lateral Ground Movements on Failure Patterns of Piles in the 1995 Hyogoken-Nambu Earthquake 1998 Lessons from the Failure of the LS Hydroelectric Power Project Dam 1998 Nonlinear Dynamic Analysis of Large Diameter Pile Foundations for the Bay Bridge 1998 The Oklahoma City Bombing: Structure and Mechanisms of the Murrah Building 1998 Shaking Table Tests on Seismic Behavior of Quay Walls Subjected to Backfill Liquefaction 1997 Education Begins Responding to the Needs of our Deteriorating and Failing Infrastructure 1997 Failure Mechanisms in Building Construction 1997 Glossary of Forensic Engineering Practice 1997 The Hartford Coliseum Space Truss Failure—A Retrospective
2000 The John Hancock Tower Glass Failure: Debunking the Myths 2000 Preventing Failures of Precast Concrete Facade Panels and Their Connections 2000 Slope Failure in Weathered Claystone and Siltstone 2000 Stone Cladding Failure: The Cause and Consequences 2000 Temporary Bracing Failures during Construction (Fact or Fiction): Case Studies 2000 ―The Hyatt Horror‖: Failure and Responsibility in American Engineering 1999 Investigation into Cause of Failure of Lift Control Panel 1998 A 1995 Bank Erosion Survey Along the Illinois Waterway 1998 Civil Engineering Education Through Case Studies of Failures 1998 Effects of Lateral Ground Movements on Failure Patterns of Piles in the 1995 Hyogoken-Nambu Earthquake 1998 Lessons from the Failure of the LS Hydroelectric Power Project Dam 1998 Nonlinear Dynamic Analysis of Large Diameter Pile Foundations for the Bay Bridge 1998 The Oklahoma City Bombing: Structure and Mechanisms of the Murrah Building 1998 Shaking Table Tests on Seismic Behavior of Quay Walls Subjected to Backfill Liquefaction 1997 Education Begins Responding to the Needs of our Deteriorating and Failing Infrastructure 1997 Failure Mechanisms in Building Construction 1997 Glossary of Forensic Engineering Practice 1997 The Hartford Coliseum Space Truss Failure—A Retrospective
Contoh : Forensic Engineering Consultant PAUL ZAMROWSKI ASSOCIATES, INC. FORENSIC ENGINEERING CONSULTANTS Engineering Investigation & Analysis Failure Reconstruction Civil * Structural * Mechanical * Electrical * Chemical * Metallurgical GENERAL INFORMATION Forensic Engineering: Engineering applied to matters of losses, claims and law. ***** Experience and integrity are the keys to our success in this esoteric field. Since 1972, forensic engineering has been our sole practice. ***** Paul Zamrowski Associates, Inc. is an association of engineers specializing in technical investigation of accidents, failures and disasters. We determine how and why an accident or damage occurred, explore the extent of damage, and ascertain whether a design, manufacturing, construction or service defect was at fault. Plaintiff or defendant, our findings are impartial. Each investigation involves compiling background information, gathering physical evidence, and reconstructing the incident based on sound scientific and engineering principles. Conclusive, supportable opinions focus on theory of liability. Results are presented in clear, concise reports, fully illustrated with diagrams and photographs. All of our associates are courtroom qualified. We pride ourselves in being able to respond to emergencies immediately. As of January of 2009, our experience exceeds 26,000 cases.
Contoh kasus : Civil Engineering Structural Engineering • • • • • • • • • • • • •
Structural failures and analysis; extent of damage; structural integrity Settlement, deflection and creep Earthquake, fire and tornado damage Corrosion Hydrostatic soil pressure; frost heave Lightning damage Roof failures Sink holes Collapses Temporary support structures Evaluation of pre-engineered metal buildings Blasting and vibrations Weather damage: snow, ice, rain, wind and flood
Contoh kasus : Civil Engineering Hydrology & Hydraulics • • •
Floods, wells, groundwater, surface water runoff Sewerage and drainage systems Stormwater detention
Highway Design, Construction and Maintenance
Industrial Engineering and Accidents Metallurgical and Material Analysis: Metals, timber, plastics, masonry, concrete, composites, earth, asphalt, rock and soil
Berbagai kasus Civil Engineering • • •
• • • • • •
Accident Reconstruction Bridge Design, Construction, Rehabilitation and Maintenance Building Codes and Standards Conformance Chemical Engineering Environmental Control Systems Explosions Temporary Support Structures: Scaffolding, platforms, shoring, bracing, underpinning, hoists and cranes Welding Engineering
• • • • • • • • • • • •
•
Civil Engineering Computers Construction Construction Equipment Accidents: Corrosion Cost Evaluation Crane Accidents Electrical Engineering: Fires - All Types: Fuel Tank Ruptures Glass Failures Human Factors - Investigation and Analysis Hydrology & Hydraulics
The Association of Consulting Forensic Engineers •
• •
•
•
•
The Association of Consulting Forensic Engineers (then Association of Litigation Engineers) was founded in December 1982 by a group of seven Consulting Engineers who practiced as Expert Witnesses in Ireland. The Memorandum of Association defines the role of a Consulting Forensic Engineer as a person who undertakes evidential engineering investigations. Members of the Association are Chartered Engineers (or equivalent status) who practise as Consulting Engineers either individually or as Partner in a Practice of Consulting Engineers. The Association of Consulting Forensic Engineers (ACFE) is a company limited by guarantee. It is registered in Dublin No 93152 There are currently about 50 Members throughout the island of Ireland who practise in a wide range of areas. The common thread is that they prepare Expert Engineering Reports and give Expert Engineering Evidence to the Courts and similar tribunals. Most members work in Personal Injury litigation. Some work in the Criminal Courts and some are Professional Arbitrators. Some members specialise in narrow areas whilst others cover a wide range of work. The Association of Consulting Forensic Engineers fulfils an educational role in that it organises an annual seminar on a topical subject or area of Practice. Some of these seminars are restricted to members whilst others are open and are attended by Practitioners in Law, Insurance and related disciplines. In 2006 the Association introduced the 2006 ACFE Bursary Scheme as part of the commitment of its members to promoting the profession of Engineering to school leavers from less advantaged backgrounds. This is an exciting and unique development in the National STEPS Programme to encourage school leavers to study engineering and science of which the ACFE is justifiably proud.
SEMINARS / SHORT COURSES •
Sudden Damage vs. Maintenance Issues in Buildings
•
•
Sudden Damage vs. Maintenance Issues in Buildings helps students distinguish between distress caused by "sudden" movements of a structure (settlement, strong wind, earthquakes, etc.) vs. normal material deterioration or shrinkage. This course specifically discusses hurricane/tornado sudden damage. Case studies illustrate field inspections and ultimate classification of distress. This course addresses residential and light commercial structures. CE Credit: 4 Hours
•
Wind vs. Wave Damage Assessment
•
•
Wind vs. Wave Damage Assessment course expands on our "Sudden Damage" and "Wind Effects" courses, but focuses on hurricanes. We discuss the hurricane formation, types of hurricane-caused damage, and how to differentiate between damage caused by hurricane-induced waves and wind. We use recent case studies like Hurricane Katrina to illustrate inspection techniques and challenges. This is an invaluable educational tool for those working in hurricane affected areas, or seeking to prepare for next hurricane season. CE Credit: 3 Hours
•
Commercial Roofs Damage Assessment
•
Commercial Roofs Damage Assessment provides students with a comprehensive look at the most common types of commercial roofing materials. We take a detailed look at weathering, specifically hail and wind, as applied to commercial roofs. We examine manufacturing, installation, and natural weathering for the primary commercial roofing types: Built-up, Modified bitumen, EPDM, and Other major flat roof systems. Learn how to differentiate between aging and hail, wind, or mechanical damage. Color photos depict the various types of commercial roofing systems and common damage/problems. CE Credit: 6 Hours
• •
Non Distructive Tests
Pulse Ultrasonic Non Destructive Test (PUNDIT)
Vibration measurement
Core Case
Environmental Testing • • • •
•
• •
• • •
Provides a wide variety of equipment and structures designed to duplicate and test in-use conditions. Unlike typical materials testing laboratories, ours often incorporates special test methods and procedures to replicate operational situations, after which our engineers compile and analyze test data to evaluate causes of failure or potential problems. Much of our test equipment is portable, permitting accurate tests in the field. Environmental Test Chamber. This 27 cubic foot temperature/humidity test chamber is designed specifically for product development, quality assurance, research and other applications to determine product resistance to various temperatures from -20° to + 100° C and humidity exposure from 20% to 98%. QUV Testing. Haag can simulate the effects of temperature, moisture and UV exposure on various building elements. Moisture Detection Testing. Used primarily in roof assembly studies, portable equipment is available to determine the presence and extent of moisture. High-Pressure Hydrostatic Testing. Pressures up to 10,000 psi can be generated for hydrostatic testing of pressure vessels, valves and hose assemblies. High-Current Electrical Testing. Equipment is available to test circuit breaker functions and to load-test electrical cables at ratings of up to 1000 amperes. Mechanical Testing. Tensile testing up to 5,000 lbs. for small specimens is available. Haag also is equipped with portable laboratory equipment for metal hardness field testing. Fire and Explosion Testing. Haag utilizes flammable gas detectors, carbon monoxide monitors and pipe leak test equipment for fire and explosion analyses.
KONTROL KUALITAS BETON 1. Bahan susun (air, agregat halus, agregat kasar, semen, aditif, tulangan) pengujian bahan 2. Proses pelaksanaan (sebelum mengeras) campuran beton, proses pencampuran, bekisting, pengecoran, pemadatan, perawatan 3. Hasil akhir (setelah beton mengeras) sampel benda uji, finishing, defect (retak, keropos), repair.
Homogeneity of the concrete • Measurement of pulse velocities at points on a regular grid on the surface of a concrete structure provides a reliable method of assessing the homogeneity of the concrete. • It is useful to plot a diagram of pulse velocity contours from the results obtained since this gives a clear picture of the extent of variations. • It should be appreciated that the path length can influence the extent of the variations recorded because the pulse velocity measurements correspond to the average quality of the concrete along the line of the pulse path and the size of concrete sample tested at each measurement is directly related to the path length.
Concrete Testing Transducer Arrangement
The diagrams show three alternative arrangements for the transducers when testing concrete. Whenever possible, the direct transmission arrangement should be used. This will give maximum sensitivity and provide a well defined path length. It is, however, sometimes required to examine the concrete by using diagonal paths and semi-direct arrangements are suitable for these.
Compressive Strength
Modulus of Rupture (MOR)
Pulse Velocity (km/sec)
Detection of defects (cracks) • When an ultrasonic pulse travelling through concrete meets a concrete-air interface, there is a negligible transmission of energy across this interface so that any air-filled crack or void lying directly between the transducers will obstruct the direct beam of ultrasound when the void has a projected area larger than the area of the transducer faces. • The first pulse to arrive at the receiving transducer will have been diffracted around the periphery of the defect and the transit time will be longer than in similar concrete with no defect. • It is sometimes possible to make use of this effect far locating flaws, etc. but it should be appreciated that small defects often have little or no effect on transmission times.
Estimating the depth of surface cracks
If the first value of x chosen is X1 and the second value X2 and the transit times corresponding to these are T1 and T2 respectively, then
Crack Depth = X1√(4T12 – T 22)/(T22-T12) The equation given above is derived by assuming that the plane of the crack is perpendicular to the concrete surface and that the concrete in the vicinity of the crack is of reasonably uniform quality.
Crack depth (h) = (L/2)(T2/T1-T1/T2)
Detection of large voids or cavities • A large cavity may be detected by measuring the transit times of pulses passing between the transducers when they are placed in suitable positions so that the cavity lies in the direct path between them. • The size and position of such cavities may be estimated by assuming that the pulses pass along the shortest path between the transducers and around the cavity. • Such estimates are more reliable if the cavity has a well defined boundary surrounded by uniformly dense concrete. • If the projected area of the cavity is smaller than the diameter of the transducer the cavity cannot be detected.
Monitoring hardening process Accurately determine when formwork could be removed In prestressed concrete, when prestressing operation can proceed
This facility is particularly useful for following the hardening process during the first two days after casting and it is sometimes possible to take measu-rements through formwork before it is removed at very early ages. This has a useful application for determining when formwork can be removed or when prestressing operations can proceed.
PERALATAN INVESTIGASI
Alat uji bahan : a. Alat uji tidak merusak (non-destructive apparatus) – mekanik, optik, kimia, elektronik, dinamik, termik, suara b. Alat uji merusak (destructive apparatus) mekanik, optik, kimia, elektronik, dinamik, termik
Alat uji Struktur : a. Alat uji statik b. Alat uji siklik (kuasi statik) c. Alat uji dinamik
10/2/1980
103
Non Destructive Apparatus – Elektronik/ Mekanik 1. 2. 3.
4.
5.
Caliper (mengukur dimensi elemen struktur) Schmidt hammer (mengukur kuat-tekan beton, fc’) Ultra Sonic Pulse Velocity meter /UPV mengukur modulus elastisitas (Ec), kuattekan (fc’), kedalaman retak, ada/ tidaknya keropos beton Crack Microscope (mengukur lebar retak dengan ketelitian 0,01 mm) Rebar Locator (mengukur tebal selimut beton, posisi dan diameter tulangan) 10/2/1980
5
4 3 2 1
A. Alat Uji Bahan 104
Non Destructive Apparatus – Elektronik/ Mekanik
1.
2. 3. 4. 5.
Permeability meter (alat ukur permeabilitas beton dan kekedapan udara ) Pompa hisap udara Jarum suntik air Selang air/ udara Pipet tiup udara Penyumbat udara/ air 10/2/1980
2
3
4 1
5
A. Alat Uji Bahan 105
Non Destructive Apparatus Elektronik
Chloride Test
1.
Probe (berupa bahan sensitif terhadap aliran listrik Indicator (penunjuk tegangan listrik yang mengalir di antara permukaan beton dan baja di dalamnya Stick (tongkat penggerak probe dan indicator)
2.
3.
10/2/1980
3
1
2
B. Alat Uji Struktur 106
Half Cell Test Kits Deteksi korosi tulangan baja dalam beton Potential Level (µ V)
p-korosi
< -200
95%
-200 ~ -350
50%
-350 ~ -500
5%
10/2/1980
107
Non-destructive Apparatus Elektronik 1.
2.
3. 4.
5.
Probes/ sensor & Indicator Inclinometer (mengukur kemiringan 5o) Accelerometer (mengukur percepatan) Velocity meter (mengukur kecepatan) Conditioner/ Indicator (penguat sinyal) Digital Ph Meter & 10/2/1980 Thermometer
B. Alat Uji Struktur 1 4
4
4 5
4 4 2
3
2 108
Loaddisplacement Apparatus Elektronik
A. Alat Uji Struktur 2
1 1.
2. 3.
4.
Load cell (Control - 200 ton) LVDT (50 - 200 mm stroke) Indicator (TC 31K manual/ automatic recording system) Thermocouple and digital indicator (tipe K 1200 C) 10/2/1980
4 3
109
Non Destructive Apparatus – Elektrik/ Elektronik 1.
2.
3.
Mechanical Exciter (penggetar, mengukur frekuensi alami struktur) Speed controller (perubah frekuensi getaran untuk mendapatkan frekuensi alami dan redaman) Balok Uji 10/2/1980
B. Alat Uji Struktur 1
3
2 110
1.
2.
3.
4.
5.
Non Destructive Apparatus Elektronik Sound and Ground Vibration Microphone (mendeteksi intensitas suara dalam desibel) Conditioner (penguat getaran dan menyimpan / meneruskan ke peralatan lain spt komputer/ perekam) Printer (mencetak data hasil perekaman) Accelerometers (dalam arah x, y dan z) Pelengkap lainnya 10/2/1980
1 4 3
5
2
B. Alat Uji Struktur 111
Static & Dynamic Apparatus Elektronik
1. 2.
3.
4.
Loadcell & Indicator Loadcell (25 – 200 ton) Low temperature gauge (mengukur temperatur s/d 100o C) Data logger (penyimpan data 500 kanal) Strain indicator (pengukur regangan digital) 10/2/1980
B. Alat Uji Struktur 4
1
3
2
112
Semi Distructive Apparatus – Mekanik/ Elektrik Corecase 1. Core stand (pemegang posisi dan penekan corebit) 2. Core bit (mata bor berbentuk pipa untuk mengambil contoh silinder beton, diameter 3,5 / 5 / 8 cm) 3. Water pump (pompa air pendingin) 4. Hand drill (pemutar core bit) 5. Pliers (penjepit / pengambil silinder) 10/2/1980
A. Alat Uji Bahan
1 3
5
2 4 113
Contoh hasil core case
1.
2.
3.
4.
Semi Destructive Apparatus Mekanik Coredrill Rotating machine (mesin pemutar core bit) Adjuster (roda penekan core bit) Core bit (diameter 100 – 150 mm) Flexible cooling water hose (pipa air pendingin) 10/2/1980
A. Alat Uji Bahan 2 1
4 3
115
Falling Weight
Deflectometer (FWD) 14 tf
Mengukur bearing capacity rigid/flexible pavement 10/2/1980
117
Heavy Weight
Deflectometer (HWD) 24 tf
Mengukur bearing capacity rigid/flexible pavement 10/2/1980
118
References Guidelines**: Guidelines for Failure Investigation, Task Committee on Guidelines for Failure Investigation of the Technical Council on Forensic Engineering, 1989, ASCE, 345 East 47th Street NY, NY 10017-2398 Failures: Failures in Civil Engineering: Structural, Foundation and Geoenvironmental Case Studies, Education Committee of the Technical Council on Forensic Engineering, 1995, ASCE, 345 East 47th Street NY, NY 10017-2398 Forensic: Forensic Engineering: Learning from Failures, Symposium Proceedings, ASCE Technical Council on Forensic Engineering and the Performance of Structures Research Council of the Technical Council on Research, ASCE National Convention, Seattle, Washington, April 7, 1986, Street NY, NY 10017-2398 NDE**: NON-DESTRUCTIVE TESTING, Barry Hull & Vernon John 1988. The MacMillan Press. Reprint 1994. NONDESTRUCTIVE TESTING METHODS FOR CIVIL INFRASTRUCTURES, Edited by Hota V.S. Ganga Rao, Structural Division, ASCE, 345 East 47th Street, NY, NY, 1993.
References • Krishnamurthy, N. (2007). Forensic Engineering in Structural Design and Construction. Structural Engineers World Congress. Bangalore, India. • Specter, M.M. (2002). Forensic Engineering Curriculum Committee Summary Report l. National Academy of Forensic Engineers (NAFE).
