Forensic Engineering MIDTERMS

to add: chapter 1 of reference, electricity, taylor, composition of mrtar, copper, module 3

Design Errors

flaws in the design phase, such as inadequate calculations or improper structural analysis, can compromise the strength and stability of a structure.

Construction Defects

poor workmanship, improper installation of components, or the use of substandard materials during construction can weaken the structural integrity of a building.

Material Failure

failures can occur due to the failure of materials used in construction, including steel, concrete, or timber. Factors like corrosion, fatigue, or manufacturing defects can contribute to material failure.

Overloading or Excessive Loads

when structures are subjected to loads beyond their capacity, such as heavy machinery or excessive snow accumulation on roofs, it can lead to stress and failure.

Natural Disasters

events like earthquakes, hurricanes, floods, or strong winds can cause severe structural damage and lead to failures, especially if the structures are not designed or constructed to withstand such forces.

Settlement

occurs when a structure sinks or subsides into the ground unevenly. It can be caused by soil compression, consolidation, or the removal of underlying materials, such as mining activities. It can result in structural damage and uneven floors.

Delamination

is a failure mode commonly seen in composite materials, such as laminated composites or concrete overlays. It involves the separation of layers within the material, reducing its strength and integrity.

Erosion and Scour

can weaken the foundations of structures, particularly in water environments. It occurs when the soil or sediment around foundation elements is eroded or washed away by moving water, compromising support and stability.

Chemical Degradation

can weaken structural materials like concrete, steel, or coatings, reducing their ability to withstand loads and environmental factors.

Dynamic Loading

dynamic loads, such as those from earthquakes, wind gusts, or machinery vibrations, can lead to structural failures if the design does not adequately account for these dynamic forces. Buildings, bridges, and other structures need to be designed to resist dynamic loads effectively.

Creep Rupture

is a failure mode in which materials subjected to high temperatures and sustained loads experience gradual deformation and eventually rupture over time. This is especially relevant in applications involving elevated temperatures, like boilers and pressure vessels.

Blast and Impact Loading

explosions or impact events can cause localized or widespread structural damage. Designing structures to withstand blast or impact loading is crucial in high-risk areas, such as military facilities and critical infrastructure.

Inadequate Maintenance

a lack of proper maintenance can lead to structural deterioration and failure over time. Regular inspections, repairs, and maintenance are essential to prevent structural issues from developing or worsening.

Human Error

during construction, alterations, or maintenance can lead to structural failures. Oversight, miscommunication, and negligence can all contribute to structural problems.

Foundation Failure

can lead to settlement or differential settlement, where the structure sinks or tilts due to inadequate soil support, soil erosion, or poor foundation design. This type of failure can result in structural instability and damage.

Cracking

cracks in concrete or masonry structures can develop for several reasons, including structural movement, thermal expansion and contraction, excessive loading, and chemical attacks. Cracking can compromise the integrity of the structure and allow the ingress of moisture and harmful agents.

Buckling

occurs when structural members, such as columns or beams, fail due to excessive axial loads or instability. It often manifests as a sudden, lateral deflection or kinking of the member. Buckling can be caused by insufficient bracing, slender members, or improper design.

Fatigue Failure

happens when a structure or component experiences repeated or cyclic loading over time, leading to the gradual development of cracks and, eventually, failure. It is common in bridges, aircraft, and other structures subjected to dynamic loads.

Corrosion and Rusting

corrosion of metal components, particularly in marine or corrosive environments, can weaken the structure over time. Rusting of steel reinforcement in concrete can lead to cracking and spalling of the concrete cover, compromising the structural integrity.

Overloading

occurs when a structure or component is subjected to loads greater than its design capacity. This can result in deformation, failure, or even collapse. It can be caused by accidents, misjudgment, or changes in usage.

Vibration Induced Failure

excessive vibrations, whether from machinery, wind, or other sources, can lead to fatigue failure or resonance-induced failure. Vibrations can cause damage to structural elements and lead to reduced stability.

Shear Failure

happens when structural members, such as beams or columns, fail due to a combination of shear forces and bending moments. It can result in the sudden tearing or shearing of the material.

Lateral Torsional Buckling

is a form of structural instability that affects beams and girders. It occurs when a beam twists and bends laterally under a combination of axial and bending loads, leading to a loss of stability.

Thermal Expansion and Contraction

extreme temperature fluctuations can lead to thermal stresses in structures, causing cracking and deformation. Bridges, for example, may experience expansion joint failures due to repeated thermal cycles.

Punching Shear Failure

in reinforced concrete slabs or footings, it can occur when the concentrated load at a column or support point exceeds the capacity of the concrete to resist shear forces.

Torsional Failure

occurs when a structural member fails due to torsional or twisting forces. It can affect components like shafts, beams, or columns that are subjected to twisting moments.

Creep Deformation

creep is the slow, time-dependent deformation of materials under a constant load. Over time, it can lead to structural deflection and deformation, especially in concrete and certain metals.

Material Deficiency

material-related failures can result from the use of substandard or defective construction materials, leading to reduced strength, durability, or stability.

Elasticity

the ability to deform with respect to the applied load and regain its original shape when the load is removed.

Plasticity

The ability of non-reversible deformation with respect to the applied load. When a load is applied the body is subjected to deformation; upon removal of the load, it does not return to its original shape.

Ductility

the ability to deform under tensile stress this is often characterized by the material’s ability to be stretched into a wire.

Malleability

The ability to be stretched or deformed or molded into a sheet.

Stiffness

the ability of a material to resist deformation.

Brittleness

the ability to break without significant deformation/develop cracks with respect to the applied load.

Hardness

the ability to resist the scratches, marks, and wear & tear when the body subjected to contact with another body.

Toughness

the ability to resist the shock loads or impact loads

Young’s Modulus

It states that stress applied to the body is directly proportional to the strain induced on the body.

Ductile Yielding

the steel deforms under stress and does not return to its original shape.

Brittle Fracture

the steel breaks suddenly without much deformation.

Buckling

the steel bends or collapses under compressive stress.

Fatigue

the steel cracks or fails after repeated cycles of stress.

Stress Corrosion Cracking

the steel cracks or fails due to the combined effects of stress and corrosive environment.

Creep

the steel deforms slowly under constant stress and high temperature.

Shearing Failure

the steel fails due to a lack of adequate shear resistance between the materials.

Bearing Failure

the steel fails due to excessive contact stress between the plates.

Tearing failure

the steel fails due to excessive tensile stress at the edge of the plates.

True

A building is being acted upon by various factors at any given time: natural forces such as wind and seismic forces, extreme weather conditions, and the weight of the building itself.

Root Cause Analysis

It emphasizes the managerial aspect of system failures and how it can be improved or prevented.

Failure Analysis

It usually connotes the determination of how a specific part or component has failed.

Forensic Engineering

It is the application of engineering principles and methodologies to answer questions of fact.

Priorism

It is the belief that the underlying cases for observed effects are already known.

Expert Witness

For technical statements on an ongoing case relating to a failed building, an Engineering is referred to as what?

Eyewitness Accounts

These accounts are important sources of information but are of high risk to be tainted with opinions.

Forensic

This means that something about the investigation will relate to the law, courts, debates, etc.

Logic

This provides order, coherence to all facts, principles and methodologies of a particular case.

Statementizing

It is a term that refers to interviewing a witness to find out what they know about the incident.

Conclusion

These must be directly based on facts and analysis, not hypotheses.

Technical Expert

These audience would want to know on what facts and observations does the engineer relied, which standards were applied and what methodologies were used for the conclusion

Judge

This person shall be the one to decide if the report can be admitted into evidence

Report Identifiers

It contains the title and date of the report, the names and address of everyone involved and any identifying information

Remarks

A section for the administration that are required to take care of case details

Attorneys

They are the ones who scrutinize every line and word used in the report.

Analysis

It is a section on the investigation report where the facts were being related to one another. This section have technical calculations that are explained to the reader/audience

Purpose

It is a concise statement of what the investigator seeks to find or accomplish

Claims Adjuster

They will use the investigation report to determine whether a claim should be paid under the terms and conditions of an insurance or a contract.

Attachments

This is the section where photographs and descriptions, excerpts from codes and regulations, lab reports and other items relevant to the report.

Background Information

This part contains general information that readers can understand what is being discussed

1911

The text, Principles of Scientific Management, by Frederick Taylor was published.

Calcium Carbonate

Lime or quicklime for the mortar in these buildings was generally obtained by roasting ______ in kilns.