Category: Forensic Engineering

Structural A-Frame Rack Failure on a Hauling Flatbed Tractor Trailer

Basic Fact Pattern
  • During transportation of marble and granite stone slabs, a structural failure occurred.
  • The structural failure caused a complete loss of the marble and granite slabs, along with property damage associated with the spilled debris.
  • Alleged improper loading, securement, and/or transportation of the stone slabs.
Investigative Actions Taken
  • Photos of the accident scene were analyzed, along with the geometric configuration of the actual accident location and the speed and direction of travel of the vehicle at the time of the incident.
  • The collected debris from the stone slabs were inspected and analyzed for fracture patterns.
  • The A-frames were reconstructed from the debris by matching the structural weld failures.
  • The ruptures in the tie-downs were also matched back to the accident scene photos to determine the original configurations of the A-frames and the securements utilized at the time of the accident.
Determinations Made
  • The securement and transportation methods utilized were not the cause of the structural failure.
  • The A-frame racks were provided by the material supplier, not the hauler.
  • The A-frame racks lacked adequate design, construction, and maintenance for lateral loads, relying solely on increased securement for stability.
  • The inadequate welds utilized in the A-frame racks design and construction caused the failure, in combination with a lack of adequate inspection and maintenance of the same.
  • The hauler had increased the securement utilized beyond industry requirements, however, this additional redundancy, beyond normal and usual requirements, did not prevent the accident from occurring.
Involved Experts: 

Post-Tree Impact Structural Evaluation

Basic Fact Pattern
  • Large tree strike impact to the roof and stone walls of a historic home.
  • Home reportedly shook during the impact.
  • Tree limbs penetrated the clay tile roofing and the underlying roof structure.
  • The force of the tree strike into the home caused a portion of the trunk to split into two pieces.
  • Cracks and separations were noted throughout the home after the trike strike, including within the mortar joints of the historic stone walls.
Investigative Steps Taken
  • Photos of the tree on the home, as taken prior to the tree removal, were reviewed.
  • Comprehensive inspection of the home, including within the areas broken open by the tree impact, was conducted.
  • Doors and windows were operated throughout the home, along with measurements capable of detecting overall building movement.
  • All cracks, both interior and exterior, were photographed and mapped throughout the home.
  • Cracks were separated via in-field evidence into groupings of recent cracks and historic cracks.
  • Recent cracks were comparatively analyzed against the force load path from the tree strike locations to the ground.
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Determinations Made
  • Structural roof members requiring repair were identified.
  • Wall elements with recent cracks consistent with the transfer of force through the structure from the tree strike were identified.
  • The cause(s) of the remaining cracks were also identified.
  • The overall structure had not experienced any global permanent movement in response to the tree impact force.
  • A scope of repairs was developed in accordance with applicable code requirements.
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Involved Experts: 

Construction Defects Evaluation

Basic Fact Pattern
  • Defendant had installed an asphalt shingle roof and performed pest remediation services on the dwelling
  • The residence had severe damage to its exterior envelope
  • Alleged damages to the residence were the result of poor workmanship of the defendant
Investigative Steps Taken
  • Dwelling was visually inspected
  • Unmanned Aerial Vehicle employed to document areas unsafe for human beings
  • Comprehensive study of building history was performed
  • Detailed code and product analysis was performed
  • In-depth analysis of opposing repair estimate made
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Determinations Made
  • The roofing material was not installed properly and would require replacement
  • The extensive damages to the exterior envelope were historic in nature and not the result of defendant’s faulty workmanship
  • Litigation support services were also provided throughout the mediation process
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Construction Underpinning Failure Damage Evaluation

Basic Fact Pattern
  • Catastrophic damage to a building adjacent to a demolition and new construction site.
  • The adjacent building suffered a severe underpinning failure after the demo was completed and the construction was in progress.
  • The local municipality demolished the adjacent building after condemning it.
  • The insured underpinning contractor had allegedly performed improper excavation and underpinning, including a lack of dewatering, leading to the underpinning failure.
  • There were numerous conflicting elements of testimony and documentation amongst the multiple other involved parties warranting further investigation.
Investigative Steps Taken
  • Severely damaged building was inspected, along with the adjacent construction site.
  • Extensive testimony and documentation was performed, in order to produce a timeline of verifiable facts.
  • Drawings and geotechnical information were analyzed for appropriateness of the underpinning design.
  • On-site photos and daily construction logs were analyzed to determine the work actually performed in the field and the timing of the same.
  • Extensive comparative analysis was performed to determine the truth of the matter.
Determinations Made
  • The engineer responsible for the design and inspection of the underpinning was practicing engineering outside of his technical competence.
  • Both the structural and geotechnical design of the underpinning were insufficient for its intended purpose.
  • The in-field direction provided by the engineer to the underpinning subcontractor directly led to the catastrophic underpinning failure.
  • The engineer also falsified records submitted to the municipality, resulting in reporting to the local engineering board for disciplinary action.
Involved Experts: 

Premises Liability Slip and Fall Evaluation

Basic Fact Pattern
  • Slip and fall on a recently mopped floor in a fast food restaurant.
  • The floor tile involved was allegedly improperly designed, constructed, inspected, and maintained for such a facility.
  • Specifically, the floor tile lacked adequate slip resistance, when tested wet with a BOT-3000e tribometer.
  • The incident was captured on high resolution video surveillance, along with time both before and after the incident.
  • It was also alleged that the plaintiff had not been adequately warned about the presence of a wet floor.
Investigative Actions Taken
  • The details of the incident were extracted from the deposition testimony and documentation of multiple parties.
  • The video surveillance footage was analyzed for:
    • The timing of the mopping and the subsequent drying of the floor.
    • The biomechanics involved in the fall event, as well as the plaintiff’s actions before and after the incident.
    • The actions of others undertaken at or near the incident location, both before and after the incident.
  • In the field, the position of the wet floor sign was re-created, after which analysis of the sight lines during all of the Plaintiff’s movements prior to the incident were analyzed. 
  • Measurements were also taken in the field, along with observations of the cleaning equipment and procedures.
  • Code and construction information was reviewed for the floor tile at issue.
  • Testing performed by others without our knowledge was reviewed against standards for the same.
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Determinations Made
  • The incident location was mopped eight times less than five minutes prior to the incident, with the “greasy substance” felt by the Plaintiff created by her spilled French fries.
  • There was no scientifically credible evidence that any improper procedures had allowed the floor to remain “greasy” after it had just been mopped.
  • The floor tile complied with the applicable building codes and properly applied standards.
  • The tribometry testing performed by the opposing expert was scientifically invalid, due to a lack of adherence to the standards for the same.
  • The opposing expert had also performed improper analysis of alternative codes and standards which did not apply.
  • The Plaintiff had eight separate sight lines where the Wet Floor sign was unobstructed within her field of view, prior to falling reportedly with no knowledge that the floor was wet.
  • The Plaintiff’s slip event initiated as a result of ill-fitted footwear, combined with an accelerated gait pattern (i.e., hurried walking), resulting in a slip event that was not consistent with the 10 other people shown in the video surveillance footage walking over the same incident location successfully while the floor was still wet.

Construction Defect Evaluation on a Multi-Million Dollar Estate Home

Basic Fact Pattern
  • Multi-million dollar custom residence with alleged construction defects in the varying exterior claddings resulting in systemic moisture intrusion and widespread underlying structural damage.
  • Alleged violation of building codes and consumer protection (fraud) statutes.
  • Multiple exterior claddings types and custom doors and windows.
  • Extensive landscaping and post-construction modifications.
  • Full documentation from the builder of the construction process, materials, and methods.
  • Opposing expert cut 15 holes into the building during multi-party destructive testing.
Investigative Actions Taken
  • Available documentation was analyzed in detail with regard to each constructed component.
  • Historic online imagery of the home was used to create a timeline for the post-construction modifications made.
  • The destructive testing program was observed, with a complete interior and exterior inspection completed.
  • Observation was also provided during storm damage repair work performed after the destructive testing had been completed.
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Determinations Made
  • Opposing expert did not properly understand how the construction and post-construction modifications were executed, leading to significant confusion amongst the parties.
  • Construction defects, to the extent they existed, were related to deficiencies in the code requirements and building science understandings of the potential performance of the installed materials within the local climate at the time of construction.
  • Subsequent building science research has proven that these materials cannot physically perform when constructed as they were required to be at the time of construction, leading to specific code changes made since then.
  • Both the moisture intrusion, and the underlying damage, were associated with localized and isolated causal factors, rather than widespread and systemic ones.
  • Re-cladding of the entire residence was not required, and this was already known from testing previously performed, without the need for the excessive destructive testing.

Retail Safety Evaluation of a Watermelon Display

Basic Fact Pattern
  • Trip and fall event in a big box store, involving a watermelon display
  • Multi-million dollar claim following a similar case resulting in a previous $7.5MM verdict against the Defendant one year earlier.
  • Exact fall mechanism was unclear and video surveillance did not capture a good angle of the incident.
  • Same Plaintiff’s attorney as the previous case, but with a different safety expert.
Investigative Actions Taken
  • Deposition testimony and other available documentation was reviewed.
  • Opposing retail safety and biomechanical expert reports were reviewed.
  • Cross examination questions were developed for unqualified opposing safety expert.
  • Research study cited by opposing safety expert was fully reviewed, as well as other research by the same individual, which was not addressed by the opposing expert.
  • Safety policies and procedures were compared to national consensus-based voluntary safety standards.
  • The use of the watermelon display at the time of the incident was compared to the manufacturer’s recommendations for the use of the display, the grocery industry recommendations for the use of the display, and the merchandising use of the same display throughout 15 different retail chains.
  • A key piece of evidence in the previous case was also re-reviewed.
Determinations Made
  • The key piece of evidence in the previous case was falsely presented by the previous expert.
  • The watermelon display, as utilized at the time of the incident, was consistent with industry standards, safety standards, and merchandising in service at competing retail chains.
  • The research cited by the opposing expert did not present the conclusions alleged by the opposing expert report.
  • The alternative merchandising suggested by the opposing expert for this case would have defeated several of the safety features already built into the display, rendering the display less safe, rather than more safe.
Involved Experts: 
  • Benjamin Irwin, P.E., DFE
  • Travis Wells, P.E.

Stains on Sculptures – Multi-Disciplinary Investigation

Basic Fact Pattern

  • A mysterious repetitive staining was discovered on a marble sculptural installation within a construction work zone at a major museum in Michigan.
  • The marble pieces were sculpted using water jetting technology in Spain, after which they shipped internationally on a freight barge in partially open crate containers.
  • The staining was random in nature, but tended to appear in horizontal joints, but not vertical ones.
  • The staining would re-appear over the course of more than one year, but not always in the same locations.
  • Previous experts had speculated about possible moisture entrapment within the marble pieces and/or moisture absorption into the marble during shipping in improper containers.
Overview of Sculpture
Sculpture area under construction
Investigative Sciences Employed
  • The entire sculptural installation was 3D scanned in place in color to document the locations where the staining currently existed, in combination with the joint locations throughout the installation.
  • An infrared scan of the marble surfaces was conducted to determine if patterns of moisture and/or air migration were detectable within the joints of the sculptural installation.
  • A temperature and humidity survey was taken on a grid system within the room to determine if patterns of moisture and/or air humification were detectable within the museum room.
  • Portions of the installation materials that had not yet been installed were sampled for chemical testing, including shavings from the backside of one of the marble pieces and the supporting structural framework, attachment, and lateral anchorage elements.  Shavings of discolored marble were also collected from inside of one of the stained horizontal joints.
  • Historical data regarding the appearance of staining over time from the museum were compared to the Building Management System temperature and humidity readings obtained within the construction zone over time.
Stains between horizontal joints
Back of sculpture

Determinations Made:

  • A lack of complete environmental controls within the construction zone was causing seasonal fluctuations in temperature and humidity, affecting the absorption, release, and condensation of moisture into and out of the marble pieces over time.
  • Environmental conditions present at the time of installation of each individual piece directly affected the timing of when staining would appear within any given marble piece.  Differences between the marble pieces themselves also caused many pieces to not exhibit staining at all.
  • The white marble material contained a soluble salt impurity that was released only in the presence of bulk water.
  • Staining only occurred during the moisture condensation phase of the indoor environmental changes.  Due to variations between the conditioned front side of the sculpture and the unconditioned backside of the sculpture, vapor drive expelled the excess moisture through the joints.
  • Welded stainless steel lateral anchorage plates were embedded into gouges in the stone pieces at the horizontal joints only.  Condensed bulk water collected in the gouges, releasing the salts, interacting with the anchors and/or their welds, thereby forming the colored contaminant, which was then transported through the horizontal joints by the vapor drive, depositing the colored contaminant on the surface of the sculpture.
Involved Experts: 
  • Benjamin Irwin, PE, DFE
  • Everett Lenhart, PE
  • Matt Westrich, PE
Welded stainless steel lateral anchorage plates

Accident Reconstruction – Tractor Truck v Passenger Vehicle

vehicle-damage

Haag Engineers investigated an accident involving a truck tractor and a passenger vehicle which occurred on an interstate highway.

Haag was asked to analyze a multi-vehicle accident involving a passenger vehicle and a truck tractor. Within 24 hours of the accident, Haag Forensic Engineers arrived on the scene and were able to locate and measure pertinent data including tire marks, roadway gouges, liquid debris, and guardrail damage. We were able to determine the paths of the vehicles prior to and after the collision. We investigated the vehicles to document the location and extent of damage that occurred during the accident. Based on our analysis, we were able to determine the path of the passenger car, events prior to collision with the truck, points of impact during the accident, and how this information confirmed our sequence of events. When witness reports were received, they were consistent with our analysis. 

truck-damage
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