A fire originated beneath a modular fireplace hearth in a newly constructed home, which then spread into the adjacent chase and attic spaces, resulting in the destruction of the residence. The fireplace was installed on a CMU block riser positioned on a wooden subfloor in violation of the manufacturer’s installation instructions. Scene investigators concluded based on fire patterns and witness observations that the fire originated beneath the fireplace hearth and that the first fuel ignited was wood construction in proximity to the hearth. The author was contacted 3.5 years after the fire during ongoing litigation to review and analyze the available information and determine the cause of the fire. This paper examines the cause of the fire based on forensic engineering analysis and testing. Incorporation of analysis of previous similar cases and testing data as well as new testing data are utilized to reinforce the author’s cause determination.

Both supporting cables of a climbing treestand failed when a user stepped onto the stand’s foot platform. Analysis of the failed cables revealed extensive corrosion and selective zinc leaching of the galvanized steel cables due to an electrical connection between the treestand cables and the steel frame. Experimental measurements of corrosion rates were performed through accelerated immersion tests utilizing mass-loss and DC current measurements as well as cyclic voltammetry. Results indicated a ~79% to 300% increase in the rate of corrosion as measured by millimeters of cross-sectional area reduction per year. Flaws in the design that led to the creation of a galvanic cell between the treestand cable and its frame are discussed, and alternative designs are proposed. Finally, the manufacturer’s failure to properly account for anticipated use environment of the treestand in its design while being aware of similar prior incidents as well as their over-reliance on warnings are presented.

Distress observed in the plaster lining and gunite/shotcrete of a pool structure located within a podium slab on the third floor of an eight-story student housing building located in central Texas was determined to be causally related to the gunite/shotcrete mix. The gunite/shotcrete mix combined high alkali Portland cement with siliceous aggregates sufficient to generate alkali-silica reaction (ASR). Additional construction deficiencies associated with the thickness of the pool shell and the clear cover over the steel reinforcement were determined to have exacerbated the distress in the structure. Upon demolition of the pool structure, design deficiencies were subsequently identified in the recessed concrete vault that supported the pool structure. The identified design deficiencies included inaccurate structural design and analysis with finite element modeling software, inconsistencies in the thickness of the floor slab, omission of a shear key at the abutment/connection of the floor slab and the vault walls, and an inadequate amount of bonded, non-prestressed reinforcement in the floor slab. These deficiencies culminated in the demolition and reconstruction of the vault. This paper will explore the different parties involved in the design and construction of the project, the errors that resulted in deficient conditions, and the positions maintained by the different forensic engineering consultants representing the various parties.

Holding the obligation to protect life, safety and welfare paramount required the forensic engineer in this case to notify the homeowner to vacate her new home constructed in an active landslide. The forensic engineering evaluation of a four-year-old home revealed extensive damages caused by active soil mass flow in glacial lake deposit soils and a natural spring that imposed excessive hydrostatic pressure on the front foundation wall. The homeowner remained in the home for nearly four years during the investigations while insurers and their engineers argued over coverage. The structural analysis revealed significant probability of imminent collapse, threatening the safety and welfare of occupants and creating both a compelling necessity and an ethical obligation to notify the homeowner of grave peril to the occupants and their need to vacate and abandon the premises.

The applicable building code provides prescriptive specifications that allow construction of the built environment without the need for design professionals to dictate every aspect of every project; however, the building code does not consider all available materials, designs, and/or methods of construction — nor does it consider possible alternatives or construction variances. Since there is more than one way to accomplish a goal, a forensic investigation should consider the intent and purpose of a prescriptive specification (i.e., the desired performance) in order to determine whether an as-built construction variance is capable of accomplishing the same without adversely affecting a structure. This paper will explore the installation of cement plaster veneer and manufactured window assemblies to demonstrate how construction variances can still meet the intent and purpose of applicable prescriptive specifications. As a result, a true forensic approach to construction defect evaluation should not blindly follow prescriptive specifications. Instead, it should employ engineering analysis and a practical method such as the construction variance evaluation methodology (CVEM) to consider the performance aspects of construction variances before concluding that such variances are construction defects.

Approximately 110 years after the discovery of oil in Louisiana, fourth- and fifth-generation landowners filed a legacy lawsuit to recover damages resulting from alleged environmental contamination of family property from oil exploration, extraction, and storage. As part of the complaint, the descendants claimed that, due to the new technology of the oil industry, their uneducated ancestor could not have had reasonable knowledge and business relationships to fully understand the contracts he signed with oil companies to lease his land for oil exploration. Forensic environmental assessment and hydrology enabled the recreation of the site’s historical land use and its potential for environmental impacts. Forensic analyses utilizing records and sources from disciplines typically not consulted in engineering studies provided essential insight into the origins of drainage alterations and contaminant transport across the site, including family records that demonstrated the plaintiffs’ ancestors had knowledge of (and contributed to) the site’s purported deteriorated conditions.

An open neutral or floating neutral is a condition that occurs when the electrical current passing through the neutral conductor in a multiwire circuit is not balanced. This condition can occur when there is a break in the neutral wire, resulting in a loss of continuity in the neutral. As a result, an imbalance in electrical voltage is created in the electrical system. This paper will discuss the forensic engineering analysis of a residential fire caused by an open neutral. It will discuss in detail how a large tree fell on power lines near the house, fractured a nearby residential utility pole, caused a failure of the neutral service splice, and resulted in the separation of the neutral portion of the service line. It will further discuss how the open neutral resulted in a power strip overheating and caused the fire.