Category: Case Studies

Foundation Movement

Haag evaluated possible residential ground subsidence and structural damage at a residence.

Haag was asked to inspect a residence with cracks in the exterior stemwall, interior walls, and ceiling. The house was wood-framed, built in 1940, and had a combination stemwall and pier and beam foundation. It was located in the Tampa Bay area, where sinkholes are common. Haag performed a structural inspection, floor elevation survey, ground penetrating radar survey, foundation excavation and inspection, soil borings, and laboratory testing. Our investigation revealed that the damage was not caused by a sinkhole, but rather was due to a layer of buried peat as much as 11 feet thick. Peat is highly compressible and will continue to compress over time as the organic material continues to decay. Haag recommended underpinning the home’s foundation.

Grain Elevator – OSHA Citation

Haag was asked to evaluate design and installation of a cross-flow grain dryer at an Ohio grain elevator, and address the merits of an OSHA citation related to installation and safety, & evaluate compliance with 29 CFR.

A natural-gas fired, choke-fed, cross-flow dryer was originally installed by the manufacturer in 1997 and had remained substantially unchanged. After a brief visit, OSHA issued citations which stated that the involved dryer was not equipped with “controls that automatically stopped the incoming grain to the dryer when a high temperature condition was detected.” Further, OSHA added that “it was clear the equipment [had] the necessary components to be installed to meet the standard… but it was discovered that the alarm sensor… was never installed.”

Haag reviewed installation and operator manuals provided with the grain dryer and determined that the involved dryer could be installed in one of two configurations – a choke-fed configuration and a reversing-slide gate configuration. For the former, a positive shutdown mechanism for the incoming grain elevator leg was not recommended by the manufacturer. Grain flow into the dryer was stopped by shutting down the discharge metering system during a high temperature alarm, causing the incoming grain to bypass the dryer spout and return to storage. Since the automatic shutdown of the discharge metering system effectively stopped the flow of grain into the dryer, we concluded that the automatic shutdown complied with the requirements of 29 CFR 1910.272. Site visits by Haag and the dryer manufacturer independently verified that all required sensors and controls were properly installed on the involved dryer.

Further, Haag reviewed national consensus standards for emergency shutdowns published by the National Fire Protection Association (NFPA). A key distinction between the NFPA and 29 CFR 1910.272 was that the NFPA required the sensors to “stop the flow of product out of the dryer” while 29 CFR required sensors to “stop the grain from being fed into the dryer.” Haag Engineering evaluated the merits of each standard using Failure Mode and Effects Analysis and other techniques and concluded that the NFPA standard provided greater protection from the anticipated hazards than 29 CFR 1910.272. According to Appendix A of 29 CFR 1910.272, compliance with a national consensus standard that provides equal or greater protection than 29 CFR 1910.272 is considered compliance with the corresponding requirements.

We published a report addressing the alleged installation issues and safety requirements of both 29 CFR and the NFPA. Our analyses had shown that the involved dryer complied with both standards. The matter was ultimately resolved after all citations against the grain elevator were removed

Grain Explosion Evaluation

A large grain dust explosion occurred at a grain company facility. The explosion severely damaged three connected silos and injured six workers, as employees were loading rail cars when the explosion happened, and sections of the bins toppled onto the rai.

On August 13, 2014, a large grain dust explosion occurred at the Coshocton Grain Company facility in Coshocton, Ohio. The explosion severely damaged three connected silos and injured six workers. Employees were loading rail cars when the explosion happened around 4 pm, and sections of the bins toppled onto the rail cars.(1)

The 60-year-old Coshocton Grain facility was a 2.5-million-bushel capacity grain receiving, drying, and storage facility that included three slip-formed concrete storage houses standing more than 100 feet above grade at the bin deck. A single gallery spanned across all three houses; two of the houses had head houses. A tunnel network connected all three grain houses in the basement, and one of the houses to a truck dump building and to several silos across railroad tracks to the south. South of the railroad tracks were five additional concrete silos, four steel storage bins, and several small buildings.

Seven bucket elevators, 12 drag conveyors, 11 belt conveyors, two screw augers, and one tripper directed the flow of grain throughout the facility. In general, the equipment in the basement and ground-level directed flow of grain away from the dumps and bins, and to the boots of the elevators. Elevated equipment directed flow away from the elevator legs to the various silos, bins, dryers, and load out areas of the facility. There were also three dust collectors, a dryer, a truck scale, and a continuous flow scale.

Haag responded to determine the origin and cause of the explosion, which included coordinating with OSHA representatives and salvage efforts.

The explosion caused a large area of the middle house to blowout and the head house to fall to the ground and damage several railcars and railroad tracks. Haag’s original scope expanded to include documentation of the explosion site using 360° photography and scanning (3D laser scanning), evaluation of structural and mechanical damage caused by the explosion, and a cost estimate of the explosion-related damage.

SOURCE (1) NO GRAIN, NO GAIN: COSHOCTON GRAIN, FARMANDDAIRY.COM; HTTPS://WWW.FARMANDDAIRY.COM/TOP-STORIES/NO-GRAIN-NO-GAIN-NEARLY-A-YEAR-AFTER-A-DEVASTATING-EXPLOSION-COSHOCTON-GRAIN-IS-COMING-BACK/265567.HTML, JUNE 2015.)

Involved Experts:

John Z. Wlascinski, Principal Engineer, Houston Branch Manager, Board Chairman

Ground Surface Dropout at Residence

Basic Fact Pattern

During a site stabilization, a surface dropout occurred below the residential structure causing additional damage to the foundation and walls.

Investigative Actions Taken

Haag performed a geotechnical subsurface evaluation of a residence related to possible sinkhole activity. Our study of the property involved exploratory drilling and sampling, shallow excavation, a geophysical survey and laboratory testing. Our findings revealed highly weathered limestone at depth and formed cavities and voids from soil raveling associated with sinkhole activity.

Determinations Made

Haag recommended a program of deep compaction grouting and shallow chemical grouting to stabilize the building pad. During stabilization, several surface dropouts occurred. Haag quickly responded to develop plans for stabilizing the ground and residential structure. Haag monitored the filling of voids below the foundation and slab with a cement slurry and rapidly implemented a grouting program to treat raveled soils and limit property damage.

Involved Expert:

George Stepanchak, P.E., Engineering and Geotechnical Manager

Hoover Dam By-Pass Bridge Collapse

The Hoover Dam’s By-Pass lifting system, a luffing cableway supported by four towers, collapsed during high winds.

The Hoover Dam By-Pass Bridge was part of the new alignment of U.S. Highway 93 across the Black Canyon between Arizona and Nevada and was located approximately 1,500 feet downstream of Hoover Dam. Total length from abutment to abutment was approximately 1,090 feet. The structure was the first concrete-steel composite arch bridge built in the United States and includes the longest cast-concrete arch in the Western Hemisphere. The Obayashi Corporation and P.S.M. Construction USA, Inc. Joint Venture (Obayashi/PSM JV) was awarded the bridge construction contract by The Federal Highway Administration (FHWA). HDR Engineering, Inc., and T.Y. Lin International were the bridge design team.

For construction of the bridge, the By-Pass lifting system was a luffing cableway as defined by the American Society of Mechanical Engineers (ASME) B30.19 – Cableways. Four lattice towers, each approximately 330 feet tall, were erected on either side of the Colorado River immediately south of the Hoover Dam. Distance between the opposing towers (span) was approximately 2,500 feet. The two cableways extended parallel and along the centerlines of the double highway lanes of the new bypass bridge. Each tower could lean (luff) in the north/south direction to provide lifting capabilities for the load block to reach the entire width of each of the double highway lanes. Lower and upper load blocks were supported by a carriage that was positioned along the spanned length by inhaul and outhaul ropes on the track cables (gut lines).

During high winds on September 15, 2006, the Nevada South tower buckled and collapsed. During the collapse, the falling sections severed multiple support cables of the Nevada North tower causing it to fall to the north. The resulting collapse of both Nevada towers imparted dynamic loading to the two Arizona towers, causing both to fall westward toward the Black Canyon of the Colorado River.

Haag Engineering Co. was retained to determine factors causative of the collapse and evaluate duties and responsibilities of the parties involved in the design, erection and use of the specialized equipment. During recovery efforts, Haag assisted in the design/evaluation of a new cableway system, erection and load testing. The Haag team was assigned to the project from collapse on September 15, 2006 until the connection of the arches in 2010.

The Hoover Dam By-Pass Bridge was sucessfully completed after this set-back, and officially named the “Mike O’Callaghan–Pat Tillman Memorial Bridge”. Opening ceremonies were held on October 19, 2010. The bridge has been a vital to improving traffic on Interstate 93, between Phoenix and Las Vegas and between the United States and Mexico, ever since.

Restoring a Fire-Damaged High-Rise

Fire damaged three floors of an apartment tower; smoke and water damaged the rest. Haag consultants created the plan for setting things right, and for keeping the loss from growing in scope and cost.

The direct fire damage was extensive — three of the nine floors in a Little Rock residential high-rise — and the water and soot damage was comprehensive. All nine floors required expert evaluation and restoration. Haag Construction Consultants became the central figures, working with the adjuster, contractors, and municipal building officials to determine the scope, cost, and timeline for putting things right. That required careful analysis of what could be repaired, what required replacement, and what each would cost. In addition, our Haag consultants were asked to identify potential environmental exposures, especially with regard to indoor air quality and possible improper mitigation practices. Not only did Haag give all the interested parties a complete, clear picture of the loss, we also helped identify tasks that required urgent attention to prevent the loss from growing in scope and costs.

A Storm Overwhelms Dormitories’ Drainage Systems

When the storm drains around the dormitories at a southeastern college proved inadequate in a heavy storm, water entered several of the buildings, damaging flooring and drywall. An inspection by Haag Construction Consultants established what needed to be done to restore the dorms. Then, during the restoration project, a new problem turned up: The flooring material and mastic contained asbestos. The Haag consultants arranged for an abatement contractor to perform the asbestos abatement. Despite this unforeseen complication and the delay it caused, Haag’s oversight helped the college complete the dorm reconstruction in a timely manner.

Construction Consulting Post-Hurricane

The 2017 storm year began with Harvey, the stubborn gulf storm which camped out over Houston and the entire coast of Texas for 7 days in August. Irma and Maria then dealt back-to-back blows to the Caribbean, with property claims activity extending through the Keys into Central Florida.

Haag’s Construction Consulting (HCC) business unit has received of a great deal of activity in all areas of the US affected by the heightened 2017 season. Years out from these storms, Haag Consultants continue to receive new assignments weekly. In addition to our 2017 hurricane work across the mainland, Puerto Rico assignments have continued at a very steady pace. We are now progressing from the initial damage assessment phase into the controversy and litigation phase.

Haag Construction Consulting’s work in Puerto Rico has included hospitals, shopping malls, high-rise office buildings, resort hotels, retail centers, government facilities, and mid and high-rise condos. As with any coastal vacation area, Puerto Rico is heavily populated with mid- and high-rise condos, apartments, and resort hotel properties.

Multi-family or commercial property assignments usually involve Construction Consulting inspection teams of four to eight consultants for anywhere from two to six days to carry out the initial site inspection activities. As the site inspection is concluded, our teams then move to the production of repair estimates and reports, which involves sorting through thousands of site photos and hundreds of pages of scope notes. We translate those notes and photos into a very thorough, supported scope analysis and repair estimate.

The team at Haag Construction Consulting’s work product and quality has led to satisfied clients, which in turn has created additional work in Puerto Rico, and all 2017 hurricane-effected areas.

By Brandon Alaniz, Senior Construction Consultant

Brandon Alaniz is an experienced construction consultant, with more than 15 years in the construction industry. He is responsible for maintenance, and completion of all consulting services and related work product. His emphasis is building reconstruction, restoration, equipment and machinery cost, and remediation cost for the insurance industry. Preparation of construction loss estimates and restoration / remediation management services for losses that are either repaired by the owners and need constant supervision to expedite or losses that require this service to fast-track a project without the need of a general contractor, to insure the favorable / equitable conclusion of a loss. Experience in many forms / types of construction and restoration including; multi-family dwellings, educational, municipal, hotel/motel, and multi-story

Hurricane Shelter Collapse

Haag Engineering was asked to determine the cause of collapse of a hurricane shelter, determine responsible party with respect to subrogation, & evaluate the remaining structure with respect to repairability.

The metal building structure was an indoor sport/event arena that doubled as a hurricane shelter. Approximately 1,400 people had flocked to the shelter for safety before the storm. The metal roof system peeled away as the storm neared, causing most of the building to collapse. All 1,400 occupants survived due to their retreat below the concrete bleachers. Haag Forensic Engineers were called out to determine the primary cause of the collapse, determine who was responsible with respect to subrogation, and to evaluate the remaining structure with respect to reparability. We examined the structure, stewarded required evidence retained for all parties, and identified building conditions that led to the collapse. Our conclusions were provided via open forum presentation during mediation. The accuracy, detail, and reporting of our conclusions in a simple yet complete presentation enabled all parties to quickly understand the facts of the collapse and come to a mutual financial agreement without litigation. The structure was reconstructed after settlement was achieved.

Hyatt Regency Walkway Collapse

Haag Engineer E. Earle Walters discusses the investigation of the collapse of two walkways at a Hyatt Regency hotel.