Litigation Support for Masonry Brick Screenwalls

This project consisted of conducting an investigation into the cause(s) of the observed deterioration of brick perimeter screenwalls in North Texas. The brick masonry units were imported into the United States. Distress observed included cracking, crumbling, deterioration, fading color, and warping. Among the areas investigated were the manufacturing processes, quality control, and adequacy of the specification requirements for the masonry units for their intended purpose. Findings from testing performed indicated that the masonry units did not meet the requirements for durability in a North Texas environment. Among other causes, the firing process during manufacturing most likely affected the durability and performance of the brick in service. CA served as an expert witness, indicating that lack of understanding, confusion, and relaxed implementation of the industry standards for materials in the masonry structures contributed to problems in certifying the quality of the bricks.

NDT Services at a Distribution Center Concrete Pavement Parking Lot

CA conducted an investigation to determine the cause(s) of the distress in the exterior concrete pavement at a distribution center facility in Houston, Texas. The investigation consisted of a comprehensive assessment of the structural integrity of the pavement using destructive and non-destructive testing evaluation techniques as well as the excavation of pits for geotechnical exploration and testing in order to evaluate the as-built soil stabilization methods. Non-destructive testing services provided on this project included ground penetrating radar scanning and relative elevation surveying. Other activities included the evaluation of the original concrete pavement design and assumptions, performance of a life cycle analysis, performance of service life calculations given the actual usage of the pavement, and review of construction related issues. CA also developed recommendations for the repair and remediation of the concrete pavement system.

Seismic Analysis and Design Review of a Power Plant Chimney

A 460 ft. tall reinforced concrete chimney for a power plant was designed under strict loading parameters including the effects of seismic forces. CA was asked to review the design of the chimney to assure it had been designed for the appropriate loads including seismic, wind, and dead loads. CA performed a finite element analysis of the chimney to determine the in-service stresses experienced by the chimney for various load combinations. Furthermore, CA reviewed the original and as-built plans and drawings, original design calculations, and analyzed the design procedure. CA determined the appropriate design procedure and loading conditions and assessed the addition of structural fiber reinforced polymer reinforcement to the as-built structure to provide supplemental stability and capacity.

Repair and Rehabilitation of a Post-Tensioned Parking Garage

A two story, cast-in-place post-tensioned concrete parking garage cut into the side of a slope provided a parking area and structural support for a major grocery store. The second floor of the parking garage was level with the surface parking area adjacent to and in front of the grocery store. Issues investigated were related to water intrusion, concrete cracking, foundation performance, retaining wing wall movement, loss of subgrade support, jointing, construction defects, moisture management, and performance of the post-tensioned beams.  These issues were investigated to determine any possible impacts on the long-term performance of the structure. CA performed, among other things, a detailed condition assessment of the structure, review of construction related documents, drawings, and plans, and a structural analysis and evaluation of the post-tensioned structure. CA successfully determined the causes of the concerns and developed recommendations for repair and rehabilitation of the structure to restore its performance.

Lock and Dam Concrete Mix Design

The Montgomery Point Lock and Dam project consisted of a lock and dam in the lower White River which is part of the McClellan – Kerr Arkansas River Navigation System. In 1995, the design team of this Corps of Engineers lock and dam project was awarded “Project of the Year” by the local chapter of the American Society of Civil Engineers. CA provided consulting engineering services regarding constructability issues, troubleshooting concrete related problems, and the evaluation and optimization of the mass concrete mix design, materials selection, and construction procedures. The mass concrete mix proportioning and placement was attained through the innovative use of supplementary cementitious materials and optimization of the concrete production techniques.

Litigation Support: Slab-On-Grade Distress at an Industrial / Manufacturing Facility

This manufacturing facility consisted of an approximately 200,000 sq. ft. cast-in-place reinforced concrete industrial warehouse floor used for manufacturing and distribution of manufactured products. CA performed a comprehensive condition survey, sampling, petrographic examination, and assessment of the condition and serviceability of the slab-on-grade floor in order to serve as a construction expert witness for this project.  CA’s condition survey included determining the cause of the observed distress in the form of random cracking, delaminations, and control joint deterioration. CA’s litigation support also included, among other things, evaluating the engineering design and specifications, plans and drawings, construction procedures, quality control practices, and concrete materials and their proportions.

Non-Destructive Testing Services at Dos Hermanos Bridge

The Dos Hermanos Bridge structure, built in 1981, is one of the two ground-level links between the Islands of San Juan and Puerto Rico. As a result of the severe marine environment exposure conditions, a few years after its completion, the bridge showed signs of early deterioration including severe corrosion of the concrete reinforcement in both the cast-in-place and the precast, prestressed structural members. CA performed a field condition survey and assessment of the structural integrity and safety of the structure including, among other things, destructive and non-destructive concrete testing, chloride ion content testing to determine the chloride ion penetration into the concrete, and cover meter scanning to determine the location of existing reinforcement. Furthermore, a service life cost estimate analysis and predicted service life expectancy was prepared based on various modeling techniques considering the in-service conditions, the implementation of different concrete restoration and rehabilitation techniques, and the actual properties, characteristics, and performance of the concrete.

Assessment of a Cast-In-Place Post-Tensioned Concrete Parking Garage

A four story, cast-in-place concrete parking garage consisting of an elevated pan-joist slab system framed by post-tensioned concrete beams provided a parking area and a structural frame foundation for a three story commercial office building. The elevated ramps for the parking garage exhibited distress in the form of full depth cracking in the elevated slabs parallel and adjacent to the post-tensioned beams and perpendicular to the longitudinal direction of the intermediate joists allowing for moisture migration and efflorescence to form on the underside of the elevated slab along the length of the cracks. CA performed, among other things, a detailed condition assessment of the structure, including crack maps of the entire parking structure, a review of drawings and plans, and a structural analysis of the post-tensioned beam and joist framing system accounting for their support and restraint conditions. CA determined the causes of the observed distress and developed recommendations for concrete crack repair and remediation of the reinforced concrete structure.

Best Practice Recommendations for Storage of Manufactured Aggregate

CA was retained for the investigation into the alleged environmental damage caused by the handling and storage of manufactured aggregate in the Dominican Republic. All of the material testing reported by the different independent testing agencies confirmed that the raw materials were nonhazardous, non-toxic, and did not represent a danger or hazard to the environment. Visual inspection of the alleged affected areas at the ports of Manzanillo and Arroyo Barril revealed no evidence of distress to the adjacent waters including mangroves and bay shoreline, nor to the adjacent vegetation. CA concluded that manufactured aggregate being stored and/or used at the ports of Manzanillo and Arroyo Barril was non-hazardous. However, there were some deficiencies in the handling, storage, and/or installation of this material at both facilities that needed to be addressed to comply with industry standards for these activities. CA recommended that, in order to ensure the long-term benefit of the cargo storage and truck parking/staging area, the entire area be compacted, re-graded, surface sealed, and that a granular wear course be installed to prevent excessive surface wear and provide and act as a dust suppressant during traffic.