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Forensic Investigation of Exterior Brick Masonry Deterioration

Carrasquillo Associates investigated widespread distress in exterior brick masonry at two residences in Midland, Texas. CA reviewed, evaluated, and synthesized extensive literature pertaining to brick mineralogy and deterioration mechanisms in order to fully understand the many facets and possible root causes of the observed distress and ongoing mechanisms of deterioration. CA conducted multiple site visits to study, observe, and document the brick masonry deterioration and to obtain numerous brick samples from the exterior residential façade and landscaping features. Several brick samples were subsequently tested for physical properties according to ASTM standards, including absorption and compressive strength. The chemical composition and mineralogy of several specimens were studied using x-ray fluorescent (XRF) and x-ray diffraction (XRD) techniques in order to comprehensively investigate the types of raw materials used in production and to assess the degree of vitrification achieved during brick firing. This project provides an example of CA’s expertise in deciphering the contributing players in material degradation, such as brick masonry deterioration, and displays CA’s ability to manage material testing through multiple laboratories for one particular study or project.

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Forensic Engineering Investigation & Analysis of Bridge Overlay Failure

The Pulaski Skyway Bridge Project consisted of a steel truss bridge supporting a concrete bridge deck with repairs where the top 1.5 inches of concrete bridge deck was replaced with a latex modified concrete topping along the entire length. Shortly after, the repairs began to exhibit premature failure in the form of reflective cracking around the perimeter of the repaired area, then debonding, followed by cracking of the patch repair material causing eventual potholes in the bridge deck. CA’s investigation involved, among others, review of daily log reports, expert reports, and other relevant documents, and a site visit during which a visual condition survey was performed to determine the cause(s) of the observed premature patch repair failures in the bridge deck.

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Structural Analysis & Investigation of Retaining Wall Failure in Houston

CA was retained to investigate the failure of a retaining wall at a refinery in Houston, Texas, assess the original design and structural adequacy of the wall for its intended purpose, and to determine the cause(s) of the failure. CA’s investigation consisted of reviewing and evaluating construction related documents, including plans and drawings, contract documents, review of legal documents and correspondence, review of expert reports submitted by all parties, review of structural plans and a structural analysis of the structure.

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Forensic Investigation of Light-Rail Track

The project consisted of cast-in-place, concrete pavement, light-rail track sections at road intersections in Seattle, WA. The pavement system at the road intersections consisted of a bonded overlay system made up of 12 in. thick portland cement concrete pavement bottom layer with a 5 in. thick bonded topping layer. CA was retained to investigate and determine the cause(s) the observed the distress which consisted of hairline cracking in the bonded topping layer of the pavement. CA’s investigation included the review of construction documents and several site visits to perform detailed condition surveys including photographic documentation. CA determined the cause of the distress and recommended repair and remediation options.

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Continuously Reinforced Concrete Pavement Interstate Highway Concrete Crack Repair

This project consisted of conducting a forensic investigation into the cause(s) of the observed random cracking in the continuously reinforced concrete pavement (CRCP) highway sections of Loop 375 in El Paso, Texas. During this investigation, CA conducted a visual inspection of the CRCP sections exhibiting distress, performed an examination of the concrete pavements being investigated, reviewed reports from other investigators, evaluated the concrete production records, and reviewed construction related documents including weather conditions and construction daily reports. The observed distress consisted primarily of random plastic shrinkage cracking. Findings indicated that high evaporative weather conditions, lack of protection of the concrete surface, and poor concrete curing practices contributed to the distress observed. Partial depth and full depth cracks were repaired at CA’s direct using a high molecular weight methacrylate crack sealer. Removal and replacement of the distressed concrete was not necessary.

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Assessment of a Continuously Reinforced Concrete Pavement Interstate Intersection

This project consisted of conducting a forensic investigation into the cause(s) of the observed random cracking and poor quality finished surfaces in the continuously reinforced concrete pavement (CRCP) highway intersections along sections of Loop 375 in El Paso, Texas. During this investigation, CA conducted a visual inspection of the CRCP sections exhibiting distress, performed a petrographic examination of concrete cores obtained from the pavements being investigated, reviewed reports from other investigators, evaluated the concrete production records, and reviewed construction related documents including weather conditions and construction daily reports. The observed distress consisted primarily of poor quality finished surfaces and random plastic shrinkage cracking. Findings indicated that high evaporative weather conditions, lack of protection of the concrete surface, and poor concrete curing practices contributed to the distress observed. The distressed CRCP highway sections were removed and replaced.

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Tennis Court Complex Forensic Engineering Investigation

CA was retained to perform a structural investigation and determine the cause(s) of the distress in two tennis court facilities located at a junior high school and high school in South Texas. To accommodate construction on expansive soil conditions, the structural system of the tennis courts was comprised of precast concrete hollow core planks (HCP) with a 3 inch concrete topping slab supported by cast-in-place reinforced concrete piers. Shortly after construction the owner noticed distress in the form of cracking and spalling along joints in the playing surface of the tennis courts. It was determined that the cracking was reflective cracking propagating from the longitudinal and transverse joints between HCPs which also resulted in localized spalling of the topping slab. CA’s investigation into the problem consisted of, among others, review and evaluation of construction related documents, review of third party repair options, review of expert reports, review of plans and drawings, detailed condition survey and elevation surveys, exploratory coring to assess the details of the jointing between HPCs, structural analysis of the tennis court system, design of a repair alternative, as well as several site visits to the structures. Through the forensic engineering investigation, CA was able to determine the cause(s) of the distress and provide the client appropriate remediation procedures.

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Foundation Crack Repair of High School in Texas

CA was retained to determine if the alleged movement of the reinforced concrete slab-on-grade foundation at a high school was the result of construction related activities and to develop recommendations for restoring the facility. Shortly after the school’s completion, the owner reported deficiencies including, but not limited to, movement of the slab-on-grade foundation which caused distress consisting of cracking and/or separation of drywall panels, out-of-plumb doorways, and out of level floors. CA’s investigation included the review and evaluation of construction related documents, multiple site visits including a detailed condition survey and relative elevation surveys of the school. Through the investigation, CA was able to determine the cause(s) of movement and develop a mitigation procedure to minimize any future movement and restore functionality of the facility.

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Mud Slab Movement at a Cold Storage Distribution Facility

CA was retained to determine the cause(s) of the movement of a mud slab at a refrigerated warehouse facility in Dallas, TX. The mud slab was a constructed as a 3 in. concrete slab-on-ground to house the refrigeration lines of the warehouse. Prior to placement of the 9 in. thick reinforced concrete slab-on-grade above the mud slab, vertical movement of the mud slab was observed. CA was retained by the General Contractor to determine the cause(s) of the movement and provide recommendations in order to allow construction to continue. The forensic investigation, which included communications with the client, site visits to the facility, a condition survey, soil borings, slab elevation surveys at various points in time, and review of geotechnical reports and construction documents, allowed CA to determine the cause(s) of the distress and allow for construction to continue without having to remove and replace the mud slab.

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Structural Engineer Expert Witness: Sports Car Speedway

In January of 2012, a barrier wall at a race track near Houston, Texas was struck by a vehicle resulting in injuries to a spectator. Carrasquillo Associates (CA) conducted a forensic investigation into the structural integrity of the barrier wall. CA’s investigation and litigation support included review of depositions, photographs, drawings, expert reports and industry standards for vehicle barrier design. In addition, CA performed a structural analysis on the as-built barrier wall and after a site investigation to identify distress and the as-built condition of the wall. CA’s investigation culminated in an expert report where CA was able to determine the injuries to the spectator were attributable to the structural deficiencies in the barrier wall and poor safety practices at the facility. The case was settled in favor of CA’s client.