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Pancoast tumours (PTs) are apical tumours of the lung that manifest with a variety of symptoms. Herein, we describe a rare case of a 56-year-old female with a one-month history of persistent left leg pain despite advanced imaging, such as magnetic resonance imaging (MRI), and orthopaedic input, which was focused onto her left knee being the prime cause of her pain. Her non-resolving symptoms prompted her to attend the Emergency Department. A careful clinical examination pointed towards the left proximal tibia being the most probable cause. Basic radiographic imaging (x-ray) of the left tibia revealed a lytic lesion which was later confirmed to be metastatic disease arising from a Pancoast tumour (PT) following further advanced imaging and diagnostics. This case highlights a unique presentation of a Pancoast tumour that, to our knowledge, has never been reported before in the medical literature. A high index of suspicion, careful examination, and investigation were essential to reach this diagnosis.

In Florida, pre-stressed concrete bridges with a hybrid structural configuration, consisting of simply supported girders and continuous deck units providing composite action, are prevalent. In this study, an actual bridge with this configuration is instrumented with embedded vibrating wire strain gages during construction. The axial strain data are utilized to determine the time-dependent pre-stress loss variation and distribution in the pre-tensioned concrete girders used for the bridge. In this paper, however, we discuss the bridge instrumentation and monitoring technique used, and the deduced pre-stress losses obtained from field-measured strains up to 150 days, before placement of the composite slab. A comparison of the measured loss with the estimates of the Precast/Prestressed Concrete Institute (PCI) and the American Association of State Highway and Transportation Officials (AASHTO) indicates that the field-measured pre-stress loss is non-uniform across the girder depth, opposed to a uniform distribution implicitly assumed in most codes. The measured pre-stress variation is used in computing the concrete stress distribution in the girder at different depths within the given cross-section. When compared to the concrete stress from using the PCI and AASHTO suggested losses, the stress distribution resulting fron using the field-measured loss is found to be non-linear, and in most cases higher.

Epoxy is normally used to seal segment joints in precast/prestressed concrete bridges. Historically, it has not always been possible to create a good seal at the joint faces. Two new epoxy applications were tested in this study: a top strip recess at the joint, and a recessed annulus groove around the duct that provides a distinct guide for the proper amount of epoxy applications, top strip and annulus. The beams were post-tensioned with a minimum required prestress force. Tanks placed above the joints were used to measure the seepage of water and joint permeability comparisons. Pressurized water was used to detect cross-grouting between ducts. The top strip provided slightly more seepage resistance than that provided by the current one-face epoxy application technique. This feature also improved alignment problems, segment defects, and epoxy application procedures. The practice of one-face application performed well in both tests, but problems occurred in providing the proper epoxy thickness and clearances. Both features performed well and assisted the epoxy application process in producing a reliable joint equivalent to solid concrete.

Epoxy is used between precast bridge segments to fill voids on the faces, keep water and contaminants from seeping into joints, prevent grout from bleeding into joints from posttensioning ducts, and act as a lubricant between the segments during assembly. To create a good seal at the joint faces, two experimental epoxy applications were tested: a top strip recess at the joint formed in the concrete during precasting, and a recessed annulus groove around the duct that provides a distinct guide for epoxy application. Eight beams were fabricated with various combinations of epoxy face applications, top strip, and annulus. Six segments were cast by using match casting. After curing, the beams were posttensioned with the minimum required prestress force. Tanks above the joints were used to measure the seepage of water and joint permeability comparisons. Pressurized water was used to test the cross grouting between ducts. The top strip provided slightly more resistance than did the current one face epoxy application technique and improved alignment problems, segment defects, and epoxy application procedures. The annulus created a watertight seal around the ducts and assisted in aligning the segments and coupling the ducts. The existing practice of one face application performed well in both tests, but problems occurred in epoxy thickness and clearances. The top strip and annulus features eliminated the approximation of edge and duct clearances. Both performed well together and helped the epoxy application process produce a more reliable joint without additional work in casting or erection of the segments.

Nineteen 14 in. (356 mm) square prestressed concrete piles were tested to study the effect of pile embedment on the development length of 1/2 in. (13 mm) diameter prestressing strands. The primary objective of this investigation was to determine the required embedment length of strands in piles, so that the ultimate flexural moment can be developed without strand end slippage. In this study, equations for development length in the AASHTO Specifications and ACI Code were evaluated. Also examined were the general bond slip and the maximum average bond stress at failure.

The paper discusses the testing procedure and strength evaluation of two identical double tee prestressed concrete bridges owned by the City of Tallahassee, Florida. The various elements of each bridge were examined by placing strain or deflection transducers at critical locations along the elements. The bridge was then incrementally loaded to induce maximum stress-strain effects. The data collected from various instruments were used to establish the strength of each component and also to determine the load distribution in the structure. The load testing procedure, data acquisition, analytical model, and comparison of experimental data to analytical results are presented.

In 1997, the Florida Department of Transportation (FDOT) funded a study to evaluate interface bond from full-scale tests. This paper presents results from model and full-scale tests to assess the interface bond between a cast-in-place concrete seal slab and steel H-piles in cofferdams, which are usually required in the construction of bridge foundations over waterways. Three seal slab placement conditions--freshwater, saltwater, and bentonite slurry--were evaluated and results compared against controls where no fluid was displaced by the concrete. The results show that significant bond stresses developed even in the worst placement condition. Recommendations made for revising current values in specifications have already been implemented by FDOT.

In this paper, experimental results are presented from a study conducted to assess the interface bond between a cast-in-place concrete seal slab and prestressed concrete piles in cofferdams. Three different seal slab placement conditions (fresh water, salt water, and bentonite slurry) were evaluated with results compared against controls where no fluid had to be displaced by the concrete. Normal pile surfaces were also studied. Additionally, the situation of soil-caked piles was also investigated. Both model and full-scale tests were conducted. In the model tests, 28 15-cm sq. prestressed sections were used with the embedment depth varied between d and 2d, where d is the width of the pile. 16 specimens were tested in the full-scale tests. The prestressed piles were 36 cm sq., with the emdbedment varied between 0.5 and 2d. Four of the 16 piles were cast with embedded gages located at the top, middle, and bottom of the interface region. The results show that loads were transferred to the piles over an effective area, not the entire embedded depth. Significant bond stresses developed even for the worst placement condition. Recommendations are made for revising current values in specifications.

The appearance of longitudinal cracking and spalling in the web section near the end block of Florida bulb-tee concrete girders have raised some concerns regarding possible problems which may be inherent in the design and construction procedures of the girders. Several factors believed to cause the stress buildup and the cracking were investigated in this study. Results showed that stress accumulation started at the end of the transition section where the web width gradually reduced to 178 mm (7 in.). A wedging effect due to out-of-plane stresses was the most critical factor causing stress buildups in the transition zone. The effect of grout pressure was more severe in ducts with oval cross sections than in round ones.