Journal of Performance of Constructed Facilities

The bridge deck expansion joint is an important element in the functioning of bridge structures. When joints fail to function properly, they can create problems out of proportion to their size. Selection of a good joint for use can create fewer bridge maintenance problems. The purpose of the study was to evaluate the performance of several types of joints currently in use on Indiana highway bridges. The types of joints investigated are compression seal, strip seal, integral abutment, poured silicone, and polymer modified asphalt. The research was accomplished through questionnaire surveys, analysis of Indiana Department of Transportation roadway management data, and expert interviews. The questionnaire survey identified the problems and their causes and the merits and potential improvements of each type of joint. The analysis of Indiana roadway management data ranked the performance of different types of joints based on the deterioration rates estimated by the regression coefficients. The expert interviews investigated the practices of Indiana and its surrounding states regarding the selection and maintenance of joints. Based on the research results, several suggestions were proposed to ensure the longer service life of expansion joints.

A three-story school supported by shallow foundations was affected by an adjacent 12.2-m-deep excavation in soft clay in which the excavation support system was a 0.9-m-wide secant pile wall braced by both cross-lot struts and tiebacks. The school is a reinforced concrete frame structure with exterior reinforced concrete foundation walls. This paper summarizes the conditions at the site and presents correlations among construction activities, measured deformations and distortions, and attendant damage in the school. The lateral ground movements associated with the excavation were monitored with four inclinometers placed around the school. The building movements were monitored with optical survey points established on interior columns, exterior walls and on the roof, and with tiltmeters installed on the exterior foundation walls. The damage to the school mainly consisted of 300 to 500-mm-long hairline cracks in nonload bearing walls. Only a few cracks had widths greater than 6 mm. The school deformed such that the portion closest to the excavation sagged and the remainder hogged. Damage was first observed in the area of sagging when angular distortions reached 1/940 and the excavation was approximately 5.5-m deep. Angular distortions as large as 1/300 were observed at the end of the project. The data suggest that angular distortions had to be less than 1/1000 to preclude any damage to the school.

This forensic study is unique in that it involves a pavement warranty specification. Extensive field and laboratory testing was conducted to determine the cause(s) of longitudinal cracks observed on the surface. Four trenches were cut and removed to allow more testing on top of each pavement layer. The tests found that the stiffness of the foamed asphalt base is higher than that of a typical flexible base. However, the subgrade modulus is low compared with the average subgrade modulus in Texas. Water seeped into two trenches (dug into the road where there were surface cracks) within 20 min of digging. No water was observed in the other two trenches, where there were no surface cracks. The two trenches with surface cracks have lower base density and higher base moisture content than the two with no surface cracks. Based on observations of the trenching and coring operations, the same surface cracks have been detected in the base layer. Cracks up to 150 mm into the base layer have been observed. Although cracks have been observed in the base (and they can be related to lower stiffness and higher falling weight deflectometer deflections), it is difficult to determine if the cause of surface cracks is due to the base layer alone. It is difficult to prove if the layer is responsible for the failure, except by properties listed in the specification. One faulty pavement layer can easily cause the failure of other layers. For warranty purposes, layer-specific failure criteria should be clearly outlined. The base did not meet the gradation specification. The field material was substantially finer than specified. While some specifications may have been violated, there is little evidence to show that the cause of the longitudinal cracking is primarily related to the foamed-asphalt-stabilized base.

In Irbid City, Jordan, foundation designs made before 1983 were based on bearing capacity criteria with a limited knowledge of high shrink/swell soil problems. The use of wide and shallow foundation systems was generally the practice rather than the exception in this area. Lack of structural rigidity and insufficient dead load pressure of the foundation systems used in the Irbid area where soils of high shrink/swell are present often cause serious problems related to the performance of constructed facilities. This paper presents a case study typical of a severely cracked one-story reinforced concrete (RC) building constructed over the expansive clay of Irbid City. The building is founded on a mat foundation (solid RC structural slab) embedded at a shallow depth and bearing directly on expansive clay. It is unfortunate that the high shrink/swell potential of the foundation soil had not been recognized properly in the design stage. Based on field and laboratory investigations, remedial construction for the damaged building was proposed. The proposed remedial construction was performed, and more than 10 months have elapsed since the remedial work was completed, with the performance of the building in perfect condition.