Journal of Performance of Constructed Facilities

The project consists of a five-building motel facility, constructed on a previously mined site in eastern Kentucky. Two geotechnical engineering investigations of the site failed to identify the depth of mine spoil on the site. The first geotechnical engineer recommended the total removal of the uncontrolled mine spoil from beneath the buildings. The second geotechnical engineer recommended only partial removal of the mine spoils directly beneath the footings. The project participants ultimately adopted the second approach for construction and, before completion of the project, settlements of about 0.5 m rendered building 1 unusable. Within five years, building 1 settled about 1 m. In addition, the west end of building 2 had settled about 300 mm. The project developers hired the writer to determine the cause of the settlement and provide testimony in the case. This paper presents the site and project histories, a description of the writer's investigation, a discussion of the results, a description of the dispute resolution processes used for the case, and the writer's suggested procedural changes.

A one-story ranch house was monitored as it underwent static ground subsidence from longwall coal mining. The unreinforced crawl space foundation failed early in the subsidence event. The foundation was not flexible enough to conform to the ground movements, and not stiff and strong enough to ride out the movements. Minimal superstructure damage occurred, although there were serviceability problems, such as stuck doors. Current construction practice may perform much better if the foundation and superstructure were detailed to perform compositely. This could provide the necessary strength and stiffness, preventing both structural failure and serviceability problems.

The purpose of this paper is to describe the causes of distress to the foundation of a residential building, and to discuss the remedial options. The northeast corner of the building had settled excessively. Many cracks were noted on the foundation walls and the basement slab. The north foundation wall had been separated from the floor slab at the rear corner. After completion of a subsurface investigation program, procedural and technical factors causing the failure are identified. One of the factors that contributed to the failure of the foundation included the placement of river bank run gravel overlying a layer of likely uncontrolled fill that was placed during the backfilling of a utility sewer line in the proximity to the failed foundation. The importance of construction monitoring and inspection by qualified personnel as well as close supervision by project manager are verified. After considering the remedial options, a foundation grouting procedure was selected. The pressure grouting was found to be very effective in mitigation of shortand long-term foundation settlement.

Use of broken brick chips as aggregate for making concrete is quite common in countries where natural stones are in short supply. Lack of specification coupled with the absence of a proper quality-control mechanism frequently leads to the use of cheaper and easily available brick chips as coarse aggregate. The high water-absorption capacity of concrete made from such aggregate increases the vulnerability of reinforcement corrosion, and the durability of the structure is impaired. Moreover, the bricks in the coastal region made of locally available soil are likely to contain salt in themselves, and the brick aggregates thus obtained have a higher chloride content. This increases the vulnerability to corrosion in the embedded reinforcement. An investigation into the causes of premature deterioration of a building structure is presented as a case study. An assessment involving laboratory and field investigations has been carried out to identify the causes of deterioration and make a decision regarding an appropriate repair scheme to be undertaken.

This paper outlines individual and major groups of design and construction defects in large buildings in Saudi Arabia and their relative severity. A survey of a randomly selected sample of 30 maintenance contractors and 20 owners from the Eastern Province of Saudi Arabia was undertaken. The survey included 11 major groups of defects and the subdefects in each group. The relative severity effect of each defect on building was assessed and then ranked, based on a severity index by both maintenance contractors and owners. According to owners, 32 defects were rated as “most severe” and 35 defects were rated as “moderately severe.” However, according to maintenance contractors 16 defects were rated as “most severe,” 49 defects as “moderately severe” and two defects as “slightly severe.” It was also found that maintenance contractors and owners generally agree on the ranking of the severity of the defect.

There is a current ASCE Standards Committee activity to develop a standard that provides engineers and designers with minimum recommended design loads for construction. This paper reports on the development of load combinations and load factors (for strength design) for this load standard. Consideration is given to the basis for the selection of load combinations and load factors, the relationship to similar terms in ASCE 7, the limitations (shortcomings) of these preliminary factors and combinations, and suggestions for future work to improve the standard.