Journal of Performance of Constructed Facilities

An investigation was made into the causes of the collapse of one prestressed concrete roof girder and the cracking of many others at a cement plant. Visual inspection, measurement of cracking and deflection, assessment of in situ strength and design calculations were employed in the appraisal. Overloading of the roof with cement dust was identified as the most probable cause of the failure, although instability arising out of wind uplift may also have been a possibility. The remedial measures proposed for the remaining cracked girders included removal of cement dust and maintenance of the roof in a dust‐free condition, epoxy grouting of existing cracks, provision of externally bonded steel plates for the strengthening of specified panels against shear failure, ensuring proper connection of purlins to girders and the provision of adequate longitudinal bracing for the structure at roof level. A reflection on the causes of failure indicated that misuse during the operational phase was at fault; however, it is argued that a change in design philosophy may have prevented catastrophic collapse.

The paper presents some examples of prestressed concrete double‐Tee (DT) failures caused by Hurricane Andrew. The DT failures were mainly due to the negative moment created by uplift. In some instances a portion of the flange and the stem was torn away; in other cases the DTs collapsed altogether. The DTs were generally subjected to external as well as internal pressure when the overhead doors in these buildings collapsed. Most of the failures occurred in sections with shallower stems. The stress conditions in these DTs subject to hurricane winds are evaluated in the paper using local as well as ASCE design wind loads. In some instances the uplift was large enough for the beams to be airborne, because the anchorage provided was inadequate. Flange failures were also common where DT flanges were used as overhangs with sparse reinforcement. Also, many diaphragm shear connectors pulled out by spalling the small concrete cover provided.

Recently, constructability has received considerable attention from researchers and practicing engineers. Constructability has been defined as the optimum use of construction knowledge and experience in planning, design, procurement, and field operations to achieve overall project objectives (“Constructability” 1986). This paper discusses the evolution of constructability and how programs have been developed to bring design and construction closer to the level of integration once achieved by the master builder. There is a great deal of discussion among industry professionals as to how constructability is related to total quality management and value engineering. This paper conceptually describes these interrelations. In addition, the paper presents a framework to measure costs and benefits related to constructability. By providing owners with this framework, the parameters will be visible and defined, thus removing skepticism as to the measurement process as well as enabling more consistent and uniform results to be obtained. Additionally, these standardized parameters may facilitate developing a means to measure company and industry performance.

Project constructability improvement should be treated as part of an overall continuous project‐improvement process. As such, constructability activities, and results should be continuously evaluated, updated, and improved. This process should include goal setting, self‐assessment, benchmarking of industrywide standards, identification of barriers, and progress measurement. This paper presents a structure of program elements or parameters critical for constructability implementation success and a classification scheme for use in evaluating constructability programs. Industry analysis is used to validate the assessment tool, and the classification system is used to benchmark current constructability implementation practices. Benchmarking study results indicate that the constructability programs of EPC (engineer‐procure‐construct) firms, large‐volume firms, and those involved in industrial projects tend to be more developed, while the constructability programs of general contractors, construction managers, designers, owners, small‐volume firms, and those involved in either the general building or utility sectors tend to be less developed.

Basement failure is one of the most common problems in residential buildings in Ohio. Solving a particular problem of moisture movement through the walls may range from coating the interior of the walls with waterproofing paint for a few hundred dollars to complete replacement of backfill behind basement walls for thousands of dollars. In this paper we classify the signs of basement failures. These signs are evaluated in relation to soil movement on basement walls and the floor slab, lateral forces on basement walls, and chemical and physical reactions on the concrete. Examples of failure signs are flexural deformation of basement structural components, cracking due to shear or flexural stresses, excessive vertical settlements, and moisture movement through the walls. The causes of basement failures are classified into pre‐ and postconstruction causes. Preconstruction causes emphasize errors in design and construction; postconstruction deals with soil movement during occupancy. Causes evaluated in this paper are not exhaustive, but they may be considered as the most common causes of basement failures in Ohio.

Water can migrate through basement walls due to hydrostatic pressure, capillary action, and vapor pressure. The purpose of this paper is to describe a case history of moisture migration through basement walls at a condominium project. The results of subsurface exploration revealed that the upper 0.4–0.5 m of the basement wall did not have a waterproofing membrane. This allowed moisture to seep in near the top of the basement walls. An attempt was made by the developer to stop the leakage through the basement walls by applying a waterproofing membrane to the interior wall surface, but this did not stop the moisture infiltration. The problem could have been avoided if the developer had noticed the height of the waterproofing membrane in relation to the final finish ground surface during construction.