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Abstract: The dynamic nature of today's construction industry compels construction partners to seek strategies in order to improve performance. Current research introduces a performance evaluation model for construction companies in order to provide a proper tool for a company's managers, owners, shareholders, and funding agencies to evaluate the performance of construction companies. The model developed helps a company's management to make the right decisions. Financial, economical, and industrial data are collected from Egyptian construction companies for nine consecutive years (1992-2000). Five indices (models) are developed: company performance score, economy performance score, industry performance score, performance index, and performance grade. The models developed consider companies in four construction sectors: general building, heavy, special trade, and real estate. These models accommodate the effect of macroeconomic and industry related factors and company size on the performance evaluation. The final outcome of current research is a performance grade, which provides the performance of a construction company. The developed model is validated, which shows robust results. DOI: 10.1061/(ASCE)0733-9364(2007) 133:8(574) CE Database subject headings: Construction industry; Performance characteristics; Egypt; Construction firms; Evaluation; Case reports.

The key to a successful implementation of a build-operate-transfer (BOT) infrastructure project is in-depth analysis of all aspects related to economic, environmental, social, political, legal, and financial feasibility of the project. For these reasons, the analysis of the project feasibility decision needs a technique to include the qualitative decision factors that have a strong impact on the project. This paper aims to introduce a decomposed evaluation model developed to assess the most common significant decision factors that strongly affect the feasibility of BOT projects. The paper describes the viability decision factors that were identified and screened with the assistance of a group of industry experts. This analysis yielded 21 significant factors that would have a certain impact on the feasibility of any BOT project. These factors were classified into three relative categories forming the structure of the suggested project viability model. This model presents a new approach, based on the analytical hierarchy process technique, to evaluate the relationships between decision factors related to project feasibility determination. The new approach has been validated by information obtained from three case studies of BOT projects. The proposed approach to project feasibility evaluation aims to increase the decision maker's ability to determine the factors contributing the most to the viability to the BOT project at hand. DOI: 10.1061/(ASCE)0733-9364(2007)133:1(50) CE Database subject headings: Build/operate/transfer; Infrastructure; Decision support systems; Construction management.

Problems in operating construction equipment in Egypt were perceived as resulting in low productivity. Productivity was considered in this study as a measurement dimension that sufficiently describes operator's performance. The objectives of this study are to provide an analytical approach for identifying causes of productivity loss and evaluating their effects, and to evaluate the performance of equipment operators. The performance ability ratio (PAR) compares the actual productivity against the estimated productivity to demonstrate the amount of loss of productivity and, thus, judge the level of operator productivity. The study was conducted at 11 jobs concerning 11 pieces of earthmoving equipment: three bulldozers, three elevating scrapers, three off-highway trucks, and two hydraulic backhoe excavators. The analysis led to basic conclusions concerning the amount of downtime and its variation according to equipment type, and the average PAR values for operators of the four types of equipment.

The Ameria Tunnel Pumping Station (ATPS) is the main pumping station of the Greater Cairo Wastewater Project. The objective of ATPS is to lift the wastewater for a vertical distance of 32.0 m (from the collection tunnel at approximate mean sea level (MSL) of - 14.0 m, to box culverts at ground level, + 18.0 m MSL) to continue the flow under gravity to the final treatment plant. The ATPS contains eight huge centrifugal pumps, each with a lifting capacity of 3,600 L/s. It is considered one of the highly technological civil engineering works in Egypt, probably the largest installation of its kind in the world. This paper outlines the construction method used to carry out various work elements of such a large civil engineering project. The problems encountered during construction (mainly due to the soil structure and characteristics), and the solutions innovated for these problems are also presented. A call is made for extensive soil investigation to minimize uncertainty and problems during future underground constructions.

Many construction systems have been used to build several highway bridges and elevated roads in Egypt. Recently, the stepping shuttering system has been used in Egypt for cast-in-place concrete bridge. This system is most appropriate for concrete bridges of moderate spans ranging from 40 to 70 m. The stepping shuttering system provides appropriate means to satisfy local needs for concrete bridge construction in an urban environment, practically without infringing on traffic or property below. This paper presents an innovative method of construction that has been used in Egypt for the first time to build the 6th October Bridge extension. Issues regarding the constructability and innovation are highlighted, and the significant aspects during the bridge construction are documented. Also, the difficulties encountered and the lessons learned are thoroughly investigated. In addition, evaluation of the system is discussed in terms of construction cost, schedule, and flexibility. Finally, this paper presents an innovative method that offers substantial opportunity for enhancing constructability of concrete bridges using the stepping shuttering system.

Recent advances in inertial microfluidics designs have enabled high throughput, label-free separation of cells for a variety of bioanalytical applications. Various device configurations have been proposed for binary separation with a focus on enhancing the separation distance between particle streams to improve the efficiency of separate particle collection. These configurations have not demonstrated scaling beyond 3 particle streams either because the channel width is a constraint at the collection outlets or particle streams would be too closely spaced to be collected separately. We propose a method to design collection outlets for inertial focusing and separation devices which can collect closely-spaced particle streams and easily scale to an arbitrary number of collection channels without constraining the outlet channel width, which is the usual cause of clogging or cell damage. According to our approach, collection outlets are a series of side-branching channels perpendicular to the main channel of egress. The width and length of the outlets can be chosen subject to constraints from the position of the particle streams and fluidic resistance ratio computed from fluid dynamics simulations. We show the efficacy of this approach by demonstrating a successful collection of upto 3 particle streams of 7μm, 10μm and 15μm fluorescent beads which have been focused and separated by a spiral inertial device with a separation distance of only 10μm -15μm. With a throughput of 1.8mL/min, we achieved collection efficiency exceeding 90% for each particle at the respective collection outlet. The flexibility to use wide collection channels also enabled us to fabricate the microfluidic device with an epoxy mold that was created using xurography, a low cost, and imprecise fabrication technique. [ABSTRACT FROM AUTHOR]

Compaction grouting is an important soil improvement and underpinning technique that involves injection of a very stiff grout material into the soil. The objective is to displace and compact the surrounding soil without permeating or hydrofracturing it. Compaction grouting has been developed and used almost entirely on the basis of practical experience. The present study proposes a theoretical model that describes the mechanics of the compaction grouting process and rationally considers the different soil and grouting parameters that govern the overall design and performance of the method. The theoretical basis of the model draws from the theory of cavity expansion as well as the conical shear failure above the grout bulb. This model was validated using limited available data. The results indicate reasonable agreement and show a good potential of the proposed model for rationally optimizing the design of compaction grouting operations.

Inadequate and poorly maintained pavement markings are considered to be one of the largest contributing factors to fatal motor vehicle crashes. As a result, it is essential to apply the appropriate pavement marking material for all weather conditions in order to increase public safety and reduce motor vehicle crashes. Building a strategic plan to renew and re-stripe pavement marking is receiving increasing interest from companies/authorities that manage the pavement marking in order to reach the most cost-efficient management plan of the available pavement marking materials. The objective of this paper is to develop pavement marking performance models that predict the condition of different marking materials under various service conditions including weather, traffic and snow removal plans. The developed models are validated and the results show that the average percent validity varies from 87% to 99%. Marking performance is assessed using a condition rating scale, which numerically ranges from 1 to 5 and linguistically from excellent to critical, respectively. Deterioration curves are developed that assess the condition of the pavement marking based on the developed models. They are expected to benefit academics and practitioners (municipal engineers, consultants, and contractors) to prioritise inspection, stripping, and re-stripping planning for various pavement markings. [ABSTRACT FROM AUTHOR]

Canadian municipalities have noted that 59% of their water systems and 68% of their sewer systems required repair. To rehabilitate, replace or construct a water or sewer pipeline, several methods can be used: open-cut or one of several trenchless technologies (TTs). The selection of the method positively affects the surrounding environment. Therefore, the impact on environment (IoE) becomes a vital concern in selecting the appropriate construction or rehabilitation method for water or sewer pipelines. The research presented in this paper aims at developing an IoE model that compares the open-cut and TT methods. The IoE factors and their related data are collected, analysed and categorised based on literature review and expert opinion. Two models are designed in order to assess the IoE of the open-cut and TT methods. Results of the open-cut technique show that the impact on social factor has the maximum relative weight of 0.36; however, the impact on project characteristics has 0.33 and on environment has 0.30. The impact of TTs on project characteristics has the highest weight of 0.38, in which social factor is the lowest (0.28). The IoE value, using the open-cut method, is 0.4739; however, its value using the TT method is 0.3346. The developed IoE model shows robust results in quantifying the impact on environment of underground utility work. This research is relevant to both industry practitioners and researchers. It develops models to determine the IoE for the open-cut and TT methods. They are also beneficial to the municipal experts. [ABSTRACT FROM AUTHOR]