Design of radial reinforcement for prestressed concrete containments

27 February 2013

This paper discusses the issue of radial tension in prestressed cylindrical and dome shaped structures and proposes formulae to calculate radial stresses. A practical example is presented to illustrate the use of the proposed method which is then verified by using state-of-the-art finite element analysis. This paper also provides some practical design consideration for detailing of radial reinforcement in prestressed containments.

A new modular paradigm in building information modeling

01 December 2012

As powerful as Building Information Modeling (BIM) tools are in modeling the built environment, current BIM strategies limit the size of facilities that can be modeled while increasing the time needed for modeling and the quality of BIM models produced. In the same way that prefabricated modular construction techniques are improving the speed and quality of construction delivery, a modular approach to BIM modeling substantially increases the scale of facilities that can be modeled while decreasing modeling time and increasing model quality.

A comparison of in-situ and laboratory shear wave velocity measurements in compacted backfill

27 June 2012

This paper compares the results of estimated values made during the licensing and design phases of the project, based primarily on laboratory test results, with in-situ shear wave velocity measurements made during the actual construction. In particular, SASW results from the first two levels of backfill tested (about 25 and 50 ft [7.6 to 15.2 meters] of backfill placed) are evaluated. 

Evaporative cooling of gas turbine engines

27 June 2012

This paper provides a detailed treatment of media evaporative cooling, discussing aspects that would be of value to an end user including selection of climatic design points, constructional features of evaporative coolers, thermodynamic aspects of its effect on gas turbines and approaches to improve reliability. 

Pioneering a new model for national infrastructure in Gabon

27 March 2012

Bechtel and the government of Gabon developed and are delivering a groundbreaking $25 billion National Infrastructure Master Plan (NIMP) that will enable the country to modernize the national workforce, expand access to social development, and advance connectivity within the country, across Africa, and with the rest of the world.

A Proposed Definition of CHP Efficiency

08 June 2010

Many alternative approaches for determining a useful definition of combined heat and power fossil power plant efficiency have been proposed, although most fail to produce a universal definition. This article shows how an exergy analysis supplies the elusive solution.

Multi-user offshore hub concept

The Multi-User Offshore Hub (MUOH) is an innovative idea for constructing and operating new major port facilities for the export of dry bulk (ore, coal), liquid bulk (oil and gas), or handling containers.

Africa LNG: The new Middle East

Major new discoveries of natural gas in many parts of Africa are leading to the development of a greatly expanded industry—leading some to call Africa the new Middle East of hydrocarbon development. The recent discoveries in Mozambique and Tanzania are particularly significant. At the same time, LNG processing and transport costs have rapidly declined, making it possible to sell the fuel at attractive prices to customers in Europe, Asia, and the Americas. This paper examines the state of LNG development in Africa.

Intermodal port operations in Gabon

Unlike many of the ports in West Africa, Port Gentil has deep water close to shore and it is relatively sheltered from ocean swells, behind Cape Lopez. Its main disadvantage is having no land links to the rest of the country, which isolates it and makes access difficult. At present, it is used mostly to export limited amounts of crude oil.