Read interviews with Steve Kay and Dave Shepherd, two of Bechtel's leading tunnelling experts.
We are entering a new era of industrial development where a rethinking of infrastructure, as it relates to achieving the SDGs, is critical.
The paper discusses the primary drivers for technological change in railways and examines a new means for integrating complex systems in rail projects whilst meeting customer expectations and securing optimum stakeholder engagement throughout the project life-cycle.
This paper reviews integral methods to numerically solve the Bernoulli equation in compressible flow for several common situations: orifices, relief valves, and control valves.
This paper provides structural engineers with the basic tools for the understanding, calculation and use of foundation impedance functions.
This technical paper details a multi-phase subsurface investigation (SI) program performed to provide geo-characterization of a brownfield site for the modernization of a large industrial facility.
This paper includes a general description of the site and its geologic conditions, along with subsurface and groundwater conditions in the vicinity of the pile load test area
This paper introduces the relevance of Non Technical Skills in railway industry training schemes for the purpose of improving business performance and safety standards.
This paper provides an overview for the selection of the materials of construction for Liquefied Natural Gas liquefaction plants. The selection of optimum materials of construction affects both the initial capital investment and operational costs and profits.
The new Panama Canal locks are being built to accommodate ships with a total fresh water draft of 50 feet (15 meters), a beam of 160 feet (49 meters) and a length of 1,200 feet (366 meters). This compares with the current canal limits of about 41 feet (12 meters) of draft, 110 feet (30 meters) of beam and 1,000 feet (305 meters) in length.
Integration of the two OEMs’ advanced gas turbine designs could deliver combined cycle efficiencies that leapfrog the best available today.
This paper presents an improved two-step method that characterizes the incoherent FIM using combination of spatial mode shapes. Results are compared with SASSI2010 to judge the method’s accuracy for various response quantities, and sensitivity of results to the number of spatial modes is studied. The results show that the proposed method is quite accurate when a few basemat mode shapes are included in addition to the six rigid body mode shapes.
This paper discusses the importance of careful planning for proposed expansion of major railway systems.
The Crossrail project is the biggest construction project in Europe. The scope consists of 13 miles (21 kilometers) of twin bore tunnels and seven new stations. An unusual and critical challenge of the job was to modernize the Connaught Tunnel, a Victorian tunnel built for Victorian rail use, to meet the space needs for the new electrified trains.
In design of pressure relief systems, a pool fire is one of the most typical relief cases. This paper illustrates one method where the heat input is limited by the fuel supply.
Ships have significantly increased in size and number over the last decades. Ports and waterways are accommodating these ships and at the same time new terminals are designed in the existing infrastructure. In restricted water moored vessels can be affected by hydrodynamic forces induced by passing ships. The ROPES project was initiated to investigate these effects, to develop a numerical model for predicting these loads and to validate this model. This paper provides an overview of the ROPES project and its results.
This technical paper describes different design configurations of tanks where overfilling is a possibility.
At Crossrail, we are passionate, not just about building a new railway but ensuring it is delivered in a way that provides a lasting economic, environmental and social sustainability legacy. We have enshrined this in our strategy and governance processes and our contractors have joined us on this journey. This paper provides a comprehensive yet concise account of how Crossrail has organized itself to deliver a sustainable outcome as well as detailing a structure for successful outcomes.
This paper presents a three-step method for designing steel plate composite (SC) walls subjected to missile impact.
Natural gas pipelines commonly transport small amounts of sulfur as hydrogen sulfide and mercaptans of various types. This paper presents test results for a new process for removing elemental sulfur.
This technical brief draws upon the second-law based exergy concept to rigorously quantify the performance entitlement of a supercritical high-pressure boiler section in a heat recovery steam generator utilizing the exhaust of a gas turbine to generate steam for power generation in a steam turbine.
Net thermal efficiency ratings of 60% are here —what’s next?
Pulse detonation combustion holds the key to 45% simple cycle and close to 65% combined cycle efficiencies at today’s 1400-1500°C gas turbine firing temperatures.
Assuring the protection of people and the environment from unnecessary exposure to radiation is of great concern to nuclear electric power generators and regulators. In order to secure and maintain a license for operation of a nuclear power plant in the United States, the applicant is required to assess postulated scenarios to determine if an accidental chemical release either onsite or offsite will result in a design-basis event. When determining design-basis events, accident categories such as fire, explosion and/or toxic vapor cloud formation are considered.
The purpose of this paper is to assess the differences in foundation bearing pressure demand obtained using the Random Vibration Theory (RVT) method and the time history method.
This paper provides an alternative design approach for thermal effects. Unlike the conventional approaches used in ACI 349 and ACI 359, where the main emphasis was given for estimating thermal loads and combining them with mechanical loads, the proposed design approach calculates thermal loads on the basis of design strengths.
This study provides recommendations for the S- and P-wave velocity, site attenuation, and unit weight of the reference rock for Central and Eastern North America. The reference rock condition defines the boundary between the site specific amplification and the regional ground motion model. A consistent definition of this boundary across models allows for models of site amplification and ground motion to be developed independently.
In this paper is a detailed analysis of the effect of water temperature on the overall efficiency of a fogging system, both from an experimental and a theoretical view point.
Michael Graham speaks about the largest and most complex DOE project; the Waste Treatment Plant in Hanford, Washington. This one-of-a-kind project includes a complex of facilities being designed and built to immobilize the highly radioactive waste stored in 177 aging underground tanks. Some of the tanks date back to World War II and 67 have been reported to have leaked. WTP will immobilize the waste using a process known as vitrification, which mixes the solid and liquid waste with molten glass to safely isolate the waste from the environment.
An enhanced screening algorithm for power generation system total ownership cost (capital and operating) and thermal performance (output and efficiency) simplifies the analysis.
LNG liquefaction plants can benefit significantly by power augmentation of gas turbines. Gas turbine inlet cooling solutions, such as evaporative and mechanical cooling systems, have been operating for several years and are currently being implemented in 11 large LNG trains utilizing the ConocoPhillips Optimized Cascade® LNG process.
This investigation identified that water consumption practices in camps were not fully understood and no consistent standards were being employed, contributing to errors in sizing water supply systems in camps. This paper details the water conservation evaluation alternatives and cost/benefit analysis based on current and predicted water usage for Mining & Metals projects.
The Bechtel National Inc. team designing, building, and commissioning the Hanford Waste Treatment Plant (WTP) reported several major accomplishments in 2013.
The manuscript provides a workshop summary that can be seen as the framework for a “state-of-practice” document. The purpose(s) of break analysis, methods used, and documentation of important assumptions are addressed. Commentary citing concerns raised during and after the workshop are also included as it was clear that our ability to conduct accurate and realistic dam break analyses is limited.
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.
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.
This paper addresses and evaluates the performance of several turbulence model options and modifications within a CFD code for the assessment of intake flow.
A method to decrease the modeling time for a computational fluid dynamics (CFD) simulation of the pump-out process of a multi-constituent, radioactive slurry in a mixing vessel is developed.
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.
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.
This paper discusses criteria for evaluating the most efficient combination of a centrifugal compressor and its gas turbine driver as an integral package from a purchaser’s viewpoint. It also addresses API standard requirements on gas turbine driven centrifugal compressors.
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.
GE’s new FlexEfficiency combined cycle technology aims to couple unprecedented operational flexibility with extremely high efficiency.
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.
A new formula addresses blind spots by estimating the value of the part-load performance of cycling combined-cycle plants.
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.
This paper presents a detailed and practical finite element model used to perform a comprehensive stress analysis of an anchorage zone of a large post-tensioned containment. Both local and general anchorage zones are evaluated.
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.
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.
This study illustrates how, in cases of scarce water supplies with high sediment loads, there can be tradeoffs between the differing needs for managing water and sediment.
This paper provides details of an improved adsorbent bed support design that utilizes a superior sealing mechanism that features a fixed hold down ring design. The fixed hold down ring design provides an innovative method of sealing the expansion gap that will effectively eliminate the pathway by which molecular sieve granules and fines enter the expansion gap.