Civil Engineer Expert

Project Management in Construction, 5th Edition

For more than thirty years, Construction Project Management by Clough and Sears has been considered the preeminent guide to the Critical Path Method (CPM) of project scheduling. It combines a solid foundation in the principles and fundamentals of CPM with particular emphasis on project planning, demonstrated through an example project.

This Fifth Edition features a range of improvements. New pedagogical devices improve absorption of the material. Updated labor, material, and equipment pricing is incorporated into the text. Coverage is enhanced by discussions of contemporary planning and management methods such as Work Breakdown Structures (WBS) and the Earned Value Management System (EVMS).

A highway bridge with a complete cost estimate, including SI units, illustrates each of the principles of project management. Using this basic information and the case studies in the appendix, readers are given project management problems and hands-on project management experience.

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Oldcastle Materials Inc. considers rebuilding larger wheel loaders when they reach the end of their first life.

Extreme maintenance practices can help you extend equipment life spans — but be aware you are managing risk.

In today’s economy, we’re all trying to stretch things as far possible. Whether it’s stretching time between oil changes in your car or holding off on buying that new pair of work boots you know you need, we’re pushing the limits.

The construction industry is no exception. Its economic downturn has prompted many contractors to run equipment for more hours than normal. Capital for new machines is scarce so equipment is being kept longer and worked harder. Knowing that the equipment has to last, managers carefully watch oil samples for wear particle signals that mean component failure is approaching. And some equipment managers are even replacing small components, such as water pumps and alternators, before they fail.

“We’re probably adding 20 percent more to the life of our equipment than we would in normal economic times,” says Rex Davis, a vice president at RMCI Inc., Albuquerque, N.M. “Sooner or later we have to make some decisions (about trading in equipment). It doesn’t do any good to have new equipment if you don’t have work for it. Hopefully the economic tide will turn soon.”

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Twinkle Kisogawa bridge

An extradosed bridge employs a structure that is frequently described as a cross between a girder bridge and a cable-stayed bridge. The name comes from the French word extradossé, which is derived from the word extrados. Extrados is defined as the exterior curve of an arch.

This description is somewhat deceptive, since many cable-stayed bridges have some sort of box-girder deck. The difference is one of degrees.

A typical cable-stay bridge has a tower with a height above the deck at least half the span to the next support, since the cables are the vertical support and must come at a relatively high angle.

In an extradosed bridge, the deck is directly supported by resting on part of the tower, so that in close proximity to the tower the deck can act as a continuous beam. The cables from a lower tower intersect with the deck only further out, and at a lower angle, so that their tension acts more to compress the bridge deck horizontally than to support it vertically. Thus the cable stays act as prestressing cables for a concrete deck, whether made with I-beam girders or a box girder. The deck of an extradosed bridge can be thinner than that of a comparable span-beam bridge, but must be thicker than that of a conventional cable-stayed bridge of comparable span.
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Why Did Cowboys Facility Collapse?

A fabric-covered, steel frame practice facility owned by the National Football League’s Dallas Cowboys collapsed under wind loads significantly less than those required under applicable design standards, according to a report released on October 6 for public comment by the Commerce Department’s National Institute of Standards and Technology (NIST).

Located in Irving, Texas, the facility collapsed on May 2, 2009, during a severe thunderstorm. Twelve people were injured, one seriously.

Based on the national standards for determining loads and for designing structural steel buildings, NIST researchers studying the Cowboys facility found that the May 2 wind load demands on the building’s framework—a series of identical, rib-like steel frames supporting a tensioned fabric covering—were greater than the capacity of the frame to resist those loads.

Assumptions and approaches used in the design of the Cowboys facility led to the differences between the values originally calculated for the wind load demand and structural frame capacity compared to those derived by the NIST researchers. For instance, the NIST researchers included internal wind pressure due to the presence of vents and multiple doors in their wind load calculations because they classified the building as “partially enclosed” rather than “fully enclosed” as stated in the design documents. The NIST researchers also determined that the building’s fabric could not be relied upon to provide lateral bracing (additional perpendicular support) to the frames in contrast to what was stated in the design documents and that the expected wind resistance of the structure did not account for bending effects in some members of the frame.

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Shell structure is able to adapt to changing environmental conditions.

Weather conditions such as wind and snow loads can cause failure and collapse of supporting structures in roofs and similar constructions. Based on new hybrid intelligent construction elements (HICE), researchers at the University of Stuttgart have developed a shell structure which is able to adapt to changing environmental conditions. In a further step, the scientists will now use their knowledge to develop machines from these new structural elements which will also be able to react to their environments and adapt to given conditions.

According to experts, this development may eventually lead to a significant acceleration of entire construction processes in mechanical, electrical and control engineering.

A research group of six engineers from different fields such as civil, aerospace, mechanical and process engineering is funded by the Deutsche Forschungsgemeinschaft (German Research Foundation) with a grant of 1.858 m € assigned for the first three years of a six-year project. The research group has started to operate in June.

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New Way To Monitor Faults May Help Predict Earthquakes

Scientists at the Carnegie Institution have found a way to monitor the strength of geologic faults deep in the Earth. This finding could prove to be a boon for earthquake prediction by pinpointing those faults that are likely to fail and produce earthquakes. Until now, scientists had no method for detecting changes in fault strength, which is not measureable at the Earth’s surface.

Paul Silver* and Taka’aki Taira of the Carnegie Institution’s Department of Terrestrial Magnetism, with Fenglin Niu of Rice University and Robert Nadeau of the University of California, Berkeley, used highly sensitive seismometers to detect subtle changes in earthquake waves that travel through the San Andreas Fault zone near Parkfield, California, over a period of 20 years. The changes in the waves indicate weakening of the fault and correspond to periods of increased rates of small earthquakes along the fault.

“Fault strength is a fundamental property of seismic zones,” says Taira, now at the University of California, Berkeley. “Earthquakes are caused when a fault fails, either because of the build-up of stress or because of a weakening of the fault. Changes in fault strength are much harder to measure than changes in stress, especially for faults deep in the crust. Our result opens up exciting possibilities for monitoring seismic risk and understanding the causes of earthquakes.”

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What Is Civil Engineering All About?

A Career In Civil Engineering

Civil engineering deals with a variety of construction and maintenance tasks, like building and maintaining roads, bridges, tunnels, buildings, airports, dams, water works, sewage systems and ports. A civil engineer not only requires a high standard of engineering knowledge, but also supervisory and administrative skills. The work involves planning, constructing and maintaining.

The planning and designing part demands site investigation, resource feasibility study and on-the-spot decision making. An engineer has to be quick to make a decision because emergencies do come up and need to be dealt with then and there. Other important duties of an engineer involve taking care of work within the local government guidelines and getting permission for plans, creating a cost estimate and construction schedules and post-completion maintenance of the project.

There are many specialized branches of civil engineering such as dealing with structures, water resources, environment, construction, transportation and geo-technical engineering. For most projects, civil engineers work in teams or sometimes even in coordination with other engineers.

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