Demolition

Practices, Technology, and Management

Mark Shaurette, Richard J. Diven

• Publisher: Purdue University Press
• Year: 2011
• ISBN:
  9781612490038
• Topic: Technology & Engineering
• Subtopic: Civil Engineering
• Index: Technology & Engineering

As the built environment ages, demolition has become a rapidly growing industry offering major employment opportunities. During the 1990s the number of contractors grew by nearly 60 percent and there are now over 800 US companies focused on demolition, as well as many more offering this service as part of their portfolio. It has also become an increasingly complex business, requiring a unique combination of project management skills, legal and contractual knowledge, and engineering skills from its practitioners. Created in partnership with the National Demolition Association, Demolition: Practices, Technology, and Management is written specifically with students of construction management and engineering in mind, although it will also be an invaluable reference resource for anyone involved in demolition projects. Since demolition has become such a central part of construction management, this audience includes practicing architects and engineers, general contractors, building and manufacturing facility owners, as well as government officials and regulators. Covered in the book is the full range of technical and management issues encountered by the demolition contractor and those who hire demolition contractors. These include modern demolition practices, the impact of different construction types, demolition regulations, estimating demolition work, demolition contracts, safety on the demolition project, typical demolition equipment, debris handling and recycling, use of explosives, demolition contractors' participation in disaster response, and demolition project management.

CHAPTER 1

INTRODUCTION TO THE INDUSTRY

A. IT’S NOT CONSTRUCTION

This book is designed to be a guide to demolition practice, technology, and management as it is practiced in North America. In 2008 there were approximately eight hundred companies in the United States and Canada whose main activities were classified as demolition. In addition to this group, there are many general contractors and specialty contractors that perform some demolition, usually in conjunction with their non-demolition projects. Even though demolition activities are often grouped into the general classification of construction, it is not construction and, in fact, is much different from most construction activities.

Differences include such tasks as performing the work in a more or less reverse order from construction and the requirement to ensure that hazardous materials have been surveyed and are removed. Tasks associated with removal of hazardous materials are seldom a concern in construction projects. Also, delivery and storage of materials is seldom a concern to the demolition contractor. The cost effect of a potentially large credit for salvage materials from a demolition job can be a significant component of the final net cost and is a determining factor in selecting the method of demolishing a building.

B. WHAT IS DEMOLITION?

In our modern world, demolition has evolved into a rather complex combination of tasks: from clearing sites for new construction to salvaging building materials from structures that have been demolished to removing hazardous materials. Therefore, we ask, “what kind of work does a demolition contractor do?” The following Table 1.1 is a list of typical tasks performed by demolition contractors and a brief explanation of these tasks.

Table 1.01

Demolition Type	Description
Commercial and Industrial Buildings and Structures—Low Rise Demolition	Any building/structure less than eight stories high; usually demolished using heavy equipment such as cranes and excavators equipped with special attachments.
Commercial and Industrial Buildings and Structures—High Rise	Any building over eight stories in height; often demolished using explosives if surrounding conditions and local regulations permit. For non-explosive demolition, floors above eighty feet are usually demolished one floor at a time, and lower floors are demolished with heavy equipment.
High Rise industrial structures such as chimneys, towers, chemical plants, steel mills, and similar structures	This category of demolition includes many special use buildings and structures. They are usually demolished using cranes, excavators, explosives, and various combinations of dismantling techniques.
Sub-grade, Concrete Foundation Demolition	Often the most expensive part of a demolition project is the breaking and removal of heavy, below grade concrete foundations. Large excavators equipped with hydraulic breakers are commonly used to break the concrete. The crane and wrecking ball procedure is also used for breaking foundations. Explosives are used when conditions are suitable.
Utility Demolition	This category can include any type of utilities either above or below grade and is usually a part of the primary demolition task.
Demolition of Parking Lots, Roads, and Runways	These improvements can be either concrete or asphalt and are commonly performed as part of structure demolition, but may also be stand-alone projects.
Bridge Demolition	Bridge demolition has become a major part of the demolition industry as our old bridges become obsolete. This category includes all types of bridges and materials used in their construction.
Railroad Demolition	Includes primarily the removal of abandoned tracks, appurtenant structures, and railroad bridges.
Interior Demolition	This is also a major category for demolition contractors and is typically the first step required for the processes of remodeling or upgrading existing buildings.
Selective Demolition	This term can be applied to most any of the above categories in the sense that “selective demolition” may be defined as removal of specified parts of buildings, structures, utilities, and process equipment. For example, the end wall of a hospital building may need to be removed to permit the construction of an addition to the building.
Explosive Demolition	Explosives used in demolition are typically used to fell buildings and structures or to break up heavy concrete foundations. The term “implosion” is used to describe the process of falling buildings in a controlled manner. A discussion of the use of explosives is included in chapter 11.
Marine Demolition	This category covers demolition of pilings, docks, piers and foundations, sunken vessels, and underwater obstructions.
Disaster Response	This is a broad category and includes cleanup of debris from hurricanes, earthquakes, fires, and floods. Included is the demolition of damaged structures and infrastructure. Also included are emergency rescues.
Historical Salvage	This includes the careful removal and salvage of items of historical importance and is often performed by specialists in this kind of work.
Hazardous Materials Removal	While not a direct demolition activity, the removal of hazardous materials such as asbestos-containing materials (ACM), polychlorinated biphenyls (PCBs), and other hazardous materials are performed as an integral phase of most demolition projects. Either the demolition contractor or a subcontractor will perform this work before demolition work begins. There are a number of regulations and laws governing such work.

C. BRIEF HISTORY OF DEMOLITION

When the ruins of Homer’s ancient Troy were discovered by the German archeologist Heinrich Schliemann, it was determined that Troy was the seventh city to have been constructed on that site. English medieval church building materials often originated in earlier buildings that may have been deliberately demolished to supply materials. Many of these reused materials were recycled from previous structures of Roman origin. Although building stone was the most typically recycled material, timber, tiles, lead, and even plaster or mortar were recycled (Blair and Ramsay 1991). The systematic harvesting of building materials in medieval England was not unique. Hundreds of years earlier, Constantine destroyed city walls and monumental public buildings as punishment during his conquests, only to rebuild with reused building materials to reduce costs (Bowman, Garnsey, and Cameron 2005).

The ravages of time and conquest were not the only reason for demolition. In 1910, the Gillender Building in lower Manhattan, the tallest office structure in the world when constructed in 1897, was razed. This high-class structure just over twelve years old was demolished to make way for a more elaborate and prestigious structure. While the Gillender Building was demolished using over two hundred men over a period of forty-five days with little more than pneumatic tools and power winches, machine wrecking began in earnest in the 1930s when the wrecking ball, as we know it, became common. Early crane wrecking was an adaptation of the ancient demolition practice of ramming. The availability of cranes allowed demolition contractors to suspend heavy lengths of flat or square steel from a crane’s cables and use them as a ram. Ball shaped rams of steel weighing thousands of pounds gradually replaced flat or square iron because these rams could be swung rather than simply dropped (Byles 2005). Cranes equipped with clamshell buckets and compressed air jackhammers soon joined the demolition contractor’s arsenal of machinery to assist in razing structures.

Through much of the early twentieth century, power shovels were employed to load demolition debris when wooden chutes could not be used to convey debris directly into waiting trucks. Advances in the internal combustion engine and later high-output diesel engines allowed machine demolition to rapidly expand. After World War II, the pace of road building and the development of high-strength steel led to significant advancements in earth moving equipment that was well suited to use in the demolition industry. Although the wrecking ball and crane are still used today, advances in hydraulically powered equipment has to a large extent allowed the crane and wrecking ball to be replaced by track mounted excavators. These excavators employ a variety of hydraulically powered attachments to wreck buildings as well as to separate and load demolished materials for reuse, recycling, or landfill disposal.

The use of explosives in demolition is a dramatic process originally used for breaking structures into smaller more easily managed pieces. In the late 1950s, a more controlled use of explosives, often called “implosion,” was first used. The term “implosion” indicat...

Table of contents

• Cover
• Title
• Copyright
• Table of Contents
• Foreword
• Preface
• Acknowledgments
• Chapter 1. Introduction to the Industry
• Chapter 2. The Demolition Contractor
• Chapter 3. Modern Demolition Practices
• Chapter 4. Types of Demolition—Building and Structures
• Chapter 5. Demolition Regulatory Guides
• Chapter 6. Estimating—Quantifying and Pricing the Demolition Project
• Chapter 7. Contracts and Accounting for the Demolition Project
• Chapter 8. Safety on a Demolition Project
• Chapter 9. Demolition Equipment
• Chapter 10. Material Handling and Recycling
• Chapter 11. Explosives in Demolition
• Chapter 12. Disaster Response
• Chapter 13. Project Management
• Glossary of Terms, Abbreviations, and Acronyms
• Index