Did you know that?

This post has been compiled in parallel with the dictionary you can find in the previous post. While going over this post, I would advise you to visit the Glossary/dictionary as well. This post is the result of several construction materials that are referenced in the bottom of this page. Interesting facts and lists are compiled in the aim of increasing awareness and knowledge in the field of construction/ construction equipment, and hopefully help decision making processes become more accurate and efficient.

This list is preliminary and will be subject to continuous improvements, elaborations, lists and facts. And please, again, do not hesitate to comment and suggest topics for discussions.

Did you know that?

>In the construction process, the three major inputs are construction equipment, labor and materials.

>Combustion engines have its performance reduced as the altitude starts increasing above a certain level, that is due to the decrease of the air density. Turbocharged engines cope better with altitude than naturally aspirated combustion engines.

>Studies have shown that construction companies face a high rate of bankruptcy. According to studies led by Dun & Bradstreet and others, the major reasons behind the failures of the construction companies are:

  1. Lack of capital
  2. Poor cost estimating
  3. Inadequate cost accounting
  4. Lack of general management ability
  5. Absence of contingency plans
  6. Poor understanding of the nature of the site/location (soil characteristics); can lead to greater excavation costs and time and dumping costs

>The most uncertain costs among the owning and operating costs of industrial and construction equipment are the maintenance and repair costs (M&R). The 4 parameters that affect most the M&R costs are (by decreasing level of impact):

  1. Fuel Volume consumed
  2. Age of the machine
  3. Manufacturer of the equipment
  4. Preventive maintenance costs

>Several factors come together when selecting a construction equipment for a specific project. All these factors serve the sole purpose of maximizing the return on the investment of buying the equipment. In other words, maximizing the profit for the project. Some of the most relevant criteria when selecting a machine are:

  1. Cost per unit of production
  2. Fuel Consumption
  3. Future use of the equipment
  4. Availability
  5. Availability of parts and service
  6. Reliable record of the brand and the product line
  7. Effect of equipment down-time on the project’s operations
  8. Financial facilities offered by the dealer/company and possibility of buy-back after the end of the construction project
  9. User-friendliness of the equipment against the operator’s capabilities and skillfulness
  10. Soil characteristic, trafficability and loadability
  11. Location and site layout

>Compaction is the process during which soil density is increased by allowing void to escape from soil particles. Many factors come together to achieve a successful compaction operation:

  1. Appropriate compaction equipment; may vary from tamping foot rollers, grid or mesh rollers to vibratory compactors
  2. Soil moisture content
  3. Lift thickness
  4. Number of passes
  5. Ground contact pressure
  6. Compactor weight
  7. Compactor speed
  8. Vibration frequency and amplitude

>Concrete is produced by mixing portland concrete, aggregates such as limestone or granite and water. Some chemical or mineral additives can be used to improve workability and extract specific properties of the concrete.

Concrete mixing commonly occurs in batching and mixing plants or truck mixers. In the plants, a complete mixer cycle lasts 2 to 3 minutes. During mixing process, 10% of the water’s total amount should be added first, then 80% of the water during charging of ingredients, and the last 10% at the end. All ingredients should be present before one fourth of the mixing time. This would allow an efficient mixing process and help cleaning afterwards.

Truck mixing process requires a minimum of 70 to 100 revolutions and material should be discharged after 1.5 hours or 300 revolutions since the start of the mixing. Important factors that affect the maximum safe hauling distance of concrete mix are:

  1. Temperature
  2. Road condition
  3. Truck body type
  4. Mix design

References

  1. Fan, H and Jin, Z. (2011). A Study On The Factors Affecting The Economy Life Of Heavy Construction Equipment. Department of Building and Real Estate, The Hong Kong Polytechnic University. 27 (1), p923-928.
  2. Featured picture courtesy of
  3. Nunnally, S (2007). Construction methods and management. 7th ed. Ohio: Pearson Prentice Hall.
  4. Nunnally, S (2010). Construction methods and management. 8th ed. Upper Saddle River, N.J: Prentice Hall.
  5. Peurifoy, R, Ledbetter, W and Schexnayder, C (1996). Construction planning, equipment, and methods. 5th ed. New York: The McGraw-Hill Companies, Inc.
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