Unit – 4

Instrumentation in Civil Engineering Structures

4.1           Various Instruments used in construction, water resources, Environmental Engineering

Various Instruments used in construction

Construction equipment can be categorized in to 4 main sections based on purpose and use, They are:

1. Earth Moving equipment
2. Construction vehicle
3. Material Handling Equipment
4. Construction Equipment

1. EARTH MOVING EQUIPMENT

• Excavators
  Graders
  Loaders
  Skid loader
  Crawler loaders
  Backhoe
  Bulldozers
  Trenchers
  Scrapers
  Wheeled loading shovels

2. CONSTRUCTION VEHICLE

• Tippers
• Dumbers
• Trailers
• Tankers

3. MATERIAL HANDLING EQUIPMENT

Crane
Conveyors
Hoists
Fork Lifts

4.CONSTRUCTION EQUIPMENT

Concrete Mixture

Compactors

Pavers

Road Rollers

5. TUNNELING EQUIPMENT

Road Headers
Tunnel Boring Machines (TBM)

6. OTHER CONSTRUCTION EQUIPMENT

Water resources

Water resources are sources of water that are useful or potentially useful to humans.

• It is important because it is needed for life to exist.
• Many uses of water include agricultural, industrial, household, recreational and environmental activities.
• Virtually all of these human uses require fresh water.
• Only 2.5% of water on the Earth is fresh water, and over two thirds of this is frozen in glaciers and polar ice caps.
• Water demand already exceeds supply in many parts of the world, and many more areas are expected to experience this imbalance in the near future.
• It is estimated that 70% of world-wide water use is for irrigation in agriculture.
• Climate change will have significant impacts on water resources around the world because of the close connections between the climate and hydrologic cycle.
• Due to the expanding human population competition for water is growing such that many of the worlds major aquifers are becoming depleted.
• Many pollutants threaten water supplies, but the most widespread, especially in underdeveloped countries, is the discharge of raw sewage into natural waters.

4.2           Foundation Engineering, Thermocouples, Condition    monitoring equipments, Half Cell Potentiometers, Strain Gauges

Foundation Engineering

In engineering, a foundation is the element of a structure which connects it to the ground, and transfers loads from the structure to the ground. Foundations are generally considered either shallow or deep. Foundation engineering is the application of soil mechanics and rock mechanics (Geotechnical engineering) in the design of foundation elements of structures.

Thermocouples

The thermocouple can be defined as a kind of temperature sensor that is used to measure the temperature at one specific point in the form of the EMF or an electric current. This sensor comprises two dissimilar metal wires that are connected together at one junction. The temperature can be measured at this junction, and the change in temperature of the metal wire stimulates the voltages.

Half Cell Potentiometers

Half – Cell Electrical Potential Method to Measure Corrosion of Reinforcement in Concrete .The half-cell potential (HCP) test assesses the condition of the steel embedded in concrete with regard to corrosion activity. In this method, the electrical potential difference between the upper steel re-bars and a standard portable reference electrode in contact with the concrete surface is measured. The half cell is usually Copper/ Copper Sulphate or Silver/ Silver Chloride cell but other combinations are used. The concrete functions as an electrolyte and the risk of corrosion of reinforcement in immediate region of the test location may be related empirically to the measured potential difference. The typical layout of the equipment is shown Fig. 2.1.It consist a rigid tube composed of dielectric material that is non-reactive with copper or copper sulphate, a porous wooden or plastic plug that remains wet by capillary action, and a copper rod that is immersed within the tube in a saturated solution of copper sulphate. The solution is prepared using reagent grade copper sulphate dissolved to saturation in distilled or deionized water. An electrical junction device is used to provide a low electrical resistance liquid bridge between the surface and the half cell is normally a sponge. Electrical contact solution is made from normal house hold detergent

Strain Gauges

Our strain gauge type civil engineering transducers use strain gauges as detecting sensors. These transducers measure concrete strain, soil pressure, water pressure, stress, displacement, inclination, and other various physical quantities and convert them electrically. They are designed to deliver the best performance for many different applications and to maintain superb sensitivity, accuracy and durability over a long period of time. If they are used in combination with data loggers supplied by our company, it is possible to build an automated multi-point measurement system that operates unattended to gather data for a long time. Our civil engineering transducers are now the indispensable components used to conduct experiments on or pursue research for general buildings, bridges, ground, tunnels, dams and other civil engineering structures. They also play an important role in predicting disasters, developing new construction techniques, and preparing safety designs for such mass-transport means as railways, vehicles, ships and airplanes.

4.3           Management of Utilities using telemetry & SCADA System

1. The term supervisory control and data acquisition systems – also known as SCADA – is quite a mouthful. In reality SCADA is a well-established, if not complex, means for monitoring utilities (among other production and critical infrastructure applications) remotely. SCADA systems collect the data and automate it across the utility’s applications.
2. By definition, SCADA systems are industrial control systems (ICS). They fall into the operations technology (OT) classification, which describes the hardware, software, and communication technology used in creating, storing, exchanging, and using information.
3. No matter what they are monitoring, however, SCADA systems are essentially built the same. They pull together hardware, software, and connectivity and then organize it into four layers: field instrumentation; programmable logic controllers (PLCs) and remote telemetry units (RTUs); communications; and the SCADA host platform.
4. While typical applications for SCADA systems include manufacturing plants, oil & gas refineries, power plants, and water and wastewater treatment plants and remote utilities monitoring, this blog will focus exclusively on water/wastewater, energy and other utilities monitoring.

4.4           Role of Engineers in Sustainable Development

• Engineers have a central role in sustainable development
• Developing sustainable technology . Technology is an essential part of society but it is not the only thing . Engineers should take on a more active role in society
• Sharing own expertise
• Collaborating with others

4.5           Concept of green buildings and LEED Certification

A ‘green’ building is a building that, in its design, construction or operation, reduces or eliminates negative impacts, and can create positive impacts, on our climate and natural environment. Green buildings preserve precious natural resources and improve our quality of life.

There are a number of features which can make a building ‘green’. These include: 

• Efficient use of energy, water and other resources
• Use of renewable energy, such as solar energy
• Pollution and waste reduction measures, and the enabling of re-use and recycling
• Good indoor environmental air quality
• Use of materials that are non-toxic, ethical and sustainable
• Consideration of the environment in design, construction and operation
• Consideration of the quality of life of occupants in design, construction and operation
• A design that enables adaptation to a changing environment

Any building can be a green building, whether it’s a home, an office, a school, a hospital, a community centre, or any other type of structure, provided it includes features listed above.

However, it is worth noting that not all green buildings are – and need to be - the same. Different countries and regions have a variety of characteristics such as distinctive climatic conditions, unique cultures and traditions, diverse building types and ages, or wide-ranging environmental, economic and social priorities – all of which shape their approach to green building.

LEED Certification

LEED (Leadership in Energy and Environmental Design) is the most widely used green building rating system in the world. Available for virtually all building types, LEED provides a framework for healthy, highly efficient, and cost-saving green buildings. LEED certification is a globally recognized symbol of sustainability achievement and leadership

Reference Books

1. A Text Book of Building Materials, by C.J. Kulkarrni
2. Building Materials, by P. C. Varghese
3. Building Construction, by P. C. Varghese