CINDERS

• Cinder is a pyroclastic materials i.e. igneous rocks formed from volcanic eruptions.

• Cinders are similar to pumice.

• A more modern name for cinder is Scoria.

Geologic characteristics:

• Uncemented.• Vitric.• Having bubble-like cavities, called vesicles.• specific gravity between 1.0 and 2.0• Typical cinders are red or black in color.• Contain numerous gas bubbles "frozen" into

place as magma exploded into the air and then cooled quickly.

USAGE OF CINDERS:

• On track surfaces and roads to provide additional traction in winter conditions.

• As inorganic material in xeriscaping.• In construction replaced by aggregates

(coarse).• In making of cinder blocks.

ADVANTAGES:

• Lesser dead load on structure.

DISADVANTAGES:• Lower strength cannot replace aggregates

completely in concrete.

IS code recommendation for usage of cinders :

IS 2686 -1977

WHY CINDERS AT SITE ?

• Excellent filler material .• Cost savings .• Accommodation for various traps (drainage).

SEISMIC JOINTS

A seismic joint is a system that can handle most seismic events.

The unique features are:• Can handle the rapid acceleration related to a

seismic event.• It is multi-directional (i.e. can accommodate vertical

movement or lateral shear). • Seismic joints have a range of +/- 50% for a total of

100% movement. • It should return to normal after the seismic event.

SEISMICITY IN INDIA

As per IS 1893:2002 (Part 1), India has been divided

into 4 seismic zones.• Zone II Low seismic hazard• Zone III Moderate seismic hazard • Zone IV High seismic hazard • Zone V Very high seismic hazard

FEATURES OF A SEISMIC JOINT

• Water tight.• Traffic durable.• Sound dampened.

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