7.0 ROAD MATERIALS - TERMS AND STANDARD SPECIFICATIONS

Question 1

Aggregates to be classified as good quality, must undergo various test enumerated as follows:

Answer 1

 Test for strength
 Test for soundness
 Test for affinity and swell
 Test for shape and texture
 Test for resistance to polishing
 Degradation Test

Question 2

What is the criterion for aggregate strength test

Answer 2

Los Angeles Abrasion Test
(AASHTO T 96)

Question 3

It refers to the resistance of materials to deterioration from the effect of action like freezing and thawing. The common test for soundness is the application with sodium or magnesium sulfate. (AASHTO T 104)

Answer 3

Soundess

Question 4

It is considered unsound when volume changes in the aggregate are induced by weather, such as alternate cycles of wetting and drying or freezing and thawing.

Answer 4

Aggregate

Question 5

What is the characteristic of a strong durable pavement?

Answer 5

It must have binder that adhere or stick firmly to the aggregate particles.

Question 6

It is the term used when the aggregate has a greater affinity for water than asphalt.

Answer 6

Hydrophilic

Question 7

What does it mean when the aggregate is considered Hydropholic

Answer 7

The chemical bond between the aggregates and water is much stronger than those between aggregates and asphalt.

Question 8

What needs to be considered as good asphalt or concrete road

Answer 8

the rubber tire is in direct contact with the aggregate and not with the binde

Question 9

It is a test for aggregates that degrade in the presence of water. This is measured through mechanical agitation in water under test designation T-210 of AASHTO.

Answer 9

Degration Test

Question 10

is a viscous liquid used as a binder for aggregates in road construction. At normal temperature, asphalt is either slightly thicker than water or a hard, brittle material that breaks under a hammer blow when cold.

Answer 10

Bituminous Materials or Asphalt

Question 11

It is a petroleum product consisting of asphalt cement mixed with a liquid distillate, such as diesel, kerosene, or gasoline. The less viscous form of it contains as little as 15% of the diluent. The use of this is discouraged for two main reasons: (1) it can be used as a fuel; and (2) it is considered an air pollutant.

Answer 11

Cutback Asphalt or Liquid Asphalt

Question 12

There are three classifications of cutback asphalt:

Answer 12

Slow Curing (SC)
Medium Curing (MC)
Rapid Curing (RC)

Question 13

It is a type of mixture wherein minute globules of asphalt disperse in water. The asphalt content ranges from 55% to 70% by weight. Emulsion can be applied or mixed at normal temperature, as when the water content evaporates, the asphalt remains.

Answer 13

Asphalt emulsion

Question 14

It is suitable only for roofing and similar applications. Its use in highways is limited to waterproofing of structures and filling joints in concrete pavement.

Answer 14

Oxidized asphalt

Question 15

It is a by-product of the distillation process of coal. Tars are produced from gashouse coal tar, cook oven tars and water gas tar.

Answer 15

Road tar

Question 16

is a layer of asphalt bound aggregate laid to an existing pavement. The purpose is to level out distorted surface or to cover cracks and joints of the pavement.

Answer 16

Asphalt overlay

Question 17

It is defined as the lowest moisture at which the soil will flow upon the application of a very small shearing force.

Answer 17

Liquid Limit

Question 18

It is defined as the minimum moisture content at which the soil can be readily molded without breaking or crumbling.

Answer 18

Plastic Limit

Question 19

It indicates compressibility. A high PI means a high degree of compressibility of a soil. It is also related to permeability: the higher the PI, the lower the permeability, and vice versa.

Answer 19

Plasticity Index

Question 20

It determines the bearing capacity of soil under its worst condition.

Answer 20

California Bearing Ratio (CBR)

Question 21

It determines the grain size distribution in soils by sieve, hydrometer, or a combined analysis. It is widely used in the classification and identification of soil and is an important criterion in the classification of highway subgrade materials.

Answer 21

Sieve Analysis

Question 22

It evaluates the structural strength of coarse aggregate. It provides an indication of quality based on resistance to impact and wear.

Answer 22

Abrasion Test