The detailed method of highway construction

By making extensive surveys and subgrade groundwork, highway construction is normally conducted. The methods and technology for constructing highways are upgraded in due course of time and turns to be more advanced.

The improvement in technology has increased the grade of skill sets essential for dealing with highway construction projects.

This skill differs from project to project, on the basis of different factors like the project’s complications and type, the contrasts among new construction and reconstruction, and variations among urban region and rural region projects.

There exist various components of highway construction which are segregated into technical and commercial components of the system. Given below, some illustrations of them:

Technical Components -

a. Materials
b. Material quality
c. Installation systems
d. Traffic

Commercial Components -

a. Contract understanding
b. Ecological characteristics
c. Political characteristics
d. Legal characteristics
e. Public interests

Generally, construction starts at the lowermost elevation of the site, in spite of the project type, and moves upward. After evaluation of the geotechnical specifications of the project, the following information is provided:

Present ground conditions -

a. Necessary apparatus for excavation, grading, and material transportation to and from the site
b. Characteristics of materials to be excavated
c. Necessity of dewatering for below-grade work
d. Necessity of shoring for excavation protection
e. The quantities of water for compaction and dust control



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Published By
Rajib Dey
www.constructioncost.co
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Vital factors to impact the design and construction of embankment dams

Numerous factors provide significant effect on the construction and design of embankment dam. Through the design phase, the designer should consider these factors to make the design better.

Given below, the detail information on these factors :-

a. Accessibility of materials for construction
b. Properties of embankment dam site
c. Shape and size of valley where the dam is developed
d. Atmosphere of the area
e. Diversion of river
f. Existing time for construction
g. Function of the reservoir
h. Feasible wave action
i. Earthquake activity in the area

Accessibility of Materials for Dam Construction: Generally, construction materials for embankment dams can be easily accessed and frequently available at or close to construction site at low cost. It will significantly impact the design of embankment dam.

If excavated material like earth excavated for spillway construction is utilized in the construction, the economy of construction is enhanced.

Embankment dam designed and constructed on the basis of existing construction material.

Type of material obtainable at project site Designed embankment dam on the basis of existing construction material.

a. Impervious soil material Consistent embankment dam
b. Rock and impenetrable material Rock fill dam
c. Previous and Impervious material Zoned earth dam,

Properties of Embankment Dam Site: Normally, embankment dams are built up on nearly all types of soil. The design is significantly impacted by the characteristics of soil upon which the dam is built up. One of the significant impact is managing the type of treatment applied for the foundation.

Besides, soil properties affect the dimension of the dam as for example if the soil contains low bearing strength, then it is essential to trim down slopes and employ superior cross section and freeboard.

These measures are essential to deal with deferential settlement of the embankment dam.

For more information, visit the following site aitech.ac.jp

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Published By
Rajib Dey
www.constructioncost.co
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Various types of tests conducted to verify the quality of aggregates in road work

Aggregate is a vital element in pavement construction. The load transfer capacity of pavements is significantly impacted by the aggregated. So, it is recommended to examine the aggregates comprehensively prior to utilize them in the construction site.

The aggregates should contain the properties like durable and long-lasting with perfect shape and size so that the pavement can function monolithically. Aggregates are evaluated for strength, toughness, solidity, shape, and water absorption.

In order to decide the suitability of the aggregate for use in pavement construction, The following tests are conducted to check whether the aggregates are suitable to be utilized in pavement construction:

In order to decide the suitability of the aggregate for use in pavement construction, The following tests are conducted to check whether the aggregates are suitable to be utilized in pavement construction:

1.CRUSHING TEST: Crushing under compressive stress is a model to check the eligibility of pavement material for getting passed or failed. A test is organized with IS: 2386 part-IV and applied to find out the crushing strength of aggregates. The aggregate crushing value offers a relevant measure of resistance to crushing under increasingly employed crushing load.

2.ABRASION TEST: Abrasion test is accomplished to examine the rigidity of aggregates as well as determine whether they can be used for various pavement construction works. Los Angeles abrasion test is mostly suitable for executing the hardness property and it is implemented in India (IS: 2386 part-IV).

3.IMPACT TEST: The aggregate impact test is accomplished to verify the resistance to impact of aggregates. Aggregates which have passed 12.5 mm sieve and conserved on 10 mm sieve is filled with a cylindrical steel cup having internal dia 10.2 mm and depth 5 cm that is connected to a metal base of impact testing machine. The material is covered with 3 layers where each layer is tamped for 25 numbers of blows. Metal hammer having weight 13.5 to 14 Kg is set to drop with a free fall of 38.0 cm through vertical guides and the test specimen is dependent on 15 numbers of blows.

4.SOUNDNESS TEST: Soundness test is conducted to analyze the resistance of aggregates against weathering action, by carrying out accelerated weathering test cycles. The Porous aggregates is dependent on freezing and thawing is liable to decompose beforehand. To determine the stability of such aggregates, they are dependent on a faster soundness test as stated in IS: 2386 part-V.

5.SHAPE TESTS: The particle shape of the aggregate mass is set with the proportion of rough and enlarged particles in it. Large and enlarged aggregates may be damaged to higher workability and stability of mixes.

6.SPECIFIC GRAVITY AND WATER ABSORPTION: The design of concrete and bituminous mixes is mostly based on the properties like specific gravity and water absorption of aggregates. The specific gravity of a solid refers to the proportion of its mass to that of an equivalent volume of distilled water at an indicated temperature. As the aggregates may include water-permeable voids, so the following two measures of specific gravity of aggregates are utilized:

1. Apparent specific gravity and
2. Bulk specific gravity.

7.BITUMEN ADHESION TEST: Bitumen is compatible with all general types of road aggregates on condition that they are dry and do not contain dust. Without water, no adhesion issue of bituminous construction occurs.

If the aggregate is wet and cold, the adhesion issue may happen. This issue can be handled by eliminating moisture from the aggregate by drying and raising the mixing temperature. Besides, the existence of water leads to removal of binder from the coated aggregates. This problem happens if bitumen mixture is absorbent to water.

To get more information, click on the following link civilblog.org/

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PUBLISHED BY
RAJIB DEY
WWW.CONSTRUCTIONCOST.CO
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