{"id":2007,"date":"2021-09-03T14:00:54","date_gmt":"2021-09-03T14:00:54","guid":{"rendered":"https:\/\/ldaequipamentos.com.br\/en\/?p=2007"},"modified":"2021-09-03T14:24:24","modified_gmt":"2021-09-03T14:24:24","slug":"binding-layer","status":"publish","type":"post","link":"https:\/\/ldaequipamentos.com.br\/en\/binding-layer\/","title":{"rendered":"Binding Layer"},"content":{"rendered":"

[vc_row][vc_column width=”1\/6″][vc_single_image image=”199″ onclick=”custom_link” img_link_target=”_blank” link=”http:\/\/www.ldaequipamentos.com.br\/blog”][\/vc_column][vc_column width=”2\/3″][vc_single_image image=”2009″ img_size=”full” alignment=”right”][vc_column_text css=”.vc_custom_1630003406122{margin-top: 40px !important;margin-bottom: 20px !important;}”]The purpose of the pavement layer design is to reduce the pressure on the lower layer, thus reducing the load required in the first layer, so that the bed only accepts part of the demand. The pavement can be defined as the following layers:\"\" <\/em><\/p>\n

1. Coating
\n2. Base
\n3. Subbase
\n4. Subgrade Reinforcement
\n5. Sub-deal<\/p>\n

Binding layer:<\/strong> as the name suggests, this layer has the function of binding the asphalt coating with the base.<\/p>\n

Asphalt spreaders<\/strong> are the equipment responsible for printing the roadway under construction. It is this equipment that, in paving operations, sprays emulsion on the base of asphalted roads.<\/p>\n

1 – Definition<\/strong><\/p>\n

The sprinklers have the purpose of applying an asphalt material in the form of a film on the surface of a landfill or an untreated material (sub-base or gravel) or on an untreated granular base (compacted stone or crushed gravel).<\/p>\n

2 – Functions<\/strong><\/p>\n

This application can have one or more of the following purposes:<\/p>\n

<\/div>\n

Waterproofed surface
\nClose capillary spaces
\nGlue the loose particles to the surface
\nHarden the surface
\nEase maintenance
\nPromote adhesion between the surface on which the first layer of asphalt will be placed<\/p>\n

Of all these functions, in a continuous paving operation, the most important is to promote adhesion between the asphalt layers.<\/p>\n

3 – Structural Capacity<\/strong><\/p>\n

The application of the products with the spreaders, under no circumstances, has structural support in the pavement layers.<\/p>\n

4 – Type and quantity of material to be applied<\/strong><\/p>\n

<\/div>\n

The type and quantity of asphalt material to be applied depends mainly on the texture and porosity of the material to which it will be applied.<\/p>\n

Specifications indicate a quantity ranging between 0.90 and 2.7 l \/ m\u00b2.<\/p>\n

Of course, denser, closed surfaces need less application as it will absorb less than rough, open surfaces.<\/p>\n

5 – Maintenance and opening for traffic<\/strong><\/p>\n

The primed area can be closed to traffic between 24 and 48 hours so that the bitumen can penetrate and harden the surface.<\/p>\n

Excess bituminous material can form puddles that should be removed with brooms or manual brooms.<\/p>\n

<\/div>\n

The imprinted area must be cleaned with compressed air. If the weather is cold or the material has not fully penetrated the base surface, a longer period may be necessary.<\/p>\n

Any excess bituminous material remaining on the surface after this period must be removed using an absorbent material prior to traffic clearance.<\/p>\n

The area that was printed should be preserved until another layer is placed. The conservation work must include some material to prevent the adhesion of the layer on car tires so as not to break the surface of the asphalt binder.<\/p>\n

In other words, any prepared surface areas, if they are damaged by vehicular traffic or otherwise, must be repaired before the surface layer is placed.<\/p>\n

6 – Weather conditions<\/strong><\/p>\n

It is not possible to use the spreader to apply the emulsion on rainy days.<\/p>\n

7 – Factors affecting uniform application<\/strong><\/p>\n

Asphalt Spray Temperature
\nLiquid pressure along the spray bar
\nAngle of spreader bar nozzles
\nHeight of the nozzle holes on the applied surface
\nSpreader truck speed<\/p>\n

7.1 – Asphalt Spray Temperature<\/strong><\/p>\n

<\/em><\/span><\/p>\n

\n

The asphalt distributors have protected tanks to maintain the material temperature and are equipped with torches to reach or maintain the proper application temperature.<\/p>\n

7.2 – Liquid pressure along the spreader bar<\/strong><\/p>\n

To maintain continuous and constant pressure along the length of the spray bar, variable discharge pumps are used.<\/p>\n

7.3 – Angle of spreader bar nozzles<\/strong><\/p>\n

The spray angle of the nozzle holes must be properly established, generally between 15\u00b0 and 30\u00b0 in relation to the horizontal axis of the spreader bar so that the individual flows do not interfere with each other in the application.<\/p>\n

7.4 – Height of the nozzle holes on the applied surface<\/strong><\/p>\n

The height of holes in the surface determines the width of an individual stream. To ensure correct overlap of each outlet, hole height must be established and maintained throughout the operation.<\/p>\n

<\/p>\n<\/div>\n

7.5 – Spreader truck speed<\/strong><\/p>\n

The vehicle must be equipped with a\u00a0speedometer visible to the driver to\u00a0guarantee constant speed,\u00a0allowing uniform application of the binder in the mechanical and hydrostatic spreaders.<\/p>\n

There is a relationship between the application rate and the spreader speed.<\/p>\n

<\/div>\n

Easier in the option of electronic hydrostatic spreader, such as: dual tank of varied capacity, fifth wheel + tachometer, internal and external control of operations and pneumatic bar.<\/p>\n

8 – Care in the operation of the spreaders<\/strong><\/p>\n

When it comes to asphalt spreaders, the good cost-benefit ratio can be influenced by several factors. Among them is the temperature of the material, maintained by torches that act directly on the storage tank.<\/p>\n

Some construction companies usually load the sprinklers with cold material at the construction site and wait until the torches heat up the entire mass, something that can take hours and is not recommended.<\/p>\n