Category:407 Tack Coat - Revision history

Hoskir: /* 407.1.4 Construction Requirements (Sec 407.4) */ fixed spelling error

2024-09-17T20:55:40Z

407.1.4 Construction Requirements (Sec 407.4): fixed spelling error

← Older revision		Revision as of 15:55, 17 September 2024
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	\|[[image:407.1.4.6.3.jpg\|center\|375px\|thumb\|<center>'''Fig. 407.1.4.6.3'''</center>]]\|\|[[image:407.1.4.6.4.jpg\|center\|375px\|thumb\|<center>'''Fig. 407.1.4.6.4'''</center>]]		\|[[image:407.1.4.6.3.jpg\|center\|375px\|thumb\|<center>'''Fig. 407.1.4.6.3'''</center>]]\|\|[[image:407.1.4.6.4.jpg\|center\|375px\|thumb\|<center>'''Fig. 407.1.4.6.4'''</center>]]
	\|-		\|-
	\|colspan="2"\|<center>'''Figs. 407.1.4.6.1 through 407.1.4.6.4, Examples of ~~Heavey~~/Unacceptable Tracking'''</center>		\|colspan="2"\|<center>'''Figs. 407.1.4.6.1 through 407.1.4.6.4, Examples of Heavy/Unacceptable Tracking'''</center>
	\|}		\|}

Smithk: /* 407.1.5 Method of Measurement (Sec 407.5) */ Per CM, minor correction. To round gallons to nearest gallon, not nearest 10 gallons

2016-08-31T12:13:23Z

407.1.5 Method of Measurement (Sec 407.5): Per CM, minor correction. To round gallons to nearest gallon, not nearest 10 gallons

← Older revision		Revision as of 07:13, 31 August 2016
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	:<math>G_c=\frac{(1675-1450)\times(1-0.00)}{((125-60)\times0.0003)+1}</math>		:<math>G_c=\frac{(1675-1450)\times(1-0.00)}{((125-60)\times0.0003)+1}</math>
	:G<sub>c</sub>=220.7 Gallons		:G<sub>c</sub>=220.7 Gallons
	:G<sub>c</sub>=~~220~~ Gallons		:G<sub>c</sub>=221 Gallons

	Now suppose that the emulsion is being cut by 20% with water (C = 0.20). Therefore:		Now suppose that the emulsion is being cut by 20% with water (C = 0.20). Therefore:
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	:G<sub>c</sub>=176.6 Gallons		:G<sub>c</sub>=176.6 Gallons
	:G<sub>c</sub>=~~180~~ Gallons		:G<sub>c</sub>=177 Gallons

	==407.2 Materials Inspection for Sec 407==		==407.2 Materials Inspection for Sec 407==

Smithk: updated links

2016-06-09T13:16:28Z

updated links

← Older revision		Revision as of 08:16, 9 June 2016
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	:* Check the spray temperature of the emulsion. Heat the emulsion to a maximum temperature of 160º F for spray application. The higher temperature of the tack product should result in quicker set time and reduce tracking.		:* Check the spray temperature of the emulsion. Heat the emulsion to a maximum temperature of 160º F for spray application. The higher temperature of the tack product should result in quicker set time and reduce tracking.
	:* Apply soap solution to the tires of the construction equipment. In some cases, the application of soap has been known to reduce the tack pick-up from tires.		:* Apply soap solution to the tires of the construction equipment. In some cases, the application of soap has been known to reduce the tack pick-up from tires.
	:* Pre-wet the surface in accordance with [http://www.modot.org/business/standards_and_specs/~~Sec0407~~.pdf Sec 407]. Pre-wetting the surface prior to tack application has been theorized to break the surface charge and cause the tack coat to flow and adhere to the surface better to reduce tracking.		:* Pre-wet the surface in accordance with [http://www.modot.org/business/standards_and_specs/SpecbookEPG.pdf#page=7 Sec 407]. Pre-wetting the surface prior to tack application has been theorized to break the surface charge and cause the tack coat to flow and adhere to the surface better to reduce tracking.

	If all of the above items are conducted with further heavy track off; then the contractor needs to either wait until the tack is completely set, change emulsion types or use a spray paver.		If all of the above items are conducted with further heavy track off; then the contractor needs to either wait until the tack is completely set, change emulsion types or use a spray paver.
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	===407.1.5 Method of Measurement (Sec 407.5)===		===407.1.5 Method of Measurement (Sec 407.5)===
	The quantity of emulsion to be paid for will be determined in accordance with [http://www.modot.~~state.mo.us~~/business/standards_and_specs/~~Sec1015~~.pdf Standard Specification Section 1015.6] and rounded to the nearest whole gallon. For volumetric determination, the following equation should be used:		The quantity of emulsion to be paid for will be determined in accordance with [http://www.modot.org/business/standards_and_specs/SpecbookEPG.pdf#page=14 Standard Specification Section 1015.6] and rounded to the nearest whole gallon. For volumetric determination, the following equation should be used:

	:<math>G_c=\frac{(G_b-G_e)\times(1-C)}{((T-60)\times0.0003)+1}</math>		:<math>G_c=\frac{(G_b-G_e)\times(1-C)}{((T-60)\times0.0003)+1}</math>
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	===407.3.3 Products===		===407.3.3 Products===
	Asphalt emulsions commonly used for tack coats areSS-1, CSS-1, SS-1h and CSS-1h. Polymers are allowed to be added to any emulsion which give benefits to both bond strength and achieving mat density by keeping the material from moving under the vibratory compactor. Hard penetration asphalt emulsions are also allowed in accordance with Sec 1015. Refer to [http://modot.~~mo.gov~~/business/standards_and_specs/~~Sec0407~~.pdf Standard Specification Section 407] for additional information regarding tack coats.		Asphalt emulsions commonly used for tack coats areSS-1, CSS-1, SS-1h and CSS-1h. Polymers are allowed to be added to any emulsion which give benefits to both bond strength and achieving mat density by keeping the material from moving under the vibratory compactor. Hard penetration asphalt emulsions are also allowed in accordance with Sec 1015. Refer to [http://www.modot.org/business/standards_and_specs/SpecbookEPG.pdf#page=7 Standard Specification Section 407] for additional information regarding tack coats.

Smithk: /* 407.1.3 Equipment (Sec 407.3) */

2016-03-18T18:53:56Z

407.1.3 Equipment (Sec 407.3)

← Older revision		Revision as of 13:53, 18 March 2016
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	See [[460.4 Paving Equipment\|Distributor]] in Paving Equipment. Several distributor equipment adjustments and settings are critical to achieve a uniform tack coat placement. The best practice for uniform coverage is to use a “double or triple lap” coverage which means that every portion of the pavement receives spray from two or three nozzles. The triple lap coverage is illustrated below:		See [[460.4 Paving Equipment\|Distributor]] in Paving Equipment. Several distributor equipment adjustments and settings are critical to achieve a uniform tack coat placement. The best practice for uniform coverage is to use a “double or triple lap” coverage which means that every portion of the pavement receives spray from two or three nozzles. The triple lap coverage is illustrated below:

	[[image:407.1.3.jpg\|center\|~~750px~~]]		[[image:407.1.3.jpg\|center\|700px]]

	Specific guidance for distributor set-up are as follows:		Specific guidance for distributor set-up are as follows:

Smithk: Per CM, updated to align with spec book. Updated to achieve proper application and coverage of tack coat material to improve bond strength between pavement layers and produce longer service life.

2016-03-18T18:52:56Z

Per CM, updated to align with spec book. Updated to achieve proper application and coverage of tack coat material to improve bond strength between pavement layers and produce longer service life.

Show changes

Smithk: /* 407.1.4 Construction Requirements (Sec 407.4) */

2015-12-23T14:33:27Z

407.1.4 Construction Requirements (Sec 407.4)

← Older revision		Revision as of 09:33, 23 December 2015
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	The tack coat must be uniformly applied to the existing surface at the rate specified in the		The tack coat must be uniformly applied to the existing surface at the rate specified in the
	contract. Generally, the application rate between the existing pavement and the first lift should be in the range of 0.05 to 0.10 gal/yd<sup>2</sup>. . A tack coat is required between each lift of bituminous pavement. The application rate between lifts should be in the range of 0.02 to 0.05 gal/yd<sup>2</sup>.		contract. Generally, the application rate between the existing pavement and the first lift should be in the range of 0.05 to 0.10 gal/yd<sup>2</sup>. A tack coat is required between each lift of bituminous pavement. The application rate between lifts should be in the range of 0.02 to 0.05 gal/yd<sup>2</sup>.

	Depending on the condition of the existing surface, the application rate may need to be adjusted from the specified rate. This is acceptable as long as approval is obtained from the RE		Depending on the condition of the existing surface, the application rate may need to be adjusted from the specified rate. This is acceptable as long as approval is obtained from the RE

Smithk: /* 407.1.4 Construction Requirements (Sec 407.4) */ Per CM, clarification to reflect current supplemental provision language

2015-12-23T14:33:09Z

407.1.4 Construction Requirements (Sec 407.4): Per CM, clarification to reflect current supplemental provision language

← Older revision		Revision as of 09:33, 23 December 2015
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	The tack coat must be uniformly applied to the existing surface at the rate specified in the		The tack coat must be uniformly applied to the existing surface at the rate specified in the
	contract. Generally, the application rate between the existing pavement and the first lift should be in the range of 0.05 to 0.10 gal/yd<sup>2</sup>. ~~It is strongly recommended to apply a light~~ tack coat between each lift of bituminous pavement. The application rate between lifts should be in the range of 0.02 to 0.05 gal/yd<sup>2</sup>.		contract. Generally, the application rate between the existing pavement and the first lift should be in the range of 0.05 to 0.10 gal/yd<sup>2</sup>. . A tack coat is required between each lift of bituminous pavement. The application rate between lifts should be in the range of 0.02 to 0.05 gal/yd<sup>2</sup>.

	Depending on the condition of the existing surface, the application rate may need to be adjusted from the specified rate. This is acceptable as long as approval is obtained from the RE		Depending on the condition of the existing surface, the application rate may need to be adjusted from the specified rate. This is acceptable as long as approval is obtained from the RE

Smithk: minor clarifications to differentiate EPG articles (that are referenced as "articles", not "sections") from specifications (that are referenced as "sections")

2010-04-02T19:24:31Z

minor clarifications to differentiate EPG articles (that are referenced as "articles", not "sections") from specifications (that are referenced as "sections")

← Older revision		Revision as of 14:24, 2 April 2010
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	===407.1.2 Material (Sec 407.2)===		===407.1.2 Material (Sec 407.2)===
	See [[#407.2 Materials Inspection for Sec 407\|Materials Inspection]] and [[:Category:1015 Bituminous Material\|1015 Bituminous Material]].		See [[#407.2 Materials Inspection for Sec 407\|Materials Inspection]] and [[:Category:1015 Bituminous Material\|EPG 1015 Bituminous Material]].

	===407.1.3 Equipment (Sec 407.3)===		===407.1.3 Equipment (Sec 407.3)===
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	==407.2 Materials Inspection for Sec 407==		==407.2 Materials Inspection for Sec 407==

	Tack Coat material shall be sampled and inspected in accordance with [[:Category:1015 Bituminous Material\|1015 Bituminous Material]].		Tack Coat material shall be sampled and inspected in accordance with [[:Category:1015 Bituminous Material\|EPG 1015 Bituminous Material]].

	==407.3 Maintenance Tacking or Tack Coating==		==407.3 Maintenance Tacking or Tack Coating==

EPG-Admin at 19:45, 8 November 2007

2007-11-08T19:45:13Z

← Older revision		Revision as of 14:45, 8 November 2007
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	This item is used for impervious surfaces such as portland cement concrete, asphaltic concrete or bituminous surfaces prior to resurfacing. ~~The~~ grade of emulsified asphalt is selected by the contractor.		This item is used for impervious surfaces such as portland cement concrete, asphaltic concrete or bituminous surfaces prior to resurfacing to improve the bond between the existing surface and the roadway pavement. In contracts the grade of emulsified asphalt is selected by the contractor.

	==407.1 Construction Inspection for Sec 407==		==407.1 Construction Inspection for Sec 407==
	===407.1.1 Description (Sec 407.1)===		===407.1.1 Description (Sec 407.1)===
	The purpose of a tack coat is to improve the bond between the		The purpose of a tack coat is to improve the bond between the existing surface and the mat.
	existing surface and the mat.

	===407.1.2 Material (Sec 407.2)===		===407.1.2 Material (Sec 407.2)===
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	Tack Coat material shall be sampled and inspected in accordance with [[:Category:1015 Bituminous Material\|1015 Bituminous Material]].		Tack Coat material shall be sampled and inspected in accordance with [[:Category:1015 Bituminous Material\|1015 Bituminous Material]].

			==407.3 Maintenance Tacking or Tack Coating==
			Maintenance uses tacking or tack-coating by applying a light spray application of cutback or emulsified asphalt to impervious surfaces such as Portland cement concrete, asphaltic concrete, or bituminous surfaces prior to resurfacing.

			===407.3.1 Purpose===
			The purpose of the tack coat is to improve the bond between the existing surface and the roadway pavement. A tack coat shall be applied to provide a bond between old and new wearing courses. The best results occur when the tack is applied to a dry and clean surface, free of loose material.

			===407.3.2 Application Rates===
			The application rate will vary from 0.03 to 0.15 gal/yd<sup>2</sup>, depending on the condition of the old pavement surface. The pavement course surface should be evaluated to determine the amount of tack to be applied. A viscous material should be used because very little penetration of the asphaltic oil into the pavement surface is expected. The tack coat should be allowed to become tacky or sticky before the surface course is laid. Emulsions are recommended for tacking on heavily traveled routes. Too much tack can create a slippage plane between the old pavement and the new pavement overlay as the tack coat acts as a lubricant instead of an adhesive. Also too much tack could result in bleeding of the tack through to the new overlay surface, which can produce a slick pavement condition. After application of the tack, time must be allowed for the tack to break. Breaking is the phenomenon when the asphalt and water in the emulsion separate, beginning the curing process (brown to black color). Traffic should be kept off the tacked area.

			===407.3.3 Products===
			Asphalt emulsions commonly used for tack coats are diluted SS-1, SS-1h, SCC-1 and CSS-1h. Refer to [http://modot.mo.gov/business/standards_and_specs/Sec0407.pdf Standard Specification Section 407] for additional information regarding tack coats.

EPG-Admin at 11:46, 1 November 2007

2007-11-01T11:46:45Z

← Older revision		Revision as of 06:46, 1 November 2007
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			This item is used for impervious surfaces such as portland cement concrete, asphaltic concrete or bituminous surfaces prior to resurfacing. The grade of emulsified asphalt is selected by the contractor.

	==407.1 Construction Inspection for Sec 407==		==407.1 Construction Inspection for Sec 407==
	===407.1.1 Description (Sec 407.1)===		===407.1.1 Description (Sec 407.1)===
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	===407.1.5 Method of Measurement (Sec 407.5)===		===407.1.5 Method of Measurement (Sec 407.5)===
	The quantity of emulsion to be paid for will be determined in accordance with[http://www.modot.state.mo.us/business/standards_and_specs/Sec1015.pdf Standard Specification Section 1015.7.2] and rounded to the nearest 10 gallons. The following equation		The quantity of emulsion to be paid for will be determined in accordance with [http://www.modot.state.mo.us/business/standards_and_specs/Sec1015.pdf Standard Specification Section 1015.7.2] and rounded to the nearest 10 gallons. The following equation
	should be used:		should be used: