Highways Agency

Smith, L.L., Ramer, R.M. (1992) Recycled Plastics for Highway Agencies, 71th Annual Meeting, TRB, Paper No. 920496. 

The soundness test adopted in BS 812 [8.4] uses magnesium sulfate. The Highways Agency Specification [8.7] gives soundness limits for coarse and fine aggregate of 65 and 75 % respectively. 

The UK Highways Agency s specification [8.7] refers to unbound material for subbase and road-base (Table 8.4). A CEN specification is in preparation (see section 8.8.1). Specifications for use in tropical and sub-tropical countries are described in [8.16]. 

The Highways Agency s Specification 1991 [8.7] identifies strength, durability and cleanliness as being important factors, but places the responsibility on the specifying engineer to assess the requirements for a particular application. A CEN Standard is in preparation (section 8.8.1). 

Dense limestones weather well and easily meet the requirement in the Highways Agency s Specification [8.7] of a magnesium sulfate soundness value [8.4] greater than 75 %. 

Highways Agency, Specification for Highway Works, HMSO, London, 1991. 

Rehable figures for the generation of RAP are not readily available fi om all state highway agencies or local jurisdictions. Based on incomplete data, it is estimated that as much as 41 million metric tons (45 million tons) of RAP may be produced each year in the United States [153-158]. 

Presently, there are more than 4 million miles of roadways in the United States, and 60% of those roads are paved. In building and maintaining roads, highway agencies and contractors use a wide variety of manufactured materials. Increasingly, these materials include industrial by-products and recycled pavements and waste, as well as additives to enhance the performance of the materials. A 1994 survey found that more than 24 waste materials or industry by-products have been used in at least 36 different highway sustainable applications. 

Drysdale, D. (2013). Introducing lean improvement into the U.K. highways agency supply chain. Proceedings of the 21st International Group for Lean Construction Conference, conference, IGLC 21 Fortaleza, Brazil, pp. 1067-1074. 

Figure 4.3 Visual and delamination survey of a cross beam on a motorway bridge suffering from deicing salt ingress (developed view of beam). Courtesy of the Highway Agency.

Figure 4.8 Reference Electrode Potential survey of a Bridge Pier, also recording cover meter chloride concentrations at three different depths. Courtesy Highways Agency AmeyMouchel.

In the United States many highway agencies have applied penetrating sealers to concrete bridge decks. There has been no definitive research to show whether sealers work on trafficked surface or for how long they are effective. 

Overlays may be of polymer modified concretes, low slump dense concrete (the Iowa mixes), or microsilica concretes. They vary in cost and ease of application. State highway agencies generally develop one or two mix designs that suit their purposes and make competitive bidding possible. 

According to the Highways Agency Bridge Advice Note HA BA 83/02 these anodes have a life of up to 15 years and a cost of 20- 40/m. ... 

Table 7.2 Impressed current anode types and characteristics (see Notes 1-8) from haba 83/02 (2000). Courtesy of the Highways Agency... 

Highways Agency (2001). Cathodic Protection for Use in Reinforced Concrete Highway Structures HABA83/02. Design Manual for Roads and Brides. Volume 3 -Highway Structures Inspection and Maintenance (Section 3 Repair, Part 3). 

Concrete Overlays (used on North American highway bridges according to specifications developed by highway agencies). 

The Highways Agency in the United Kingdom has developed another classification system of materials for highway earthworks. This system, apart from soil materials, also includes stabilised soils or any combination of materials (Highways Agency 2009a). 

The proposed Highways Agency classification system also provides information for typical use of materials and property requirements, together with acceptability limits and compaction requirements. 

The classification table developed is known as Table 6/1 and consists of 32 pages. Details regarding Table 6/1 and many more can be found in the manual MCHW, Vol. 1-Series 600 and MCHW Vol. 2-Series NG 600 (Highways Agency 2009 a,c). 

The Highways Agency in the United Kingdom uses a different correlation equation developed by TRL (Highways Agency 2008), which is as follows ... 

It is stated that the accuracy of the above equation reduces for CBR values below 10%. More details regarding the apparatus and execution of the test can be found in relevant standards such as ASTM D 6951 (2009), CEN EN ISO 22476-2 (2011) and DMRB HD29/08 (Highways Agency 2008). 

Equation 1.1 proposed by Powel et al. (1984) is based on the work carried out by Jones (1958) and is used in the current UK pavement design methodology (Highways Agency 2006). The validity of the equation is restricted to fine soil material with laboratory CBR... 

The surface stiffness modulus is calculated using the following general equation (Highways Agency 2009b) ... 

The stiffness modulus of the material can be calculated from the averaged deflections measured over a series of loading patterns (Highways Agency 2009b). 

Adequacy or acceptability of compaction may also be based on MCV determined in situ (Highways Agency 2009b Matheson and Winter 1997). 

Source Adapted from Highways Agency, The Manual of Contract Documents for Highway Works (MCHW),Volume I Spedfica-tion for Highway Works, Series 600 Earthworks. London Department for Transport, Highways Agency, 2009a. 

Highways Agency. 2006. Design Manual for Roads and Bridges (DMRB), Volume 7 Pavement Design and Maintenance, Section 2, Part 3, HD 26/06. London Department for Transport, Highways Agency. 

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