BS 434-2:2006 pdf free.Bitumen roademulsions – Code of practice for the use ofcationic bitumen emulsions on roadsand other paved areas.
BS 434-2 This part of BS 434 provides recommendations and guidance on thegeneral usage of cationic bituminous emulsions on roads and otherpaved areas.The emulsions covered conform to BS 434-1, or BS EN 13808(modified and non-modified), or are proprietaryemulsions.
This British Standard provides guidance on where the various processesusing bituminous emulsions are suitable for use and indicates wheresuitable design procedures may be found.Advice is also given on thosesituations in which the processes are unsuitable or marginally suitable.Where there is an option, performance or outcome specifications havebeen used rather than input or recipe specifications. This follows thegeneral approach adopted for European Standards and the generalmove towards performance specifications by many specifiers.Anionic emulsions are covered only for exceptional circumstances.Cationic emulsions have been specified for most purposes, although insome cases an anionic alternative may be used.
The following referenced documents are indispensable for the application of this document. For dated references, only the editioncited applies. For undated references, the latest edition of the referenced document ( including any amendments) applies.
BS 434-1:1984, Bitumen road emulsions (anionic and cationic)-Part 1 : Specification for bitumen road emulsions
BS 594-2:2003, Hot rolled asphalt for roads and other paved areas – Part 2: Specification for transport,laying and compactionof hot rolled asphalt.
Thus a K1:70 emulsion is a rapid breaking cationic emulsion with anominal binder content of 70%.An A2:50 emulsion is a mediumbreaking anionic emulsion with a nominal binder content of 50%.The stability of emulsions can be changed by altering the type orquantity of emulsifier used in their manufacture.In recent years thedevelopment of tests to measure the break of the emulsion has resultedin numerical values, of breaking value or breaking index, being attributed to emulsion. This more accurately reflects their stability thanthe traditional allocation of 1,2 or 3 in BS 434-1:1984 (see above) asan indication of stability, and has allowed the stability of emulsion to bedefined numerically (breaking index) in BS EN 13808.BS 434-2 pdf download.