6. LPC Bituminous Mixtures Design Guide, Sept 2007. - Aapaq.org

More documents

Recommendations

Info

LPC Bituminous Mixtures Design Guide– General remarks –PolychloropreneSBR rubberNatural rubberCrumb rubberElastomer-modified binders:Physical mixes are to be distinguished from elastomeric bitumens obtained by meansof cross-linking.Physical mixes are typically heterogeneous to a scale of several micrometers. Thefineness of the elastomeric bitumen structure will exert a direct influence both on thestability of the asphalt mixture and on its physical properties over the entiretemperature range.Cross-linked elastomeric bitumens exhibit a structure resulting from a dual form ofextremely fine links, on the order of one micrometer. This reaction is irreversible.Cross-linked elastomeric bitumen displays higher tensile strength and stiffness andincreased ductility in comparison with the initial binder.Elastomeric bitumen modification induces differences in rheological behavior. Incomparison with pure bitumen, BmP SBS at low temperature exhibits lower modulusvalues, hence greater flexibility; this situation becomes reversed at hightemperatures. For a given bitumen sample, this modification in rheological behaviordepends on both polymer nature and content.Plastomer-modified binders:Ethylene copolymer bitumen (EVA, EMA and EBA):At low polymer content (< 5%), the modification in material properties is due primarilyto the increase in asphaltene concentration within the bitumen phase. In this case,the choice of the base bitumen is predominant.At high polymer levels, the polymer component is plasticized by a fraction of themaltenes found in the bitumen and the choice of polymer influences binderproperties. A decrease in penetrability coupled with a strong increase in ring and balltemperature can be observed.Ethylene – polybutylene (PIB) copolymeric bitumens:The addition of PIB in road bitumen materials serves to lower the vulnerability to coldweather.The joint use of PIB and EVA enables improving simultaneously the behavior at bothhigh and low temperature.With the exception of PIB-EVA binders, copolymeric bitumen mixes are rarely stablewhen stored (except for content levels < 3% EVA and binders with low asphalteneconcentrations). It thus becomes necessary to stir or remix the binder.Rubber bitumen:Non-storable rubber bitumen:Produced using a crumb rubber obtained by means of grating both natural andsynthetic rubber, rubber bitumen displays an elastomeric characteristic, along with- 28 -
LPC Bituminous Mixtures Design Guide– General remarks –significant viscosity at high temperature and considerable flexibility at lowtemperature.Storable rubber bitumen:Produced using ground worn tires from trucks and cars, heavy oil and a syntheticelastomer, rubber bitumen displays extreme elongation upon failure at lowtemperature.1.4.2.3 Pigmentable bitumenThis category of bitumens is obtained from untreated material samples andcharacterized by a very low asphaltene content. The grades are the same as withconventional road bitumens.The material is colored by means of metallic oxides at an approximate massconcentration of 2,5% to 6% of the total mixture.1.4.2.4 Synthetic bindersThese binders are obtained by mixing petroleum and petrochemical fractions withoutasphaltenes. They appear as a thin transparent film, which makes it possible to retainthe natural hue of the aggregate; moreover, they can be colored by adding 2%pigments.1.4.2.5 Bituminous binders with mineral loadsThese ready-to-use binders are obtained as a plant mix using pure bitumen andmineral loads, e.g. lime. Binder content differs from bitumen content.1.4.2.6 Agrochemical bindersThese binders are made from vegetal matter without any petrochemical byproduct.The result is transparent and may be colored. Its applicability is currently undergoingevaluation.1.4.2.7 Kerosene-proof bitumenThese bitumens have been specially designed to withstand the risk of dissolution dueto kerosene losses on parking surfaces and on airport strips/runways. They may beapplied in the composition of airport asphalt concretes.1.4.2.8 Rule for bitumen mixesIt may prove useful to conduct certain tests on the basis of recomposedbitumens with known penetrability or ring and ball temperatures (e.g. fora rutting test using a bitumen with a preset ring and ball temperaturevalue).- 29 -
Page 1 and 2: LPC Bituminous Mixtures Design Guid
Page 7 and 8: Table of ContentsPREFACE ..........
Page 9 and 10: 3.4.4 Discontinuity ...............
Page 11 and 12: Table of illustrationsFigure 1: Gyr
Page 13 and 14: Table 40 - Adjustment to average te
Page 15: LPC Bituminous Mixtures Design Guid
Page 79 and 80:
LPC Bituminous Mixtures Design Guid
Page 81 and 82:
Page 83 and 84:
Page 85 and 86:
Page 87 and 88:
Page 89 and 90:
Page 91 and 92:
Page 93 and 94:
Page 95 and 96:
Page 97 and 98:
Page 99 and 100:
Page 101 and 102:
Page 103 and 104:
Page 105 and 106:
Page 107 and 108:
Page 109 and 110:
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
Page 117 and 118:
Page 119 and 120:
Page 121 and 122:
Page 123 and 124:
Page 125:
Page 128 and 129:
Page 130 and 131:
Page 132 and 133:
Page 134 and 135:
Page 136 and 137:
Page 138 and 139:
Page 140 and 141:
Page 142 and 143:
Page 144 and 145:
Page 146 and 147:
Page 149 and 150:
Page 151 and 152:
Page 153 and 154:
Page 155 and 156:
Page 157 and 158:
Page 159 and 160:
Page 161 and 162:
Page 163 and 164:
Page 165 and 166:
Page 167 and 168:
Page 169 and 170:
Page 171 and 172:
DefinitionIdentificationDesignation
Page 173 and 174:
Page 175 and 176:
Page 177 and 178:
Page 179 and 180:
Page 181 and 182:
Page 183 and 184:
Page 185 and 186:
Page 187 and 188:
Page 189 and 190:
Page 191 and 192:
Page 193 and 194:
Page 195 and 196:
Page 197 and 198:
show all

6. LPC Bituminous Mixtures Design Guide, Sept 2007. - Aapaq.org

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?