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41 Guide to the Prevention and Repair of Salt Damage to Roads and Runways Roads Department Appendices uthor A t al S t aximum Limi M n Locatio aterial M s Criteria/Remark Lewis & Cole (1960) as Chloride NaCl be 0.2% (0.5% may safe) and soils clay Sandy semibase gravel lateritic Australia Western - arid base damaged salt soluble of Observations compacted with tests laboratory and courses salt of amounts various which to gravels was damage No added. been had solution to up containing materials with encountered warn 0.2% and suggest authors 0.5% but tests. their of scope limited the against Soluble given. not analysis salt of Method results Australia Western in damage salt in chloride of rise from capillary mainly groundwater. & Weinert (1967) Clauss Chloride as Sulphate O S 3 y (mostl - gSO M 4 ) % 0.2 0.05% foundations road For but generally materials quartzite for principally Africa South waste mine Lewis & from Cole adopted limit Chloride from suggested limit Sulphate (1960). 0.05%) (ie limit critical the of considerations of content sulphate and stones building for occurred. had damage where materials base 5:1 of analysis by obtained as contents Salt carried was Analysis extracts. soil water: few top from the obtained material on out upward after probably base of inches this in Damage place. took salt of migration saline of use from the resulted case, material. construction Netterberg (1970) an As of indication total sulphate if material Reject conductivity electrical >1.5mmhos/cm at is 0.6-1.5 If 15.8ºC. for mmhos/cm test if reject and sulphates 0.06% If >0.05%. mhos/ m t cm accep material sub-base and base any For Africa. South material. limits salt to correspond limits Conductivity and (1960) Lewis & Cole by suggested Electrical (1967). Clauss & Weinert indirapid a as used be can conductivity major a has it however salinity, of cation the identify not does it that in drawback to only Applicable present. salt of type material construction waste mine quartzite varies relationship conductivity/salinity as material. the on depending Netterberg, & Theron Blight, (1974) Marais soluble Total salt soluble Total sulphate 0.2% 0.15% sub-base and Base Witwatersand materials. see - waste mine quartzite Clauss. & Weinert Africa South the of nature peculiar the stress Authors upon material) waste (mine experience based. are limits suggested the which water on out carried analysis Sulphate & Fookes (eg authors some Note: extract. acid to refer 1979) Netterberg 1977), French are considered salts The sulphate. soluble construction waste mine from quartzite materials. Stewart Blight, (1974) Theron & soluble Total (mostly salt sulphate) safe) be % (3% may 2 c asphalti for used sand For Africa South mixes. various of surfaces asphaltic of Observations bearing sulphate with made ges a o Als sands. specimens on tests aboratory l g containin salt. soluble added of quantities various APPENDIX A: MAXIMUM SALT CONTENT LIMITS WORLDWIDE
42 Guide to the Prevention and Repair of Salt Damage to Roads and Runways Roads Department Appendices uthor A t al S t aximum Limi M n Locatio aterial M s Criteria/Remark - 1083 SABS (South 1976 Bureau African Standards) of soluble Total salt .5% 0 a Afric outh S n o Based (1979). Netterberg in uoted Q n a when salts soluble total that understanding salts harmless other include will determined 0.2% Therefore material. the n i g Netterber of too considered (1974) al t e e Solubl stringent. extracts. water on determined content salt (1976) light B e solubl Total salt .2% 0 e sub-bas and Base materials preof sulphates are discussed salts The Author iron. magnesium and dominantly be also 0.2% can that uggests s d applie predomi is salt the here w - y antl n . chlorides that acknowledge not does limit The ul s . chlorides than deleterious more are phates & Fookes (1977) French - d an traffic with Varies stipulated other conditions Middle the in experience field on Primarily the of assessment on and ast E f o type found conditions and aterials m t tha in possible the to point Authors egion. r t effec specified limits the on mixtures salt f o d an of type predominant the account into take region. the in salts Netterberg (1979) as Sulphate O S 3 o t according BS1377 to According BS1377 soluble Total salt 0.3% 0.5% 2.0% treated cement and Lime cohesive if materials cohesive not If fines - material Untreated discussed. not limits suggested for Criteria water on out carried are Determinations discussed that to similar Materials extracts. (1974). al et Netterberg in William Sir & Halcrow (date Partners unknown) soluble Acid sulphate soluble Acid sulphate soluble Acid sulphate 0.3% 0.5% 2.0% base and course Wearing material course hard and Roadbase shoulder Sub-base Middle the in construction road of Experience East.
Page 2 and 3: Roads Department The Prevention and
Page 4 and 5: Roads Department ROADS DEPARTMENT U
Page 6 and 7: Roads Department 3.3.3 Field Determ
Page 8 and 9: FOREWORD Roads Department The preve
Page 10 and 11: Roads Department 1. INTRODUCTION 1.
Page 12 and 13: Roads Department 2. OCCURRENCE AND
Page 14 and 15: Roads Department Preliminary field
Page 16 and 17: Roads Department tained up to 0.5%
Page 18 and 19: Roads Department In addition to the
Page 20 and 21: Roads Department The various salt t
Page 22 and 23: Roads Department 2.5.4 Pavement Sur
Page 24 and 25: Roads Department to temperature. Th
Page 26 and 27: Roads Department 3. LABORATORY AND
Page 28 and 29: Roads Department E.C can also be co
Page 30 and 31: Roads Department 4. RISK EVALUATION
Page 32 and 33: Roads Department The salt content v
Page 34 and 35: Roads Department 5. PREVENTATIVE DE
Page 36 and 37: Roads Department 20 19 12 11 10 9 8
Page 38 and 39: Roads Department 6. REPAIR OF DAMAG
Page 40 and 41: Roads Department 8. REFERENCES Refe
Page 44 and 45: Roads Department APPENDIX B Appendi
Page 46 and 47: Roads Department Appendices Stage 3
Page 48 and 49: Roads Department APPENDIX E - ABBRE

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