DEVELOPMENT OF SKID RESISTANT HOT ASPHALT MIXTURES BY BLENDING AGGREGATES FROM DIFFERENT SOURCES AMNON RAVINA- Geokom Ltd. SHIMON NESICHI – Israel National Roads Company MAY 2011

Presentation Topics Summary & Conclusions Background- Shortage of basalt aggregates in Israel's Paving Industry R&D PROJECT : Literature survey Laboratory tests Paving of a 4km experimental project Performance monitoring Implementation in INRC paving projects Summary & Conclusions

Israel’s HMA Paving industry at a Glance : About 25 HMA plants Background- Shortage of basalt aggregates in Israel's HMA Paving Industry (1) Israel’s HMA Paving industry at a Glance : About 25 HMA plants Annual HMA production – 5-6 million tons (about 1 ton per capita) 1.5-2.5 Million tons of surface mixtures (Annually) 3

Basalt Shortage Problem (1): Background- Shortage of basalt aggregates in Israel's HMA Paving Industry (2) Basalt Shortage Problem (1): Only 2 types of aggregates available nationally: Dolomite and Basalt Best Polishing Resistant aggregate – basalt (PSV= 51- 55) Most Availablable Aggregate Dolomite / Limestone (PSV =30-40) 4

Basalt Shortage Problem (2): Background- Shortage of basalt aggregates in Israel's HMA Paving Industry (3) Basalt Shortage Problem (2): Annual demand of Basalt Aggregate- 800000 tons (only 3 quarries) Basalt is the dominant coarse aggregate type used in surface mixtures Growing Demand due to implementation of SMA resurfacing policy 5

DGA (left) Vs. SMA (right)– Hw no. 2- 2006 DOLOMITE- DGA BASALT- SMA DGA (left) Vs. SMA (right)– Hw no. 2- 2006

Basalt Shortage Problem (3): Background- Shortage of basalt aggregates in Israel's HMA Paving Industry (3) Basalt Shortage Problem (3): Effect of shortage problems : Delays in projects Quality problems Price rise 7

Basalt Shortage Problem (4): Background- Shortage of basalt aggregates in Israel's HMA Paving Industry (3) Basalt Shortage Problem (4): Basalt Price Rise 2000-2006 (NIS) DOLOMITE 8

Basalt Shortage Problem – Possible Solutions (5): Background- Shortage of basalt aggregates in Israel's HMA Paving Industry (3) Basalt Shortage Problem – Possible Solutions (5): VTOL Controlled Replacement of Some of the Basalt COARSE Aggregate by Dolomite (i.e.blending) WITHOUT SACRIFICING SKID RESISTANCE 9

SMA GRADATION CURVE PERCENT PASSING (%) SIEVE

Paving of a 4km experimental project (test sections) DEVELOPMENT OF SKID RESISTANT HOT ASPHALT MIXTURES BY BLENDING AGGREGATES FROM DIFFERENT SOURCES R&D PROJECT : Literature survey Laboratory tests Paving of a 4km experimental project (test sections) Performance monitoring of test sections Implementation in INRC’s paving projects 12

R&D PROJECT- LITERATURE SURVEY (1) We didn’t invent the wheel ! Two examples of applying the “blending of aggregates” concept: Liang - Blending proportions of high skid and low skid aggregate- OHIO 2002 Dumitru , Vasile , Sidney - Safer roads for Tasmania Gunn’s Hill project – skid resistance field assessment- 2007 13

R&D PROJECT- LITERATURE SURVEY (2) Blending up to 50% is possible without sacrificing Polishing Resistance! Start with lab tests (e.g. PSV) of varying blends – to determine combinations Don’t release your specs requirements Continue with a monitoring plan of AC-mix plant production, field test section construction and field service performance Approve for routine use (if successful…) 14

R&D PROJECT- LAB TESTS (1) Feasibility study Test Effect of various combinations of basalt /dolomite on PSV Compare the results to the specs 15

R&D PROJECT- LAB TESTS FEASIBILITY STUDY (2) 2 Dolomite quarries 1 Basalt quarry Specs limit- 48 16

R&D PROJECT- LAB TESTS FULL PROJECT DATA (3) 6 Dolomite quarries 1 Basalt quarry Specs limit- 48 17

R&D PROJECT- LAB TESTS – CONCLUSIONS (4) Successful Blending of Basalt and Dolomite is feasible 60% Basalt / 40% Dolomite satisfy the PSV>=48 Limit 18

Paving of a 4km experimental project -DESIGN (1) 2 Dolomite sources (quarries) 1 Basalt source (quarry) 2 HMA types ( SMA, “S- Structural”) 8 Mixtures 19

Paving of a 4km experimental project -DESIGN (2) SMA “BLENDS” 20

Paving of a 4km experimental project -DESIGN (3) S-Str “BLENDS” 21

Paving of a 4km experimental project -DESIGN (4) PROJECT LOCATION (historical) 22

Paving of a 4km experimental project -DESIGN (5) PROJECT LOCATION (2011) ROAD 784 23

Paving of a 4km experimental project -DESIGN (6) Total Production- 9000 Tons Experimental Test Sections – B-D Blending- 7000 tons Total project length- about 4 Km Overlay project- mill/overlay – 5 cm 24

Paving of a 4km experimental project - CONSTRUCTION (1) NO production problems NO workability difficulties NO problems in controlling proportioning – production & QA/QC 25

Paving of a 4km experimental project - CONSTRUCTION (2) AGGREGATE EXTRACTION THE “ZEBRA” MIX

Paving of a 4km experimental project - CONSTRUCTION (3) BOTTOM LINE – EXCELLENT CONSTRUCTION QUALITY ACHIEVED! 27

Paving of a 4km experimental project - CONSTRUCTION (4) Z-SMA Z-SMA B-SMA 28

Performance monitoring of test sections(1) MONITORING PROGRAM Z-SMA SURFACING AGE (MONTH) MPD SAND PATCH PENDULUM GRIPTESTER MK2 ROAR 16 + 28 ROAR - 75 KM/H , 86% FIXED SLIP, 0.5 mm GRIPTESTER- 75KM/H, 0.5 mm 29

Performance monitoring of test sections(2) MU- SMA MIXTURES – 16 Months - ROAR Z-SMA 30

Performance monitoring of test sections(3) MU- S- Str MIXTURES – 16 Months - ROAR Z-SMA 31

Performance monitoring of test sections(4) MU- S- Str MIXTURES – 16 Months – GT-MK2 Z-SMA 32

Performance monitoring of test sections(5) SMA MIXTURES – 16 Months - MPD Z-SMA 33

Performance monitoring of test sections(6) S- Str MIXTURES – 16 Months - MPD Z-SMA 34

Performance monitoring of test sections(6) MU - ALL MIXTURES – 16 / 28 Months Z-SMA MU – ROAR 16 MONTH MU – GT – MK2 , 28 MONTH 35

Performance monitoring of test sections – conclusions (6) The blended (“ZEBRA”) mixtures are: Superior in friction performance to dolomite mixtures Close in friction performance to basalt mixtures These findings are valid after 2.5 years service period in medium trafficked road (AADT=15000) There is no effect of aggregate type on texture depth Z-SMA 36

Implementation in INRC paving projects (from 2010) Updating Design Guidelines: “ZEBRA” mixtures may be used in roads with an AADT of 5000 to 20,000, or in other roads (with less traffic) that require improvement in the SR Basalt mixtures are required only for roads with AADT of over 20000 “ZEBRA” mixtures are included in the INRC general specs 37

Summary & Conclusions (1) Controlled blending of high and low PR aggregates is an accepted procedure internationally Laboratory PSV tests, established the feasibility of 60% Basalt / 40% Dolomite blending ratio 38

Summary & Conclusions (2) Constructing a four kilometer test section with various HMA mixtures: Basalt, Dolomite and 60%-40 % Basalt-Dolomite ("ZEBRA" ) blend demonstrated that the " ZEBRA " mixtures met the all acceptance specification requirements – similar to other control mixtures. Field performance monitoring proved that the SR of the " ZEBRA " mixtures was superior to the Dolomite's and close to Basalt's. 39

Summary & Conclusions (3) Based on these findings, the " ZEBRA " mixtures were introduced to the INRC's specifications and design guidelines. It is estimated that applying the new design guidelines may save about 450000 tons of basalt aggregate- annually. 40

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