NLA Test & Measurement 2011 Workshops Roodevallei conference & meeting Hotel 19 th 20 th September 2011

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Hannah Baldwin
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changes for granular methods Grading revisions General changes for apparatus

1 NLA Test & Measurement 2011 Workshops Roodevallei conference & meeting Hotel 19 th 20 th September 2011 Currents test methods on SABS website Summary of changes for granular methods Grading revisions General changes for apparatus Wet sieving Dry sieving Moisture determination Atterberg Tests MDD & OMC CBR 1

2 revisions SANS 3001-PR1 Determination of uncertainty of measurement, repeatability, reproducibility and bias SANS 3001-PR5 Computation of soil-mortar percentages, coarse sand ratio, grading modulus and fineness modulus SANS 3001-PR10 Checking, handling, maintenance and verification of test sieves SANS 3001-AG1 Particle size analysis of aggregates by sieving SANS 3001-AG2 Determination of the average least dimension of aggregates by direct measurement SANS 3001-AG3 Determination of the average least dimension of aggregates by computation SANS 3001-AG4 Determination of the flakiness index of coarse aggregate revisions 2

3 5 6 SANS 3001-AG20 Determination of the bulk density, apparent density & water absorption of aggregate particles retained on the 5 mm sieve for road construction materials SANS 3001-AG21 Determination of the bulk density, apparent density & water absorption of aggregate particles passing the 5 mm sieve for road construction materials revisions 1 SANS 3001-BT20 Certification of a binder distributor revisions SANS 3001-BT21 Validation of a binder distributor dipstick SANS 3001-BT22 Power and road speed indicator tests for a binder distributor SANS 3001-BT23 Pump system performance of a binder distributor SANS 3001-BT24 Measurement of transverse distribution ('Bucket test') for a binder distributor 3

4 Revisions SANS 3001-GR1 Wet preparation and particle size analysis SANS 3001-GR2 Dry preparation and dry particle size analysis of gravels and sands SANS 3001-GR10 Determination of the one-point liquid limit, plastic limit, plasticity index and linear shrinkage SANS 3001-GR11 Determination of the liquid limit with the two-point method SANS 3001-GR12 Determination of the flow curve liquid limit Revisions SANS 3001-GR20 Determination of the moisture content by oven-drying SANS 3001-GR30 Determination of the maximum dry density and optimum moisture content SANS 3001-GR31 Determination of the maximum dry density and optimum moisture content of laboratory mixed cementitiously stabilized materials SANS 3001-GR40 Determination of the California bearing ratio SANS 3001-GR50 Preparation, compaction and curing of specimens of laboratory mixed cementitiously stabilized materials 4

5 11 SANS 3001-GR51 Sampling, preparation, compaction and curing of field mixed freshly cementitiously stabilized materials including the determination of the MMD and OMC Revisions SANS 3001-GR52 Sampling and preparation of cored specimens of field compacted, matured, cementitiously stabilized material SANS 3001-GR53 Determination of the unconfined compressive strength of compacted and cured specimens of cementitiously stabilized materials SANS 3001-GR54 Determination of the indirect tensile strength of compacted and cured specimens of cementitiously stabilized materials TMH1 A1(a) & A5 SANS 3001 GR1 Description Apparatus Sample Procedure Comments Wet sieve & prep of fines A1 (b) GR2 Dry sieve Sieve sizes rationalised Sieve sizes rationalised Similar Similar Similar, with <0,075 Sieve sizes incorporate e.g. 4,75 to 5 d Dry only < 5 mm sieve to 0,425 mm 0,075 mm fraction not determined 5

6 TMH1 A2 & A3 A2 & A3 SANS 3001 GR10 GR11 Description Apparatus Sample Procedure Comments Atterberg limits & LS LL only refers to GR10 for PL & LS Similar Similar One point LL, PL and LS Similar Similar Two point LL only Flow curve LL only Instead of describing mc method in each test method provides generic for all situations A2 & A3 GR12 Similar Similar - GR20 Moisture content Reintroduce s LS from old TMH1 : Method same but splitting up LL methods New TMH1 A7 A8 SANS 3001 GR30 GR40 Description Apparatus Sample Procedure Comments Maximum dry density Californian Bearing Ratio Similar Similar Allows for scalped >37,5 (ref) or crushed <20 Scalped >37,5 Similar with greater detail of mc points Similar C effort 5 layers x 11 blows Differs in sample prep of >20 mm Differs in sample prep of >20 mm 6

7 Most methods are very similar to traditional TMH1 with minor changes & amendments. The Moisture determination is intending for use throughout the SANS 3001 methods. Minor amendments made to rationalise apparatus dimensions such as mould sizes. Changes to some sieve sizes appears to be significant but all are less than 7 % does not affect outcome as they are given a slightly altered position on the grading curve. GRADING Nominal aperture size of sieve (mm) Percentage passing through sieve by mass Nominal max size 37,5 mm 26,5 mm 37, , , , , ,

8 Sieve size (mm) Maximum nominal size (mm) Semi-gap Continuously graded 37,5 26,5 37,5 26,5 Percentage passing sieve by mass 37, , , , , , , , , , , , , MDD difference primarily due to scalping of +37,5 mm fraction as reference method for preparing sample procedure for crushing coarse material to pass +20 mm fraction also given with restrictions CBR is different in that reference sample preparation (scalping) used in GR30 is used the compaction effort for the C specimen is 5 layers x 11 blows instead of 3 layers x 55 blows. 8

9 Apparatus dimensions critical to outcome of method or procedure are given a tolerance All other dimensions nominal & should be considered fit for purpose. Existing apparatus that complies with the requirements of TMH1 may be used until apparatus no longer fit for purpose. More detail descriptions provided in test methods to ensure reduced variance Not much different but ensures all conduct test method correctly Ensure steps are made more explicit Additions or revisions Larger particles 14 mm may be re-orientated by hand to assist in getting them to pass thru the sieve openings without any additional force. Hand sieving still reference method. Mechanical sieving allowed but each sieve verified by hand sieving No over loading allowed on individual sieves. Table detailing maximum mass per sieve size allowed. Sieving completed when > 0.1% of total sample mass passes thru sieve after 1 minute of continual sieving. Total mass difference before & after sieving < 1.0%. Method also covers maintenance & traceability of sieves. 9

10 Natural Crushed gravels Concrete, surface treatments, HMA 63, (53,0) 50 (53) 37, (26,5) 25 (26.5) 20 (19,0) 20 (19) 14 (13,2) 14 (13.2) 10 (9.5) 7.1 (6.7) 5 (4,75) 5 (4.75) 2,0 2 (2.36) 1 (1.18) 0.6 0,425 < 0, < < Combines TMH1 method A5 ( mm) Constant mass = < 0.1 % change in mass over 1 hr drying Scale size dropped from 5 4kg accurate to 0,1 g If fraction to be tested use 450 g Amount of material required detailed Full fraction > 20 mm weighed. Fraction of material used in test used to reduce fraction > 20 mm in same proportion Material not quartered 10

11 Although GR also applicable to AG. Do not use microwave ovens. Separated into field & lab samples + large (> 50 g) & small (< 50 g) samples. Genuine dry grading used for production control in quarries for Crushing QC/QA No wetting agent required for fines Scales increased to 20 kg from 5 kg Sample size detailed Brush fines from coarse aggregate Other changes for wet sieving also apply 11

12 Combines all 3 test methods LL, PL & LS Uses 1 point test for experienced testers GR11 & GR12 give instruction for 2 point & flow curve method for less experienced testers Either on or & mm For high PI s (> 20) use flow curve LS trough also baseless for highly plastic material (PI > 20) Material increased from 48 approx 60 g PL 2 determinations of 2 samples each 4 samples in 2 tins of 2 3 g each Apparatus dim changes Moulds 152 ± 0.5 mm dia, ±1.0 mm for height (152.4 mm) Collar at least 70 mm Due to wear volume needs to be accurately determined!! Spacer plate 25 ± 1.0 mm (25.4 mm) Concrete 25 MPa 750 x 750 mm (200 kg) Hammer 50 mm diameter, g (4 536 g) fall 460 mm (457.2 mm) Mass loss 20 g recondition or replace) 12

13 Drying process given in more detail Aggregates scalped on 37.5 mm sieve If < 30 % retained on 20 mm sieve Conduct crushing as per TMH 1 method Sample size > to 40 kg, CBR 65 kg 16 split riffled fractions combined in specific manner Soaking once moistened limited to 60 min Moisture determination on half sample once extruded Apparatus dim changes Piston mm 2 (1935 mm 2 ) Penetration rate 1 mm/ min (1.27 mm/min) Depth to 2.5 mm (2.54), 5.0 mm (5.08), 7.5 mm (7.62) penetration piston head 50 ± ± 50 g B mould 22 blows on 5 layers (25 blows on 5 layers) C mould 11 blows on 5 layers (55 blows on 3 layers) Water height in bath approx 10 mm (12 mm) Penetration & force read every 30 ± 2 sec (0.635 mm) 13

NOTES TO THE SPECIFICATION FOR REPEATED LOAD TRIAXIAL (RLT) TESTING FOR PAVEMENT MATERIALS

NOTES TO THE SPECIFICATION FOR REPEATED LOAD TRIAXIAL (RLT) TESTING FOR PAVEMENT MATERIALS 1. SCOPE This specification details the 6 stage permanent strain Repeated Load Triaxial (RLT) test. The RLT test