Your SlideShare is downloading. ×
20320130406006 2-3
20320130406006 2-3
20320130406006 2-3
20320130406006 2-3
20320130406006 2-3
20320130406006 2-3
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

20320130406006 2-3

176

Published on

0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
176
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
4
Comments
0
Likes
0
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. International Journal of Civil Engineering and CIVIL ENGINEERING AND6308 INTERNATIONAL JOURNAL OF Technology (IJCIET), ISSN 0976 – (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME TECHNOLOGY (IJCIET) ISSN 0976 – 6308 (Print) ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December, pp. 55-60 © IAEME: www.iaeme.com/ijciet.asp Journal Impact Factor (2013): 5.3277 (Calculated by GISI) www.jifactor.com IJCIET ©IAEME A COMPARATIVE INVESTIGATION ON LABORATORY WHEEL TRACKING WITH MEDIUM SCALE ACCELERATED TESTING Dr. K.V.KRISHNA REDDY Professor, Civil Engineering Department, MVSR Engineering College, Hyderabad, AP, India ABSTRACT In the present study, an attempt is made to compare the rut resistance results obtained from Laboratory wheel tracking Equipment with that of the field testing using a Medium Scale Accelerated Pavement Rut Tester. The study includes evaluation of the conventional and modified bituminous surface courses in the laboratory and field testing with Medium Scale Accelerated Pavement Rut Tester (MAPRT) on a test track. Modification of the bituminous concrete is done with fly ash and lime. The results showed that the laboratory wheel tracking results are conservative by 50%. Key Words: Medium Scale Accelerated Pavement Testing, Laboratory Wheel tracking, Rutting 1. INTRODUCTION In recent years, highways have experienced an increase in rutting in bituminous concrete pavements. The increased rutting has been attributed to increase in axle loads and traffic volumes. The base course and Subbase materials used in the conventional flexible pavements have good material properties and sufficient strength to transfer the loads coming from the top layers leaving the surface course vulnerable to damages. The performance of the top surface material is evaluated by either laboratory wheel tracking device, medium scale accelerated testing or full scale testing. Full scale testing need long study periods leaving the option between laboratory and medium scale testing. In the present study, an attempt is made to compare the results of rutting resistance of the bituminous concrete mixes with a laboratory wheel tracking device and a medium scale accelerate pavement rut tester (Krishna Reddy.K.V, 2007). Conventional bituminous concrete along with filler modified bituminous concrete is considered for evaluating the comparison. 55
  • 2. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME 2. RESEARCH METHODOLOGY 2.1 Laboratory testing 80/100-penetration grade bitumen has been considered as basic material for the surface course. Aggregates with grade II specifications as per MORTH (Ministry of Road Transport and Highways) specification have been collected from local quarry. Basic material properties have been determined as per codal provisions. Laboratory tests, namely abrasion, attrition, impact value, shape and crushing value have been conducted on the aggregate and the properties of the same are reported in Table 1. Tests on bitumen, namely penetration, ductility, softening point, specific gravity and flash& fire point test have been conducted and the findings are as per Table 2. Table 1 Properties of aggregate used for surface course Property Value Property CA 2.79 Specific gravity Abrasion value FA 2.76 15% Impact value Attrition value 20% Crushing value Shape test (EI+FI) Table 2 Properties of bitumen used for modification Property Value Property 1.04 Specific gravity Ductility Penetration (in 0.1mm) Softening point 84.65 Flash point Fire point 0 47 C Value 24% 21% 13% Value 100+ cm 2700C 3150C 130 Sec Viscosity Fly ash is procured from Ramagundam thermal power plant, Hydrated lime of specific gravity 2.35 is procured locally. Filler is introduced by replacing the finer fraction (<75micron) in the aggregate in terms of % by weight of aggregate. Marshall Mix design using conventional materials was conducted on three samples each. The optimum bitumen content for conventional bituminous concrete mix is found to 4.3% for grade-II aggregates. Further, optimum filler content in case of lime and fly ash were evaluated by adding them at the optimum bitumen content for the conventional bitumen The mix design values for conventional and modified mixes are as given in Table 3. S.No Table 3. Properties of conventional and modified bituminous mixes Fly ash Lime modified Mix / Property Conventional mix modified mix mix 1 Optimum Bitumen / filler content 2 4.3% (Bitumen) 2.30% 2.80% MSV (Kg) 1300 1505 2650 3 Air voids (%) 3.875 4.5 4.05 4 Flow value (mm) 2.375 3.38 3.5 5 Bulk density (g/cc) 2.520 2.43 2.446 56
  • 3. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME 2.2 Equipment used Laboratory wheel tracking test (hamburg) was used in the laboratory to evaluate the rutting resistance of the conventional and filler modified bituminous concrete samples. Medium Scale Accelerated Pavement Rut Tester (MAPRT) is used to conduct field tests operating on a circular track. This equipment can be used to evaluate the performance of the pavements in terms of rut depth. The lab and field equipments used are as shown in the Fig. 1(a) and (b). Fig.1 (a) Laboratory wheel-tracking test Fig.1 (b) Medium scale accelerated pavement rut tester 2.3 Test Track Layout and Design The test track pavement lay out is as shown in Fig.2. Design of the test track was done to ensure that the stresses reach the subgrade. FPAVE program was used to determine the stresses reaching the subgrade. Since, the wheel considered distributes load over a circular area of radius 2.82cm, to ensure that the stresses reach the subgrade and facilitate the testing of subgrade and surface in combination, a pavement with 40mm thick bituminous concrete, 75mm of WBM base course and 100 mm of subbase course was prepared. This pavement system is similar to the fullscale pavements in terms of stresses reaching the subgrade under full-scale wheel loads. 57
  • 4. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME 3 DATA ANALYSIS The results obtained are plotted with number of wheel load repetitions on x -axis and rut depth on y-axis as shown in Figure 3. for both laboratory wheel tracking testing and test track testing using medium scale accelerated pavement rut tester. Fig.2 Test track Layout Fig 3. Plot showing rut life of the bituminous mixes in terms of wheel load repetitions 58
  • 5. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME 4. RESULTS The plots are interpreted and the results are tabulated in the Table 4. It depicts the no of wheel load repetitions sustained by the conventional and filler modified bituminous concrete materials under the laboratory wheel tracking test on laboratory samples and under medium scale accelerated pavement rut tester on the test track. Table 2 Rut Life of pavement in terms of repetitions of wheel load S. No 1 2 3 Type of Bituminous Surface Conventional Flyash modified Lime modified No of repetitions for a rut depth of 25.4mm Wheel tracking test 190000 225000 240000 Medium Scale Accelerated Pavement Rut Tester 132000 152027 160000 % Variation 43.9% 48% 50% 5. ACKNOWLEDGEMENT At the outset the author would thank the Head, CED and TE division, and Head CED, MVSREC for their valuable guidance and encouragement during experimentation. 6. CONCLUSION 1) Conventional bituminous concrete could sustain 190000 wheel load repetitions in the Laboratory compared to 132000 repetitions on field under medium scale accelerated testing. 2) Bituminous concrete modified by 2.8% Hydraulic lime could sustain 225000 wheel load repetitions in the Laboratory compared to 152027 repetitions on field under medium scale accelerated testing. 3) Bituminous concrete modified by 2.3% flyash could sustain 240000 wheel load repetitions in the Laboratory compared to 160000 repetitions on field under medium scale accelerated testing. 4) The laboratory wheel tracking results are conservative by 50% when compared to accelerated pavement testing results using a medium scale accelerated pavement rut tester. 7. REFERENCES 1. 2. 3. Aschenbrener, T., R. Terrel, and R. Zamora. (1994), “Comparison of the Hamburg WheelTracking Device and the Environmental Conditioning System to Pavements of known Stripping Performance” Rep.No.CDOT-DTD-R-94-1, Colorado Department of Transportation, Denver, CO. Aschenbrener, T. (1994), “Comparison of Test Results From Laboratory and Field Compacted Samples - Final Report” Rep. No. CDOT-DTD-R-94-3, Colorado Department of Transportation, Denver, CO Carl W. Lubold, Jr. (2001), “Are u in a Rut?”, Pro. Moving forward, The Pennsylvania Local Road Program, Pennsylvania, Vol. 19, No.2, pp4-5. 59
  • 6. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. Cockrell, C. F. and Leonard, J. W., (1970), “Characterization and Utilization Studies of Limestone Modified Flyash”, Coal Research Bureau, Vol. 60. Dr. K.V.Krishna Reddy, “Benefit Analysis of Subgrade and Surface Improvements in Flexible Pavements”, International Journal of Civil Engineering & Technology (IJCIET), Volume 4, Issue 2, 2013, pp. 385 - 392, ISSN Print: 0976 – 6308, ISSN Online: 0976 – 6316. Collins, R. J., and Ciesielski, S. K. (1992), “Highway Construction use of wastes and Byproducts” Utilization of Waste Materials in Civil Engineering Construction, Published by ASCE, New York, pp.140-152 Dr. K.V.Krishna Reddy, “Influence of Subgrade Condition on Rutting in Flexible Pavementsan Experimental Investigation”, International Journal of Civil Engineering & Technology (IJCIET), Volume 4, Issue 3, 2013, pp. 30 - 37, ISSN Print: 0976 – 6308, ISSN Online: 0976 – 6316. Durga Prasad, K. (2002), “A study of lime and flyash on the performance of bituminous concrete mix”, Mtech thesis, NITW. FPAVE, “Software program for Analysis and Design of Flexible Pavements”, Transportation Engineering Section, Civil Engineering Department, IIT, Kharagpur. MORT&H - 2001: Specifications for Roads and Bridge works, Ministry of Road Transportation and Highways. Dr. K.V.Krishna Reddy and Mr.K.P.Reddy, “Maturity Period and Curing as Important Quality Control Parameters for Lime Stabilized Clay Subgrades”, International Journal of Civil Engineering & Technology (IJCIET), Volume 4, Issue 2, 2013, pp. 393 - 401, ISSN Print: 0976 – 6308, ISSN Online: 0976 – 6316. Krishna Reddy,KV, 2007, “Medium Scale Accelerated Pavement Rut Tester”, Indian Highways, Indian Roads Congress, New Delhi, Vol 35, No.12, PP 23-30 Metcalf, J. B. (1996), “Application of Full-Scale Accelerated Pavement Testing”, NCHRP Synthesis of Highway Practice, Rep. No. 235, National Research Council, TRB, Washington D.C. Dr. K.V.Krishna Reddy, “Rutting Resistance of Filler Modified Bituminous Concrete Surfaces”, International Journal of Civil Engineering & Technology (IJCIET), Volume 4, Issue 2, 2013, pp. 250 - 257, ISSN Print: 0976 – 6308, ISSN Online: 0976 – 6316. Romero, P., and Stuart, K. (1998), “Evaluating Accelerated Rut Testers”, Public Roads Journal, Vol. 62, No. 1, pp 50-54. Williams, R.C., and Prowell, B.D. (1999), “Comparison of Laboratory Wheel-Tracking Test Results with WesTrack Performance” TRR-1681, TRB, pp 121-128. Yoder, EJ and Witczac, M.W (1975), “Principles of Pavement Design”, 2nd Edition, John Wiley & Sons. Dr. K.V.Krishna Reddy, “Stabilization of Medium Plastic Clays using Industrial Wastes”, International Journal of Civil Engineering & Technology (IJCIET), Volume 4, Issue 3, 2013, pp. 38 - 44, ISSN Print: 0976 – 6308, ISSN Online: 0976 – 6316. 60

×