Journal of Research in Engineering and Applied Sciences

JREAS, Vol. 2, Issue 01, Jan. 201729

FATIGUE DATA ANALYSIS OF UTWT PAVEMENTUSING FIBRE REINFORCED CONCRETE

1,2Student, B.E. Final Year, Department of Civil Engineering,3Assistant Professor, Department of Civil Engineering,

Prof Ram Meghe College of Engineering and Management, Badnera-Amravati, Maharashtra, India1 2 3Email: { sagarits1996@gmail.com, ankushmalviya1@gmail.com, ferozoft@gmail.com}

Abstract

In this paper present the evaluation of Ultra-Thin White Topping using Fibre Reinforced Concrete as an overlaying concrete mix. In India, generally PCC and High Strength Concrete is used at various UTWT sites. In this paper, particular calculation for fatigue data for medium traffic road is carried out. In most of the UTWT pavement it is observed that the common failure type is cracking in pavement. The concrete is a brittle material and it early subjected to cracking. Polypropylene Fibre reinforced concrete is increase the flexural strength of pavement due to which the pavement failure due to cracking is reduced. This paper particularly highlights on Fatigue data by replacing the PCC with PPFRC (polypropylene fibre). These fibre concrete and their mix proportion are design according to IRC-44 guidelines for concrete mix design of rigid pavement. The M40 grade FRC is used for the calculation of fatigue data. Fatigue data is calculated as per IRC SP-76-2008 for medium traffic condition.

Key Words : UTWT, FRC, fatigue data, rigid pavement, flexural strength, PPFRC

1. Introduction

Ultra Thin White Topping is a concrete overlay on distress asphalt pavement for the rehabilitation. Thickness of UTWT varies from 50-100 mm. Most of the time thickness more than 75 mm is adopted for fatigue analysis. In India, most of the pavements are rehabilitate using UTWT pavement at Pune, Mumbai, Thane and Hyderabad. In which most of these projects are using high strength concrete and plain cement concrete. The most predominant failure occur in UTWT pavement is failure due to cracking in edge on corner region. In many pavements, it is found that the pavements are subjected to cracking in central part, these cracking’s generally caused due to the impact of heavy load and less flexural Strength of pavement. In FRC using polypropylene fibre the flexural strength of concrete is increases upto 30-40%. Also, this concrete is providing more stability to pavement against the cracking in edge and corner region. FRC is useful in reduction of warping stresses in UTWT pavements.

The UTWT pavements with PPFRC it gives the more life and better surface quality than other concrete material. The polypropylene fibre increases the flexural strength of UTWT pavement. The PPFRC the amount of bleeding is more with minimum w/c ratio, helps in improving the workability gives smooth finishing for UTWT pavements.

In this paper the fatigue data is collected for pavement using PPFRC as an overlaying concrete having thickness 100 mm. Polypropylene fibre of class is used in concrete for delaying the cracking time. Generally, the polymeric

1 2 3Sagar P. Gawande , Ankush R. Malviya and Feroz H. khan

or polypropylene fibres used because the UTWT pavement required join cutting upto 1/3 of total thickness of UTWT.

The concrete mix is designed according to IRC-44 and evaluation of pavements for fatigue data as per IRC: SP-76.

2. Effect of PPFRC on UTWT pavement

The plain concrete is weak in tension because of presence of micro cracks in it. These micro cracks are also responsible to early failure of pavement. The reduction of these micro cracks achieved by using polypropylene fibre. The figure shows the cracking of pavement under behaviour of failure of pavement with and without polypropylene fibre.

The plain concrete structure cracks into two pieces or break down when the structure is subjected to the ultimate tensile load and cannot carry further load or deformation beyond.

Figure 1: Effect of PPFRC on UTWT pavement

The PPFRC structure cracks at the peak tensile load, but does not break into pieces the and can maintain a load to very large deformations.

The fibres are fill the void and micro crack for improving ductility of UTWT pavement. Also, the uniform bleeding which improve the workability and proper finish to UTWT pavement is achieved.

Important factor governing to Polypropylene fibre is it increases the bond between material and also improves the flexural strength. Polypropylene fibers are gaining popularity because of it is more resistant of corrosion and it is cheap also. PPFRC is a suitable material used in UTWT pavement and it consist the additional strength in flexural fatigue and more resistance to impact etc.

In PPFRC, thousands of small polypropylene fibers are dispersed and distributed throughout randomly in the concrete during mixing, and due to random distribution, it improves concrete properties in all directions of pavement.

3. Materials Specifications

3.1 Cement :

Ordinary Portland Cement (OPC) of grade 53 (fly ash based) used for the mix design calculation.

3.2 Aggregate :

Locally available sand from river is used as fine aggregate of maximum size 4.75 mm down size and crushed quartzite aggregate with a maximum size of aggregate of 20mm down size, used as a coarse aggregate.

3.3 Water :

free from impurities and dust, clear potable water is used in concrete.

3.4 Fiber :

The macro synthetic polypropylene fibers were having a length of 50mm and having average thickness 1mm, having an aspect ratio of 50.

3.5 Admixture :

Water reducing admixture is used to improve workability at min W/C ratio.

4. Mix Design according to IRC 44-2008

The concrete mix is design for pavement for M40 grade and using 1% polypropylene fiber by volume of concrete.

(a) Grade designation M40 (b) Type of cement OPC 53 grade

(fly ash based) (c)

Maximum nominal size of

aggregate used in mix

20mm

(d)

Minimum cement content 325 kg/m3

(e)

Maximum water -cement

ratio

0.40

(f)

Workability

20 ±5 mm (slump

value)

(g)

Degree of supervision

Good

(h)

Type of aggregate

Crushed angular agg.

(i)

(j)

(k)

Maximum cement content

chemical admixture

Fibre

425 kg/m3

Superplasticizer

(to reduce

the amount of water

required)

Polypropylene Fibre of

size (1 mm thick, 50 mm

long)

Mix proportion

The concrete mix design is carried out according to IRC 44 and the proportion of Cement: FA: CA is calculated as 1:2.21:2.98 for W/C ratio of 0.33, chemical admixture used as 1% of weight of cementious material. 1% polypropylene fibre is also added in concrete mix [9].

Table 1: Mix proportion of ingredient of PPFRC

Ingredient Weight /m3

Cement 370 kg

Water 165 lit.

Fine aggregate 818.7 kg

Coarse aggregate 1105.9 kg

Chemical admixture 3.0 kg

Water cement Ratio 0.33

Fibre

3.7 kg

5. Design of UTWT pavement

The design of UTWT pavement carried out according to guidelines given in IRC SP 76-2008. following steps considered for design of UTWT pavement.

5.1 Design Steps :

The thickness of UTWT pavement has been designed according to the IRC: SP-76:2008 “Tentative guidelines for conventional, thin and ultra- thin whitetopping”

30 JREAS, Vol. 2, Issue 01, Jan. 2017

JREAS, Vol. 2, Issue 01, Jan. 2017

5.1.1 Find traffic in terms of commercial vehicles per day (cvpd)

Design traffic in terms of Cumulative repetition (C) is calculated by using formula given below(1) [7]-

Traffic data is collected for 4 days and average traffic (A)= 240 commercial vehicles per day (cvpd).

Growth rate (r) = 2.5%

Design period is assumed as 20 years (n).

Cumulative repetition (C)= 5954860

25% of Cumulative repetition as design traffic

Design traffic=1488715 Vehicles

n(365×A{(1+r) -1})

rC = (1)

5.1.2 Evaluate k value of subgrade

The modulus of subgrade reaction (k-value) has been determined has been conducting Benkelman Beam Deflection (BBD) on the surface of Hot Mix Asphalt (HMA) [7].

By correlating the maximum value of deflection of HMA pavement obtained from BBD test the k-value has been determined from the graph shown in figure 2.

Deflection obtained from BBD = 1.18 mm

Modulus of subgrade reaction (k)= 10.04 (Kg /cm2 /cm)

31

5.1.7 Determination of stress ratio

N= Fatigue Life

SR= Stress ratio = 0.47

The repitation of 6 tonnes and 9 tonnes vehicle is1488715

Vehicles. Percentage of different Axel load assumed as given in tables 3. The fatigue life and Fatigue consumed by pavement is given in Table in 4 and Table 5 respectively.

2

6. Determine fatigue life consumed

Table 3: Percentage of axel load for the design of UTWT

Table 4: Design from Fatigue consideration (single axle) and stress ratio at different axle load

Table 5: Design from Fatigue consideration (Tandem axle) and stress ratio at different axle load

As vehicle moving on road repeatedly the fatigue damage of concrete pavement takes place. this fatigue damage may lead to increase in flexural stress in pavement.

Due to flexural stress micro Cracks are formed in concrete may leads to failure of pavement. for design of cement concrete layer is 100 mm. The total fatigue life consumed is 38%, which is less than 100 %; therefore, design is safe from fatigue life consideration. Hence, final thickness of PPFRC to be adopted is 100 mm for UTWT pavement.

7. Summary of design of UTWT pavement

The following table shows the values of various terms are calculated in design step and fatigue life consumed step. Also, it Shows the various parameter derived from IRC 58-2002.

Table 6: Summary of Design of UTWT pavement using PPFRC

32 JREAS, Vol. 2, Issue 01, Jan. 2017

8. Conclusions

The UTWT is a new and emerging pavement rehabilitation technique in which concrete overlay is provided on top of distress pavement.

By using polypropylene fibre, the flexural strength of M40 concrete is calculated by conducting third point load test as 59.50 kg/cm2.

For UTWT pavement the square panel of size 1m x 1m has been provided.

The stress ratio for 100 mm thick UTWT pavement is 0.47

The fatigue life N for stress ratio 0.47 is 3901855.

Fatigue consumed by pavement due to repitation of vehicles is 38 % less than 100 %.

As Fatigue Life consumed by UTWT pavement is less than 100 % the pavement is safe throughout des ign per iod and use of polypropylene fibre reduce the cracking in UTWT pavement.

References

[1] McGhee, K.H., NCHRP Synthesis of Highway practice 204: Portland cement concrete resurfacing, Transportation Research Board, National Research Council, Washington, D.C.,1994, pp.73-82.

[2] American Concrete Pavement Association, Whitetopping – state of practice, ACPA Publication EB210P, Skokie, Illinois, 1998.

[3] Westergaard H. M., “Computation of stresses in concrete roads”. Proceeding of the Highway Research Board, Vol.5, Part I, National Research Council, Washington, D.C, 1926, pp 90-112.

[4] D. R. Jundhare, K.C. Khare, and R.K. Jain, “Ultra-Thin White topping in India: State-of- Practice” by ACEE Int. J. on Transportation and Urban Development, Vol. 2, No. 1, April 2012

[5] Lee, M.K., and Barr, B.I.G. (2004). An Overview of the Fatigue Behavior of Plain and Fibre Reinforced Concrete, Cement and Concrete Composites, Vol. 26, 299-305.

[6] N. Banthia and R. Gupta, “Influence of Polypropylene fiber geometry on plastic shrinkage cracking in concrete,” Cement and concrete research, vol36, pp1263-67, 2006

[7] IRC: SP: 76 – 2008 “Tentative guidelines for conventional, thin and ultra- thin whitetopping”, Indian Road Congress, New Delhi, 2008.

[8] IRC: 58 – 2002 “Guidelines for the design of rigid pavement for highways,” Indian Road Congress, New Delhi, 2002.

[9] IRC: 44 – 2008 “Guidelines for Cement Concrete Mix Design for pavements,” Indian Road Congress, New Delhi, 2008.

33 JREAS, Vol. 2, Issue 01, Jan. 2017