CT4860 STRUCTURAL DESIGN OF PAVEMENTS

More documents

Recommendations

Info

5.4.4. Substructure 85 5.4.5. Concrete 86 5.4.6. Traffic load stresses 86 5.4.7. Temperature gradient stresses 87 5.4.8. Thickness plain/reinforced concrete pavement 89 5.4.9. Additional checks plain concrete pavements 90 5.4.10. Determination of the reinforcement of reinforced concrete pavements 92 5.4.11. Additional checks reinforced concrete pavements 100 5.5. Influencing factors 100 6. REFERENCES 102 2
1. INTRODUCTION In many countries concrete pavement structures are becoming increasingly popular due to competitive investment costs and lower maintenance costs (in comparison with asphalt pavements) and due to an increasing confidence in a good long term pavement behaviour (caused by more reliable design methods and better construction techniques). This lecture note intends to explain the principles of the structural design of the two most widely applied types of concrete pavement, which are plain (unreinforced) concrete pavements and continuously reinforced concrete pavements. In chapter 2 the materials usually applied in the various layers of (un)reinforced concrete pavements are described in general terms. Furthermore (indicative) values for the most important material properties are given. Chapter 3 explains the usually applied theories for the calculation of the flexural tensile stresses (and the vertical displacements) within the concrete top layer due to the most important (external) loadings. These are not only the traffic loadings but also the temperature gradients and unequal subgrade settlements. Next the principles of the fatigue analysis, to take into account the repeated traffic loadings together with the temperature gradient loadings, are discussed. Furthermore the applicability of the finite element method with respect to the structural design of concrete pavements is reviewed in general terms. In chapter 4 first some existing empirical concrete pavement design methods and the flowchart of some analytical design methods are briefly described, and a critical review about the applicability of these two types of design method is presented. Finally, in chapter 5 the Dutch analytical structural design method for concrete pavements is discussed. The original method (developed in the eighties) as well as the (in the nineties) revised method, both only valid for plain concrete pavements, are briefly discussed. Emphasis is laid on the current method, released early 2005 as the software program VENCON2.0, that covers both plain and reinforced concrete pavements. 3
Page 1: CT4860 STRUCTURAL DESIGN OF PAVEMEN
Page 5: Table of Contents 1. INTRODUCTION 3
Page 9 and 10: main part of the traffic loading. T
Page 11 and 12: Well graded crusher run, (high qual
Page 13 and 14: Property Sandcement Lean concrete A
Page 15 and 16: In the Dutch design method for conc
Page 17 and 18: 2.6 Layout of concrete pavement str
Page 19 and 20: widened (e.g. to 8 mm) to a certain
Page 21 and 22: The pavement was constructed in two
Page 23 and 24: p = ground pressure (N/mm 2 ) on to
Page 25 and 26: Lightweight fill material Density (
Page 27 and 28: Example Sand subgrade: ko = 0.045 N
Page 29 and 30: Figure 10. Mean distribution (%) of
Page 31 and 32: 2. Directly besides the central par
Page 33 and 34: where: h = thickness (mm) of the co
Page 35 and 36: Positive temperature gradient ∆t
Page 37 and 38: There exist a lot of (modified) Wes
Page 39 and 40: P = 50 kN = 50000 N p = 0.7 N/mm²
Page 41 and 42: Figure 15. Influence chart of Picke
Page 43 and 44: Figure 17. Influence chart of Picke
Page 45 and 46: 2 Ed I d S d = (36) 2 3 1 + ( 1 +
Page 47 and 48: slab wu = deflection (mm) at the jo
Page 49 and 50: Example L = 4.5 m = 4500 mm k = 0.1
Page 51 and 52: Figure 22. Factor F as a function o
Page 53 and 54: Example In this section an example
Page 55 and 56: Table 10 clearly shows that in the
Page 57 and 58:
For instance, on the basis of numer
Page 59 and 60:
Although the increase of the flexur
Page 61 and 62:
4. DESIGN METHODS FOR CONCRETE PAVE
Page 63 and 64:
Figure 28. AASHTO design chart for
Page 65 and 66:
4.2.3 The BDS-method The British de
Page 67 and 68:
Figure 32. Additional plain concret
Page 69 and 70:
of the concrete layer. Figure 34 sh
Page 71 and 72:
where: nij = predicted number of re
Page 73 and 74:
5. DUTCH DESIGN METHOD FOR CONCRETE
Page 75 and 76:
Only the technical aspects of the o
Page 77 and 78:
2 ' ⎛ ⎞ L σ = 0.85 σ”t = 0.
Page 79 and 80:
5.3 Revised design method In the ea
Page 81 and 82:
Therefore in the revised method the
Page 83 and 84:
The tensile flexural stress at the
Page 85 and 86:
w l = 4.8 e -0.35.log Neq (74) The
Page 87 and 88:
Axle load group (kN) Number of carr
Page 89 and 90:
5.4.3 Climate In the years 2000 and
Page 91 and 92:
- W according to equation 81a at pr
Page 93 and 94:
5.4.8 Thickness plain/reinforced co
Page 95 and 96:
W = load transfer at longitudinal e
Page 97 and 98:
‘reference temperature’ at the
Page 99 and 100:
The central tensile force N in the
Page 101 and 102:
σs,cr = tensile stress in reinforc
Page 103 and 104:
In the Dutch design method for conc
Page 105 and 106:
10% 5% reference 5% 10% smaller sma
Page 107 and 108:
13. Houben, L.J.M. Finite element a
Page 109 and 110:
31. Guide for the Standardisation o
show all

CT4860 STRUCTURAL DESIGN OF PAVEMENTS

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?