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Table 3.5. Shear capacities for different levels of misalignment.
Longitudinal Translation Vertical Translation Vertical Tilt Dowel Diameter
Embedment, Shear Concrete Shear Rotation, Shear Diameter, Shear
in. Capacity, lbs. Cover, in. Capacity, lbs. in./18 in. Capacity, lbs. in. Capacity, lbs.
2 4900 3.25 10400 0 10400 1.0 5600
3 6600 4.25 12000 0.5 10300 1.125 6800
4 8000 5.25 13400 1.0 10200 1.25 8000
5 9100 7.25 14600 1.5 10300 1.375 9200
6 9900 2.0 9700 1.5 10400
9 10400
causing failure in the laboratory (see Figure 2.13). Therefore, · Case 1: All dowels rotated by the same amount, but adjacent
the ultimate shear forces for dowel misalignments that could dowels are rotated in opposite directions.
not be investigated in the laboratory can be estimated analyt- · Case 2: Each dowel tilted with the same magnitude and in
ically as the shear force corresponding to 0.05 in. [1.3 mm]. the same direction.
Table 3.5 gives the ultimate shear capacities for different · Case 3: The dowel in the wheel path aligned properly, and
levels of longitudinal translation, concrete covers, vertical tilt, each other dowel rotated with the same magnitude and
and dowel diameter. The table shows that the shear capacity of direction.
a dowel is reduced by increasing levels of longitudinal transla- · Case 4: The dowel at the wheel path rotated, and each other
tion (reduced embedment length), increased by increasing dowel aligned properly.
concrete cover, and not affected by the magnitude of vertical tilt.
These results are similar to those observed from the laboratory For each case, joint LTE was calculated as the ratio of the
tests except for the case of 4 per 18 in. [102 per 457 mm] tilt. corner deflection of the unloaded slab to the corner deflection
It also should be noted that the beam test does not account for of the loaded slab. Table 3.6 shows LTE for these four cases with
the effect of interaction with multiple dowels which could be different levels of dowel rotation. LTE is lower for the oppositely
important for vertical tilt. The data also show that reductions in misaligned dowels especially as the dowel tilt exceeds 1 in.
dowel diameter reduce the shear capacity and shear stiffness. per 18 in. [25 mm per 457 mm]. Thus, although the mean
misalignment level of Case 2 was higher than Case 1 (the
3.3.2 Finite Element Slab Model mean misalignment is zero in Case 1), Case 1 results in a lower
joint LTE. Therefore, the mean misalignment level is required
The laboratory tests indicated that dowel rotations up to for characterizing the translational misalignments, but the
2 in. [51 mm] or less per 18 in. [457 mm] of dowel length did standard deviation of the dowels is required to describe the
not result in significantly different dowel-concrete system
rotational joint misalignment. Table 3.6 also shows that,
responses under loading. A similar trend also was observed
for the same magnitude of dowel tilt, the LTE is lower for
from the analytical simulations. However, previous studies
Case 4 than for Case 3, especially at the higher misalignment
(Khazanovich et al., 2001) have shown that rotations of adja-
levels. Thus, the alignment of the dowel in the wheel path
cent dowels or multiple dowels in a single joint can influence
(critical dowel) has a more significant effect on the LTE than
the behavior of the joint. To investigate this effect, a slab
model with multiple embedded dowels was considered. The the alignment of the other dowels in the joint.
material parameters obtained from the beam model were
used to simulate dowel performance using the slab model for
the following four cases of rotational combinations: 3.4 Pavement Performance Modeling
3.4.1 Faulting
Table 3.6. LTE predictions for various levels
of dowel rotation. The equivalent dowel diameter concept requires the consid-
eration of adjustment factors for each type of misalignment.
LTE, percent
Dowel Tilt, in./18 in. Case 1 Case 2 Case 3 Case 4 The development of such factors is presented in this section.
0.5 84.5 86.0 85.7 84.9
0.75 84.1 85.3 85.3 84.4
1 82.0 83.5 85.1 83.2 3.4.1.1 Embedment Length Adjustment Factor
1.25 81.0 82.9 85.1 -
1.5 79.5 82.1 85.2 82.3 The finite element model was used to obtain the embedment
Average LTE 82.2 84.0 85.3 83.7 length adjustment factor. A series of finite element runs were

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12000 the nominal dowel diameter. Therefore, the adjustment factor
for an embedment length of 5 in. [127 mm] is 1.4/1.5 = 0.933.
10000 Figure 3.13 presents the computed adjustment factor remb for
a range of the embedment lengths Lemb. This relationship can
Ultimate Shear Force, lbs.
8000 be presented by the following equation:
6000 remb = -0.010 Lemb
2
+ 0.167 Lemb + 0.324 (6)
4000 where Lemb is the embedment length in inches.
Equation 6 is applicable for embedment lengths between
2000 2 and 6.9 in. [51 and 175 mm]. An adjustment factor of 1
should be assumed for embedment lengths greater than 6.9 in.
0 [175 mm] and 0 for embedment lengths less than 2 in. [51 mm].
0 2 4 6 8 10 In cases where the embedment length of the dowels varies
Embedment Length, in. along the joint, this procedure will result in a different equiv-
Figure 3.11. Dowel shear capacity versus embedment alent dowel diameter for each dowel in the joint. However,
length for 1.5-in. [38 mm] diameter dowels. because the MEPDG faulting model assumes the same diam-
eter for all dowels, a single equivalent dowel diameter that
accounts for all dowels needs to be estimated.
made. The first series was performed for a 1.5-in. [38-mm] Finite element modeling shows that the LTE of the joint
diameter dowel with embedment lengths varying from 2 to is affected by misalignment of the dowel in the wheel path
9 in. [51 to 229 mm] and for dowel diameters ranging from approximately as much as the combined effect of the same
1.0 to 1.5 in. [25 to 38 mm] with a 9 in. [229 mm] embedment. level of misalignments for all of the other dowels in the joint
Figures 3.11 and 3.12 present the relationships between embed- (see Table 3.6). Therefore, the following procedure should be
ment length and shear capacity and between dowel diameter used for a joint with variable dowel embedment lengths:
and shear capacity, respectively.
By equating the shear capacity of a misaligned dowel with 1. Compute an adjustment factor for each dowel in the joint.
the shear capacity of an aligned dowel of reduced diameter, an 2. Determine the mean adjustment factor for all of the dowels
equivalent reduced dowel diameter could be determined. For in the joint.
example, a 1.5-in. [38-mm] dowel with embedment of 5 in. 3. Determine the mean adjustment factor for the three dowels
[127 mm] has a shear capacity of 9000 lb [40 kN] (Figure 3.14), in the critical wheel path (for example, the right wheel path
which is equivalent to that of a 1.4-in. [36-mm] diameter dowel in the truck lane).
with embedment of 9 in. [229 mm]. The adjustment factor then 4. Use the average of the two values obtained in Steps 2 and
is calculated by dividing the corresponding dowel diameter by 3 as the adjustment factor for the joint.
12,000 1.2
10,000
Ultimate Shear Force, lbs.
Correction Factor (remb)
8,000 0.8
6,000
4,000 0.4
2,000
0 0.0
0.8 0.9 1 1.1 1.2 1.3 1.4 1.5 0 1 2 3 4 5 6 7 8 9
Dowel Diameter, in. Embedment Length, in.
Figure 3.12. Dowel shear capacity for various dowel Figure 3.13. Adjustment factor (remb) versus
diameters (embedment length equal to 9 in. [229 mm]). embedment length.

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26
3.4.1.2 Vertical Translation (Low Concrete Cover) [25 mm] should be expected for concrete thicknesses above
Adjustment Factor 12 in. [305 mm]. Therefore, reduction in shear capacity
should be considered only if the reduction in concrete cover
Laboratory beam testing was conducted only for nonverti-
exceeds the normal variability level, as represented by the
cally translated dowels and dowels with a vertical translation following equation:
of 2 in. [51 mm] (representing concrete covers ranging from
1.25 in. to 3.375 in. [32 mm to 86 mm]). The finite element DSC = [ -153.3(CCref
2
- CC 2 ) + 2503(CCref - CC )] d0 (8
8)
beam model was used to extend the results of the laboratory
tests to concrete covers up to 7.25 in. [184 mm]. Dowels
where
1.25 in. and 1.5 in. [32 mm and 38 mm] in diameter were used
DSC = the change in dowel shear capacity in pounds due
in the analysis for concrete covers of less than 5.25 in. [133 mm],
to reduction in concrete cover beyond normal
and only 1.5-in. [38-mm] diameter dowels were used for con-
variability;
crete covers of 5.25 in. [133 mm] and greater (because 1.5-in. CC = the concrete cover in inches; and
[38-mm] diameter dowels are commonly used in thick pave- CCref = the reference level concrete cover in inches.
ments that result in these large concrete covers). This analysis
produced the following relationship between dowel shear CC and CCref can be computed as follows:
capacity and concrete cover:
CCref = HPCC 2 - d0 2 - 0.5, for H PCC 12 in .
DSC = ( -153.3 CC 2 + 2503 CC ) d0 (7)
CCref = HPCC 2 - d0 2 - 1.0, for H PCC > 12 in . (9)
where CC = HPCC 2 - d0 2 - HPCC 2 - Ddepth
DSC = the dowel shear capacity in lbs;
d0 = the dowel diameter in inches; and where
CC = the concrete cover in inches. HPCC = the designed PCC thickness in inches;
d0 = the designed dowel diameter in inches; and
Figure 3.14 presents the relationship between concrete
Ddepth = the depth of the dowel in inches.
cover and shear capacity for two dowel diameters obtained
from model simulations and the laboratory test data.
However, if the computed CCref > 3.5 d0, then 3.5 d0 should
Figure 3.14 illustrates the reduction in shear capacity due
be used as the CCref. This maximum value was selected based
to a reduction in concrete cover. The field measurements
on the results showing no increase of dowel shear capacity for
conducted in this study showed that vertical translation of
concrete cover exceeding 3.5 times the dowel diameter.
up to 0.5 in. [13 mm] should be expected for concrete thick-
If CC is equal to or greater than the reference concrete
nesses of 12 in. [305 mm] or less, and a study conducted by
cover (CCref), no reduction in effective dowel diameter should
MTO (MTO, 2007) concluded that translation of up to 1 in.
be considered (i.e., rcc = 1.0). If CC is less than 2 in. [51 mm], the
adjustment factor should be considered to equal 0 (i.e., rcc = 0)
because of high spalling potential. Effective dowel diameters
16000
1.5 in. Laboratory should be considered for intermediate values.
1.5 in. ABAQUS Figure 3.15 presents the relationship between dowel diam-
1.25 in. Laboratory
1.25 in. ABAQUS
eter and dowel shear capacity obtained from finite element
12000
1.5 in. Equation 7 analysis for HPCC equal to 8 in. [203 mm]. The relationship
Shear Capacity, lbs.
1.25 in. Equation 7 between the reduction in normalized shear capacity and the
reduction in dowel diameter from d0 to d is presented as
8000
follows:
4000
DSC = 9628 ( d0 - d ) (10)
Thus, the adjustment factor for concrete cover rcc can be pre-
0 sented as follows:
0 1 2 3 4 5 6 7 8
Concrete Cover, in.
d 1 DSC
rcc = = 1- (11)
Figure 3.14. Shear capacity versus concrete cover. d0 9628 d0

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27
12000 diameter. The figure indicates that the adjustment factor
decreases as the vertical translation increases; the decrease
Change in Shear Capacity is less drastic for thicker concrete slabs because of the larger
concrete cover.
Ultimate Shear Force, lbs.
8000
Finite element analysis showed that the LTE near the slab
corner is affected by the dowel in the wheel path as much as
Change in all of the other dowels in the joint combined. Therefore, the
Dowel Diameter
4000 following procedure should be used for a joint with variable
concrete cover:
1. Compute an adjustment factor for each dowel in the joint.
0 2. Determine the mean adjustment factor for all of the dow-
0.9 1 1.1 1.2 1.3 1.4 1.5 1.6
els in the entire joint.
Dowel Diameter, in.
3. Determine the mean adjustment factor for the three dow-
Figure 3.15. Shear capacity versus dowel diameter. els in the critical wheel path (for example, the right wheel
path in the truck lane).
4. Use the average of the two values obtained in Steps 2 and
Substituting Equation 8 into equation 11 results in the 3 as the adjustment factor for the joint.
following adjustment factor for each individual dowel:
3.4.1.3 Rotation (Horizontal or Vertical Tilt)
rcc = 1 - -153.3 (CCref ) + 2503 (CCref ) + 153.3(CC )
2 2
Adjustment Factor
- 2503 (CC ) 9628 (12) Dowel rotation in the form of vertical tilt and horizontal
skew can have adverse effects on the performance of concrete
pavement joints. Increased restraint to joint opening and
However, the adjustment factor should be assumed to
closing due to dowel rotation may cause micro-damage and
be zero for concrete covers less than 2 in. [51 mm] because
minor spalling around dowels (as observed in the laboratory
low concrete cover can cause spalling around the dowel. Even
tests) that reduce joint LTE. Laboratory tests and analyses have
if spalling is not visible, the ability of the dowel to transfer
shown similar effects for vertical tilt and horizontal skew.
the load will be diminished. Figure 3.16 presents the cal-
culated dowel diameter adjustment factors versus vertical Therefore, the equivalent dowel diameter concept can be
translation for combinations of PCC thickness and dowel applied in a similar manner to both types of misalignment.
The equivalent dowel diameter concept used to account for
the effects of translational misalignments also is used to account
for the effects of rotational misalignments. As noted earlier,
1.1
relative rotations of dowels (e.g., opposite misalignment) have
a greater effect on the joint performance than rotational mag-
1
nitude. The effect of rotational misalignments on joint LTE was
determined by analyzing slabs with multiple dowels. In this
0.9
analysis, the corner deflections of the loaded and unloaded
Correction Factor
13 in. thick - 1.5 in. dd slabs were computed for various combinations of dowel
0.8 10 in. thick - 1.5 in. dd
misalignment. The joint LTE was calculated by dividing the
13 in. thick - 1.25 in. dd
10 in. thick - 1.25 in. dd unloaded slab corner deflection by the loaded slab corner
0.7
8 in. thick - 1.25 in. dd deflections, and the nondimensional joint stiffness, JStiff, was
determined using the following equation (Khazanovich and
0.6
Gotlif, 2002):
0.5
-1.17786
-6 -4 -2 0 2 4 6 1
- 0.01
Vertical Translation, in. LTE
JStiff = 0.012 (13)
Figure 3.16. Concrete cover adjustment factors (rcc)
versus vertical translation for combinations of dowel
diameter and PCC thickness. in which LTE is expressed as a percentage.

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Finite element analysis was performed for each of the four 87
rotational misalignment cases described in Section 3.3.2, and 86
the joint stiffness was determined. Linear regression analysis y = 1.0001x
R² = 0.9376
was used to develop the following relationship: 85
Predicted LTE (%)
84
JStiff = JStiff 0 - 0.20623 × MeanTilt - 0.61796 × StDTilt
83
- 0.86862 × WPTilt (14)
82
where
81
MeanTilt = the average tilt of the dowels in the joint in
inches per 18 in.; 80
StDTilt = the standard deviation of the tilt of the dowels
79
in the joint in inches per 18 in.; and 79 80 81 82 83 84 85 86 87
WPTilt = the maximum dowel tilt in the critical wheel Finite Element Model Computed LTE (%)
path in inches per 18 in. Figure 3.17. Computed versus predicted LTEs for
various rotational misalignments.
JStiff0 is the computed stiffness of the joint with aligned
dowels; this value is presented in Table 3.7 for each dowel
diameter. These joint stiffness values account for the contri- Based on these observations, joints with oppositely misaligned
butions of the dowels to the stiffness of the joint, but not dowels with rotation of 0.5 in. per 18 in. [13 mm per 457 mm]
those of aggregate interlock, foundation support, or other dowel length were used to represent the nominal condition.
factors. Thus, any combination of dowel misalignment that results
The joint LTE can be predicted using the following equation in a LTE equal to or greater than the nominal LTE will not
(Crovetti, 1994): affect the pavement performance; rotations that result in
less than the nominal LTE will have adverse effects on the
100%
LTE = (15) joint performance.
1 + 1.2 ( JStiff )
-0.849
Table 3.8 gives the nominal load transfer efficiencies obtained
from the finite element slab model for various dowel diameters;
Figure 3.17 presents the load transfer efficiencies using lower LTE is obtained for smaller dowel diameters. The pre-
Equations 14 and 15 versus the load transfer efficiencies dicted LTE can be expressed in terms of the diameter of a
computed from the finite element analysis. These values properly aligned dowel, using the following relationship:
correlate well.
Figure 3.18 shows the sensitivity of predicted LTE to the d = 0.0103e 0.0582 LTE (16)
level of tilt for uniformly and oppositely tilted 1.25-in. [32-mm]
diameter dowels in a joint. The LTE decreases with increases
in tilt level. The LTE values are lower for oppositely tilted 86
dowels than for uniformly tilted dowels. Similar observations Case 2: Uniformly Tilted
were noted in earlier studies (Khazanovich et al., 2001). 84
The field study showed that construction practices should Case 1: Oppositely Tilted
permit the installation of dowels with tilt no greater than 82
Predicted LTE (%)
0.5 in. per 18 in. [13 mm per 457 mm] of dowel length. Such
a level of misalignment did not affect pavement performance. 80
78
Table 3.7. Computed stiffness for various
76
dowel diameters.
Dowel Diameter (in.) JStiff0 74
1 6.537 0 0.25 0.5 0.75 1 1.25 1.5 1.75 2
1.125 7.447 Tilt, in./18 in.
1.25 8.461
1.375 9.601 Figure 3.18. Predicted LTEs for oppositely and
1.5 10.894 uniformly tilted dowels.

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Table 3.8. LTE versus dowel 40
diameter for slab model Aligned
35
simulations. Misaligned
30
Dowel Diameter, in. LTE
0.75 0.73 25
1 1.01
Stress, psi.
1.125 1.14 20
1.25 1.26
1.375 1.36 15
1.5 1.46
10
5
By substituting Equation 15 into Equation 16, the adjustment
0
factor for rotational misalignment (vertical tilt or horizontal 0 0.01 0.02 0.03 0.04 0.05 0.06 0.07
skew), rrot, is obtained as follows: Deflection, in.
Figure 3.19. Longitudinal stresses for slabs
d 0.0103
rrot = = exp ( 0.0582 LTE ) (17) between joints containing aligned and rotationally
d0 d0 misaligned dowels.
If the adjustment factor rrot is greater than 1, a value of 1
should be assumed.
For small joint openings, the slab with misaligned dowels
experienced slightly higher stresses than the slab with aligned
3.4.1.4 Faulting Prediction dowels at the joint. However, above a certain amount of joint
After computing the adjustment factors for all misalignment opening, the slab with aligned dowels experiences consistently
types, the equivalent diameter for the doweled joint should be higher stresses than the slab with misaligned dowels. This
computed using Equation 4. The effect of dowel misalignment phenomenon is caused by damage in the concrete surrounding
on the reduction of pavement life with respect to faulting the misaligned dowels, which reduces the ability of the joint
and/or the reduction in predicted faulting reliability then can to resist opening.
be determined using the MEPDG faulting model. Based on these observations, it can be concluded that dowel
misalignment itself is not a sufficient cause for joint lockup
and it does not cause significant additional stresses in the
3.4.2 JPCP Cracking
longitudinal direction. Also, the MEPDG cracking model can be
Joint lockup can cause transverse cracking. As discussed in used without modification to account for dowel misalignment.
Section 2.3.3, if joint lockup causes significant longitudinal Several conditions were evaluated using the finite element
stresses, then it can be accounted for by the MEPDG crack- slab model to investigate the effect of friction at the dowel-
ing model. PCC interface. These conditions included a joint with aligned
Earlier studies identified the possibility of high longitudinal dowels and a joint with two levels of misalignment (0.25 in.
stresses as a result of rotationally misaligned dowels. One of [6 mm] over 18 in. [457 mm] and 2 in. [51 mm] over 18 in.
these studies (Khazanovich et al., 2001) did not consider [457 mm]) for very high friction between the dowel and PCC.
concrete damage in the immediate area of the dowel and over- Figure 3.22 shows the computed longitudinal stresses for
estimated the joint capacity to resist opening. Another study these cases and the low friction cases for both an aligned and
(Prabhu et al., 2006) indicated the possibility of large longi- a misaligned dowel.
tudinal stresses for unrealistically large joint openings. Figure 3.20 indicates that aligned dowels with high friction
To consider the effect of possible joint lockup on longitu- result in significantly higher longitudinal stresses and higher
dinal stresses, the mid-slab stresses for aligned and misaligned resistance to joint opening than misaligned dowels with low
dowels were considered. For the misaligned case, each dowel friction. Also notice that both the low and high friction cases
was tilted by 2 in. [51 mm] over its 18 in. [457 mm] length, and for misaligned dowels did not converge for the entire range of
the dowels were configured so that adjacent dowels were rotated joint openings (due to failure of concrete around the dowels).
in opposite directions to provide the greatest potential for The analysis showed very high stress concentrations at the
joint lockup. Figure 3.19 presents the computed longitudinal surface in the vicinity of the dowels, which may cause micro-
stresses for various joint openings that represent different cracking or micro-spalling in the concrete around the dowels
degrees of thermal contractions. and lead to joint lockup.

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30
250 The minimum recommended concrete cover should allow
High Friction;
1 in./18 in. for adequate consolidation of concrete around dowels and
Rotation
200 may be increased for aggregate with maximum size greater
High Friction; than 1 in. [25 mm] based on local experience. Also, the min-
0.125 in./18
in. Rotation imum concrete cover may be increased if high possibility
150
for dowel corrosion exists. If the concrete cover is less than
Stress, psi.
High Friction;
Aligned the minimum required concrete cover, the equivalent dowel
100 diameter should be set equal to zero (i.e., undowelled joint
Low Friction;
Aligned is assumed.)
50
Low Friction;
2 in./18 in. 3.4.4 Pavement Performance Prediction
Rotation
0
The procedure for predicting pavement performance based
0 0.01 0.02 0.03 0.04 0.05
Deflection, in.
on the measured dowel misalignment level requires that an
equivalent dowel diameter be determined for each joint in a
Figure 3.20. Effect of dowel-PCC friction on pavement using the MEPDG procedures. The following obser-
longitudinal concrete stresses.
vations were considered in formulating the performance pre-
diction procedure:
While misalignment can result in higher longitudinal stresses, · The MEPDG prediction models were calibrated using the
joint lockup is more greatly affected by friction between the data contained in the LTPP database for 500-ft [152-m]
dowel and PCC. The laboratory tests identified the lack of long pavement sections.
dowel grease as a cause for higher dowel-concrete interface · Joints with severe dowel misalignment that are concentrated
friction and significant increase of the maximum pullout force. in a certain portion of the pavement section will have a
greater effect on performance than similar joints distributed
randomly along the pavement project.
3.4.3 Joint Spalling
· Nondestructive dowel location devices could be used to
In addition to joint performance considerations, the location investigate dowel misalignment in pavement projects.
of dowels with respect to the top PCC surface may present · The equivalent dowel diameter of each joint can be deter-
constructability and safety concerns. In some cases, joints are mined using the equations provided in Chapter 3.
not saw cut to the prescribed depth to avoid cutting through · The mean value of a pavement design parameter (pavement
the dowels located too close to the surface. In this case, joints thickness, subgrade resilient modulus, etc.) along the section
will not be formed and random cracking occurs. Also, a com- is used.
bination of vertical translation and tilt may result in low con-
crete cover at the end of the dowel. This condition may cause The following procedure is suggested for analyzing the effects
a high stress concentration in the concrete at the dowel end, of dowel misalignment on the performance of a uniform
possibly leading to spalling and exposure of the dowel to the pavement project:
pavement surface.
To address safety concerns related to the low concrete cover, 1. Use dowel alignment measurements to calculate the equiv-
it is recommended to saw cut through the dowels at the joint alent dowel diameter in each joint of the pavement project
if any dowel end is located within 2 in. [51 mm] of the top using the procedure described in Section 3.4.1.
pavement surface. This minimum concrete cover requirement 2. Establish "uniform sections" approximately 500 ft. [152 m]
is supported by the findings of a full scale laboratory study in long for the purposes of analysis and evaluation such
which a slab with 2 in. [51 mm] of concrete cover above the that all joints in the section have similar equivalent dowel
dowel performed as well as a slab with 3 in. [76 mm] of cover diameters. A series of several joints in any section with
for up to 10 million load cycles (Odden et al., 2003). Also, the relatively uniform equivalent dowel diameters that are
laboratory testing conducted in this project showed that a substantially different from the others in uniform sections
dowel with 1.25 in. [32 mm] of concrete cover sustained a may be evaluated as a separate uniform section.
shear force of 4.5 kip [20 kN], which is greater than the force 3. Compute the mean equivalent dowel diameter for each
required to be transferred by the critical dowel in a pavement section. Two or more adjacent sections with no significant
joint loaded by a 60-kip [267 kN] tandem axle load (based on difference in equivalent dowel diameters can be combined
ISLAB2000 analysis). into a single section.