c) Shear resistance tests
In the shear tests, it is assumed that the maximum
shear forces are caused by a horizontal load at a
certain distance from the foundation level (e.g.
vehicle impact). The maximum shear resistances
obtained in the tests are compared to the
theoretical values of two acting columns shoes.
The theoretical resistances are determined
according to EN 1993-1-8 considering both the
base plate and the bolt.
The different test setups for all three tests are
shown in Figure 9.
EVALUATION OF TEST RESULTS
BENDING RESISTANCE
The observed bending resistance moment Mobs
and the related failure modes of the column shoe
connections are summarized in Table 1. In the
two tests, compression failure of the concrete
and/or grout was observed. This means that the
ultimate capacity of the column shoe was not
reached, and the bending resistance moment is
higher than the value given in Table 1. For this
reason, these two tests will be disregarded in
the further evaluation.
The theoretical bending resistance Mt has been
calculated acc. to EN 1992-1-1 considering the
measured material properties for compressive
strength of the concrete and the grout,
yield strength of the rebars, as well as yield
strength of the anchor bolts. According to EAD,
the comparison of the test results with the
theoretical values mk = (Mobs/(ɳd0·Mt)) contains
a bending resistance factor ɳd0 ≤ 1.0 used for
the design of the test specimen. This value was
taken as ɳd0 = 1.0.
P P
Transducers
B30 -B
100
A) BENDING RESISTANCE TEST ARRANGEMENT
P P
Transducers
100 1300
B) BENDING STIFFNESS TEST ARRANGEMENT
100 1200
Test fgr b = d d1 fbolt,y Asp Mt ɳd,0 Mobs Mobs/(ɳd,0∙Mt) Failure mode
MPa mm mm MPa mm2 kNm - kNm -
B30-BS.2 1 53.2 310 50 803 561 209.8 1.00 215.7 1.03 Bolt
B30-B 1 49.9 310 50 803 561 208.5 1.00 220.2 1.06 Bolt
B30-BS.2 2 48.2 380 50 918 561 311.3 1.00 330.2 1.07 Bolt
B39-B 1 49.2 390 60 855 976 485.3 1.00 453.8 - concrete compression
B39-B 2 48.2 420 60 894 804 486.5 1.00 497.3 1.03 Bolt/column shoe
B52-B 1 49.9 500 70 964 1758 1273.4 1.00 1084.9 - concrete compression
B52-B 2 40.9 580 70 890 1479 1214.6 1.00 1343.8 1.11 Bolt/column shoe
B52-BS.2 2 43.5 580 70 890 1479 1218.9 1.00 1322.3 1.09 Bolt/column shoe
Mean value mm 1.07
Standard deviation sm 0.032
Characteristic value (unknown standard deviation) mk = mm - kn·s
Statistical factor acc. EN 1990: kn = 2,18 1,00
TABLE 1: EVALUATION OF THE BENDING RESISTANCE TESTS, RESULTS FROM 9, 10
100
-S
1300 700 50 1300 100
310 410
50 1300 100
310 410
B30 -BS
4000 2000 50
100
310 41
0
B30
P
3700 2000 50
C) SHEAR TEST ARRANGEMENT
FIGURE 9: EXAMPLES OF TEST SETUP ACCORDING TO EAD 1
The evaluation shown above clearly confirms
that the load bearing behavior of the column
with BOLDA® column shoe connection is equal
compared to the behavior of a monolithic
column.
PEIKKO CONNECTIONS 1/2021 51