Tests on existing floor to wall connections

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Tests on existing floor to wall connections

Messali, F.; Skroumpelou, Georgia

Publication date

2017

Document Version

Final published version

Citation (APA)

Messali, F., & Skroumpelou, G. (2017). Tests on existing floor to wall connections. Delft University of

Technology.

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This work is downloaded from Delft University of Technology.

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Date 30 June 2017 Corresponding author Francesco Messali

(f.messali@tudelft.nl)

TU Delft Large-scale testing campaign 2016

TESTS ON EXISTING FLOOR TO WALL

CONNECTIONS

Authors: Francesco Messali, Georgia Skroumpelou

Cite as: Messali, F. Skroumpelou, G. (2017). Tests on existing floor to wall connections. Report number

C31B67WP6-3, 30 June 2017. Delft University of Technology.

This document is made available via the website ‘Structural Response to Earthquakes’ and the TU Delft repository. While citing, please verify if there are recent updates of this research in the form of scientific papers.

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system of any nature, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior written permission of TU Delft.

TU Delft and those who have contributed to this publication did exercise the greatest care in putting together this publication. This report will be available as-is, and TU Delft makes no representations of warranties of any kind concerning this Report. This includes, without limitation, fitness for a particular purpose, non-infringement, absence of latent or other defects, accuracy, or the presence or absence of errors, whether or not discoverable. Except to the extent required by applicable law, in no event will TU Delft be liable for on any legal theory for any special, incidental consequential, punitive or exemplary damages arising out of the use of this report.

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Version 01 – Final 30/06/2017

1 Introduction

The current document reports the outcomes of a series of tests performed on replicated floor to walls connections. These anchorages between a masonry pier and a concrete floor are typical of those terraced house typology where the concrete floors are not directly supported by the masonry piers of the façades, and consist of steel threaded rods M6, of quality 4.6.

The same typology of anchorages was adopted during the experimental testing campaign performed in 2015 for the characterization of Dutch masonry (in the pushover test on an assembled masonry structure at TUD [7] and on the dynamic test on a full-scale terraced house at Eucentre [6]) to prevent the out-of-plane failure of the piers (Figure 1). During the campaign their performances were not investigated. Therefore, the presented tests aimed at providing a complete characterization of the behaviour of this typology of connections under either tensile axial or shear loading, for both monotonic and cyclic loading.

The obtained results will be used as inputs to calibrate the numerical models that simulate the interaction between the concrete floors and the piers. Specific attention will be devoted to identify the initial stiffness of the connection under gravity loads.

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2 Construction of the specimens

In order to characterize the behaviour of the concrete floor to wall connections under both shear and axial loading, different types of specimens were constructed: (i) concrete blocks with embedded threaded bars and (ii) masonry couplets with embedded threaded bars for axial testing; (iii) specimens which combined both concrete blocks and masonry couplets for shear testing. The specimens are described in detail in the following sections (Section 4.1.1, Section 5.1.1 and Section 6.1.1, respectively).

The specimens were partially built by Bestcon B.V. and then completed in the Stevin II laboratory at the Delft University of Technology. The concrete blocks were prefabricated and the masonry couplets were built in the laboratory (Figure 2, Figure 3, and Figure 4).

The mortar was prepared by adopting fixed water content per bag of mix: 2.8 l/bag for calcium silicate masonry.

During the construction, the temperature and the relative humidity were measured. For every mortar cast, the fluidity of the mortar was determined in agreement with EN 1015-3:1999 [2].

Mortar samples were collected to evaluate the flexural and compressive strength.

Figure 2 – Complete concrete-floor-to-wall connection specimens (concrete blocks connected to CaSi masonry couplets)

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Version 01 – Final 30/06/2017 Figure 3 – Concrete floor specimens (concrete blocks)

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3 Types of tests and specimens

Types of specimens

A series of tests have been performed on concrete floor to masonry wall connections. In such connections the concrete floor is connected to the calcium silicate piers by means of threaded bars M6, quality 4.6. The bars are casted in the concrete and the last 75 mm of each treaded bar inside the concrete block is surrounded by a polystyrene block. The other end of the bar is embedded in the mortar of the calcium silicate wall. The distance between the wall and the floor is 22 mm.

Depending on the type of applied loading, three general types of specimens have been designed: i.

ii. For pull-out tests:

 Threaded bar embedded in concrete block to represent the anchorage in the concrete floor (Figure 5).

 Threaded bar embedded in calcium silicate couplet to represent the anchorage in the masonry pier (Figure 6).

iii. For shear tests:

 Threaded bar embedded both in concrete block and calcium silicate couplet to represent the complete connection (Figure 7).

Variations regarding the presence or the size of a washer will be discussed in the individual sections of each typology (Section 4.1.1, Section 5.1.1 and Section 6.1.1, respectively).

Figure 5 – Concrete floor specimens (concrete blocks).

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Version 01 – Final 30/06/2017 Figure 7 – Complete floor-to-wall connection.

Name of the specimens

Axial tests

Table 1 – Types of specimens for axial tests.

Name Specimen _procedureLoading Washer Precompression Number of _tests TUD_ANC-FN0 Concrete floor

Monotonic tension - - 10 TUD_ANC-WN0 CaSi couplet No 0.0MPa 2 TUD_ANC-WN1 0.1MPa 2 TUD_ANC-WN3 0.3MPa 2 TUD_ANC-WS0 Small 0.0MPa 2 TUD_ANC-WS1 0.1MPa 2 TUD_ANC-WS3 0.3MPa 2 TUD_ANC-WB0 Big 0.0MPa 4 TUD_ANC-WB1 0.1MPa 4 TUD_ANC-WB3 0.3MPa 4

Table 2 – Naming of specimens for axial tests.

TUD_ANC-xyz: x y z

F Concrete Floor N No washer 0 Precompression=0.0MPa W Masonry Wall S Small washer 1 Precompression=0.1MPa B Big washer 3 Precompression=0.3MPa

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Shear tests

Table 3 – Types of specimens for shear tests.

Name Specimen _procedureLoading Washer Precompression Number of _tests TUD_ANC-CH0 Complete connection Monotonic horizontal - - 2

TUD_ANC-CV0 Monotonic vertical 6

TUD_ANC-CV1 Cyclic vertical - 1st 6

TUD_ANC-CV2 Cyclic vertical - 2nd 1

Table 4 – Types of specimens for shear tests.

TUD_ANC-xyz: x y z

C Complete Connection H Horizontal 0 Protocol 0 (Monotonic) V Vertical 1 Protocol 1 (Cyclic 1st)

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4 Axial tests on concrete floor specimens

Testing procedure

Description of the specimens

The geometry and the dimensions of the specimen are shown in Figure 8.

Figure 8 – Dimensions of concrete floor specimens (concrete blocks)

Test set-up

The test apparatus is presented in Figure 9 and comprehends:

i. A horizontal steel plate (4) connected to a contrast beam by means of steel bolts M24 (5) to restrict the upward vertical movement of the concrete part of the specimen (1). This plate has a hole at the centre for the threaded bar (2).

ii. A test machine to apply the vertical load. The pull-out load acts in a vertical direction using displacement controlled apparatus. The apparatus is composed by a 4.5 tons jack and a double cylindrical joint (between the load cell and the clamp), which reduce possible eccentricities and prevent torsion failures of the tie during loading. The machine is provided with a clamp (3) for gripping efficiently the free end of the threaded bar; the distance between the clamp and the concrete block should be equal to 22 mm.

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Loading scheme

The specimen is placed in the test machine such that the threaded bar is axial and aligned at the center of the test machine. The threaded bar is clamped so that it has a free distance from the concrete block equal to 22 mm.

The pull-out load is applied in displacement control. The pull-out behavior of the threaded bars (tensile loading) is determined by monotonically increasing the displacement with a rate of 0.1 mm/s up to failure.

Experimental results on TUD_ANC-FN0-i specimens (concrete

blocks)

The observed failure mechanism showed elongation and fracture of the steel threaded bar (Figure 10). The position of fracture varied: in some specimens the treaded bar failed inside the polystyrene block, while in others it failed closer to the clamp. However, the different position is not related to different strength of the bar, nor to different ductility.

Figure 11, Figure 12 and Table 5 report the force-displacement curves for each single performed test and a summary of the results. The behaviour of all the specimens was consistent and small variations are observed. The anchoring of the bar in the concrete was efficient up to failure of the specimens. The critical component of the connection is therefore the steel threaded bar, which fails in tension, and not the grip in the concrete block. Relatively small ductility is shown, since the threaded bars use cold drawn steel.

Figure 10 – Failure types for monotonic tensile loading of concrete specimens.

0 2 4 6 8 10 12 0 1 2 3 4 5 6 P u ll -o u t fo rc e ( k N ) Pull-out displacement (mm) TUD_ANC-FN0-02 0 2 4 6 8 10 12 0 1 2 3 4 5 6 P u ll -o u t fo rc e ( k N ) Pull-out displacement (mm) TUD_ANC-FN0-03

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Version 01 – Final 30/06/2017 Figure 11 – Force displacement curve for monotonic tensile loading of concrete specimens.

0 2 4 6 8 10 12 0 1 2 3 4 5 6 P u ll -o u t fo rc e ( k N ) Pull-out displacement (mm) TUD_ANC-FN0-05 0 2 4 6 8 10 12 0 1 2 3 4 5 6 P u ll -o u t fo rc e ( k N ) Pull-out displacement (mm) TUD_ANC-FN0-06 0 2 4 6 8 10 12 0 1 2 3 4 5 6 P u ll -o u t fo rc e ( k N ) Pull-out displacement (mm) TUD_ANC-FN0-07 0 2 4 6 8 10 12 0 1 2 3 4 5 6 P u ll -o u t fo rc e ( k N ) Pull-out displacement (mm) TUD_ANC-FN0-08 0 2 4 6 8 10 12 0 1 2 3 4 5 6 P u ll -o u t fo rc e ( k N ) Pull-out displacement (mm) TUD_ANC-FN0-09 0 2 4 6 8 10 12 0 1 2 3 4 5 6 P u ll -o u t fo rc e ( k N ) Pull-out displacement (mm) TUD_ANC-FN0-10

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Version 01 – Final 30/06/2017 Figure 12 – Summary of the “Force-Displacement curves” for monotonic tensile loading of concrete

specimens.

Table 5 – Summary of results for monotonic tensile loading of concrete specimens.

Specimen Peak vertical force [kN] Displacement [mm]

TUD_ANC-FN0-02 10.48 3.76 TUD_ANC-FN0-03 10.26 3.54 TUD_ANC-FN0-04 9.97 3.10 TUD_ANC-FN0-05 10.15 3.55 TUD_ANC-FN0-06 10.19 3.39 TUD_ANC-FN0-07 9.87 3.77 TUD_ANC-FN0-08 9.94 3.61 TUD_ANC-FN0-09 10.24 3.09 TUD_ANC-FN0-10 11.21 3.66 Average 10.26 3.50 Standard deviation 0.40 0.25 Coefficient of variation 3.9% 7.3%

0

2

4

6

8

10

12

0

1

2

3

4

5

6 V

e

rt

ic

a

l

fo

rc

e

(

k

N

)

Vertical displacement (mm)

TUD_ANC-FN0-02 TUD_ANC-FN0-03 TUD_ANC-FN0-04 TUD_ANC-FN0-05 TUD_ANC-FN0-06 TUD_ANC-FN0-07 TUD_ANC-FN0-08 TUD_ANC-FN0-09 TUD_ANC-FN0-10 Average

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5 Axial tests on calcium silicate masonry specimens

Testing procedure

The specimens are described in Section 3.1.

In addition, the influence of the presence and of the size of a washer at the other face of the masonry wall providing some resistance to the pull-out was investigated.

Three different cases were analysed:

 No washer between the nut and the couplet (Figure 13a).

 A normal washer for M6 between the nut and the couplet (outer diameter: 10mm) (Figure 13b).  A big washer for M6 between the nut and the couplet (outer diameter: 30mm) (Figure 13c).

(a) (b) (c)

Figure 13 – Different washer cases for masonry couplets: (a) No washer; (b) Small washer; (c) Big washer

Figure 14 – Dimensions of masonry wall specimens (CaSi couplets).

Test set-up

The test apparatus is presented in Figure 15, and comprehends:

i. Supports for the specimen. The support system consists of two couples of hardwood bearers (7) placed at the sides and bottom surfaces of the specimen (1). A horizontal steel plate (4) connected to a contrast beam by means of steel bolts M24 (5) to restrict the upward vertical movement of the masonry part of the specimen. This plate has a hole at the centre for the threaded bar (2). The hardwood bearers do not apply any restraint against splitting of the specimen (apart from the friction generated at the reaction due to the applied load, as suggested by EN 846-5:2012 [4]).

ii. A means of applying and maintaining a constant compressive stress on the couplet. The force is provided by a hydraulic jack (9) acting in the horizontal direction and perpendicular to the bed joint plane. The system is self-equilibrated by four threaded bars (6) connecting the vertical plates (8). iii. A test machine to apply the vertical load. The pull-out load acts in a vertical direction using

displacement controlled apparatus. The apparatus is composed by a 4.5 tons jack and a double cylindrical joint (between the load cell and the clamp), which reduce possible eccentricities and

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Version 01 – Final 30/06/2017 prevent torsion failures of the threaded bar during loading. The machine is provided with a clamp (3) for gripping efficiently the free end of the threaded bar; the distance between the clamp and the couplet should be equal to 22 mm.

Figure 15 – Set-up for pull-out testing of masonry wall specimens (CaSi couplets).

Loading scheme

The masonry couplets represent the other end of the complete connection, therefore they should be tested with the same procedure applied to the concrete blocks. The specimen is placed in the test machine such that the threaded bar is axial and aligned at the center of the test machine. The threaded bar is clamped to have a free distance from the couplet equal to 22 mm.

The specimen is maintained under constant lateral pre-compression while the pull-out load is applied to the threaded bar. Three different levels of pre-compression are investigated (0.0 N/mm2_{, 0.1 ± 0.01 N/mm}2_and 0.3 ± 0.01 N/mm2_).

The pull-out load is applied in displacement control. The pull-out behavior of the threaded bars (tensile loading) is determined by monotonically increasing the displacement with a rate of 0.1 mm/s up to failure. Due to the small free distance between the couplet and the clamp (22 mm) and the presence of the restrictive horizontal steel plate there is not enough space for compressive and cyclic tests to be performed, therefore only monotonic tensile loading was applied.

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Experimental results on TUD_ANC-WNz-i specimens

(CaSi masonry couplets – no washer)

A single failure mechanism was observed, regardless of the applied precompression level, with failure of the mortar around the threaded bar and sometimes with splitting of the couplet (Figure 16).

Figure 16 – Failure for monotonic tensile loading of masonry specimens with no washer.

The following sections (5.2.1-5.2.3) show the force-displacement diagrams for the pull-out tests performed on specimens lacking of the washer, for different levels of precompression.

The diagrams for each curve and for the average behaviour, and a tabulated summary of the results are reported.

A qualitatively similar behaviour is obtained for each specimen, with a hyperbolic reduction of resistance after the peak resistance is attained.

The influence of the lateral precompression is shortly discussed in section 5.2.4.

Precompression level: 0.0 N/mm2 _{(TUD_ANC_WN0)} Figure 17 shows the force-displacement diagram for each single test.

Figure 18 and Table 6 reports a summary of the force-displacement curves and of the main results, respectively.

Figure 17 – Force displacement curve for monotonic tensile loading of masonry specimens with no washer at a precompression level of 0.0 N/mm2_. 0 0.5 1 1.5 2 0 20 40 60 80 100 P u ll -o u t fo rc e (k N ) Pull-out displacement (mm) TUD_ANC-WN0-08 0 0.5 1 1.5 2 0 20 40 60 80 100 P u ll -o u t fo rc e (k N ) Pull-out displacement (mm) TUD_ANC-WN0-16

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Figure 18 – Summary of the “Force-Displacement curves” for monotonic tensile loading of masonry specimens with no washer at a precompression level of 0.0 N/mm2_.

Table 6 – Summary of results for monotonic tensile loading of masonry specimens with no washer at a precompression level of 0.0 N/mm2_.

TUD_ANC-WN0-08 0.69 0.51

TUD_ANC-WN0-16 0.72 0.32

Average 0.70 0.42

Standard deviation 0.02 0.13

Coefficient of variation 2.3% 31.4%

Precompression level: 0.1 ± 0.01 N/mm2 _{(TUD_ANC_WN1)} Figure 19 shows the force-displacement diagram for each single test.

Figure 19 – Force displacement curve for monotonic tensile loading of masonry specimens with no washer at a precompression level of 0.1 N/mm2_. 0 0.5 1 1.5 2 0 20 40 60 80 100 F o rc e (k N ) Displacement (mm) TUD_ANC-WN0-08 TUD_ANC-WN0-16 Average 0 0.5 1 1.5 2 0 20 40 60 80 100 P u ll -o u t fo rc e (k N ) Pull-out displacement (mm) TUD_ANC-WN1-15 0 0.5 1 1.5 2 0 20 40 60 80 100 P u ll -o u t fo rc e (k N ) Pull-out displacement (mm) TUD_ANC-WN1-19

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TUD_ANC-WN1-15 0.83 0.66

TUD_ANC-WN1-19 1.87 0.61

Average 1.35 0.64

Precompression level: 0.3 ± 0.01 N/mm2 _{(TUD_ANC_WN3)} Figure 21 shows the force-displacement diagram for each single test.

Figure 21 – Force displacement curve for monotonic tensile loading of masonry specimens with no washer at a precompression level of 0.3 N/mm2_. 0 0.5 1 1.5 2 0 20 40 60 80 100 F o rc e (k N ) Displacement (mm) TUD_ANC-WN1-15 TUD_ANC-WN1-19 Average 0 0.5 1 1.5 2 0 20 40 60 80 100 P u ll -o u t fo rc e (k N ) Pull-out displacement (mm) TUD_ANC-WN3-20 0 0.5 1 1.5 2 0 20 40 60 80 100 P u ll -o u t fo rc e (k N ) Pull-out displacement (mm) TUD_ANC-WN3-13

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TUD_ANC-WN3-20 1.79 0.67

TUD_ANC-WN3-13 1.73 0.54

Average 1.76 0.60

Influence of the lateral precompression level

Figure 23 shows the force-displacement diagrams for every test performed on specimens lacking of washer at different levels of lateral precompression.

The qualitative behaviour is similar for every test, with a hyperbolic reduction of resistance after the peak resistance is attained. The value of the peak load is proportional to the lateral precompression level. This is consistent with the observed failure mode, that is governed by sliding of the bar in the mortar joint. A Coulomb frictional law may be used to describe mathematically the behaviour.

The average results are summarised in Table 9. 0 0.5 1 1.5 2 0 20 40 60 80 100 F o rc e (k N ) Displacement (mm) TUD_ANC-WN3-20 TUD_ANC-WN3-13 Average

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Version 01 – Final 30/06/2017 Figure 23 – Collective results for monotonic tensile loading of masonry specimens with no washer at the

three different levels of precompression.

Table 9 – Summary of results for monotonic tensile loading of masonry specimens with no washer at each level of precompression.

Level of precompression [MPa] Average peak force [kN] Average displacement [kN]

0.0 0.70 0.42 0.1 1.35 0.64 0.3 1.76 0.60 0 0.5 1 1.5 2 0 20 40 60 80 100

F

or

ce

(

k

N

)

Displacement (mm)

0.0MPa 0.1MPa 0.3MPa Average-0.0MPa Average-0.1MPa Average-0.3MPa

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Experimental

results

on

TUD_ANC-WSz-i

specimens

(CaSi masonry couplets – small washer)

The types of failure in the case of the small washer were similar but not identical for each level of precompression, therefore they will be presented individually.

Precompression level: 0.0 N/mm2 _{(TUD_ANC_WS0)}

Piercing and expulsion of the cone of mortar around the washer as well as separation of the specimens were observed, with detachment of the mortar (Figure 24).

Figure 24 – Failure for monotonic tensile loading of masonry specimens with small washer at a precompression level of 0.0 N/mm2_.

Figure 25, Figure 26 and Table 10 report the force-displacement curves for each single performed test and a summary of the results.

After the peak resistance is attained a brittle reduction of capacity is observed, followed by a stable behaviour with a small residual resistance of the connection up to large displacements (>80 mm).

A large difference was observed between the peak forces of the two tested specimens. However, only two tests do not allow to deduce conclusions about this difference.

Figure 25 – Force displacement curve for monotonic tensile loading of masonry specimens with small washer at a precompression level of 0.0 N/mm2_.

0 1 2 3 4 5 6 7 0 20 40 60 80 100 P u ll -o u t fo rc e (k N ) Pull-out displacement (mm) TUD_ANC-WS0-01 0 1 2 3 4 5 6 7 0 20 40 60 80 100 P u ll -o u t fo rc e (k N ) Pull-out displacement (mm) TUD_ANC-WS0-07

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Figure 26 – Summary of the “Force-Displacement curves” for monotonic tensile loading of masonry specimens with small washer at a precompression level of 0.0 N/mm2_.

Table 10 – Summary of results for monotonic tensile loading of masonry specimens with small washer at a precompression level of 0.0 N/mm2_.

TUD_ANC-WS0-01 3.15 8.99

TUD_ANC-WS0-07 1.74 0.63

Average 2.44 4.81

Precompression level: 0.1 ± 0.01 N/mm2 _{(TUD_ANC_WS1)}

For a precompression of 0.1MPa more severe cracking of the mortar was observed than in the case of zero precompression. Again, detachment between bricks and mortar occurred. After peak, the behaviour is more stable for signigicantly large displacements (~40 mm), followed by quasi-brittle softening.

Figure 27 – Failure for monotonic tensile loading of masonry specimens with small washer at a precompression level of 0.1 N/mm2_. 0 1 2 3 4 5 6 7 0 40 80 120 F o rc e (k N ) Displacement (mm) TUD_ANC-WS0-01 TUD_ANC-WS0-07 Average-Washer

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Version 01 – Final 30/06/2017 Figure 28 – Force displacement curve for monotonic tensile loading of masonry specimens with small

washer at a precompression level of 0.1 N/mm2_.

Table 11 – Summary of results for monotonic tensile loading of masonry specimens with small washer at a precompression level of 0.1 N/mm2_.

TUD_ANC-WS1-04 3.66 9.47

TUD_ANC-WS1-10 4.41 11.76

Average 4.03 10.62

Precompression level: 0.3 ± 0.01 N/mm2 _{(TUD_ANC_WS3)}

The higher level of lateral precompression causes the splitting of the calcium silicate bricks, additionally to piercing of the mortar and mortar/brick detachment (Figure 30).

The post-peak behaviour is characterised by an initial sudden loss of resistance followed by a more gradual softening behaviour.

0 1 2 3 4 5 6 7 0 20 40 60 80 100 P u ll -o u t fo rc e (k N ) Pull-out displacement (mm) TUD_ANC-WS1-04 0 1 2 3 4 5 6 7 0 20 40 60 80 100 P u ll -o u t fo rc e (k N ) Pull-out displacement (mm) TUD_ANC-WS1-10 0 1 2 3 4 5 6 7 0 40 80 120 F or ce ( k N ) Displacement (mm) TUD_ANC-WS1-04 TUD_ANC-WS1-10 Average-Washer

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Version 01 – Final 30/06/2017 Figure 30 – Failure curve for monotonic tensile loading of masonry specimens with small washer at a

precompression level of 0.3 N/mm2_.

Figure 31 – Force displacement curve for monotonic tensile loading of masonry specimens with small washer at a precompression level of 0.3 N/mm2_.

0 1 2 3 4 5 6 7 0 20 40 60 80 100 P u ll -o u t fo rc e (k N ) Pull-out displacement (mm) TUD_ANC-WS3-11 0 1 2 3 4 5 6 7 0 20 40 60 80 100 P u ll -o u t fo rc e (k N ) Pull-out displacement (mm) TUD_ANC-WS3-22 0 1 2 3 4 5 6 7 0 40 80 120 F or ce ( k N ) Displacement (mm) TUD_ANC-WS3-11 TUD_ANC-WS3-22 Average-Washer

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Version 01 – Final 30/06/2017 Table 12 – Summary of results for monotonic tensile loading of masonry specimens with small washer at a

TUD_ANC-WS3_11 6.48 19.33

TUD_ANC-WS3-22 6.19 14.81

Average 6.34 17.07

Influence of precompression level

The graph depicted in Figure 33 clearly shows that as the precompression stress increases, both the peak pull-out forces and the related displacements increase. Moreover, at higher precompression levels, less brittle behaviour is observed.

Figure 33 – Collective results for monotonic tensile loading of masonry specimens with small washer at the three different levels of precompression.

Table 13 – Summary of results for monotonic tensile loading of masonry specimens with small washer at each level of precompression.

0.0 2.44 4.81 0.1 4.03 10.62 0.3 6.34 17.07 0 1 2 3 4 5 6 7 0 40 80 120 F or ce ( k N ) Displacement (mm) 0.0Mpa 0.1MPa 0.3MPa Average-0.0MPa Average-0.1MPa Average-0.3MPa

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Experimental

results

on

TUD_ANC-WBz-i

specimens

(CaSi masonry couplets – big washer)

The types of failure in the case of the big washer were similar but not identical for each level of precompression, therefore they will be presented individually.

Precompression level: 0 N/mm2 _{(TUD_ANC_WB0)}

For zero precompression, cracking of the mortar, piercing around the big washer and separation of the specimen were observed, with separation between one brick and the mortar joint being the critical factor (Figure 34). The post-peak behaviour is extremely brittle. Figure 35, Figure 36 and Table 14 report the force-displacement curves for each single performed test and a summary of the results.

Figure 34 – Failure for monotonic tensile loading of masonry specimens with big washer at a precompression level of 0.0 N/mm2_.

Figure 35 – Force displacement curve for monotonic tensile loading of masonry specimens with big washer at a precompression level of 0.0 N/mm2_. 0 5 10 15 20 0 10 20 30 40 P ul l-o ut fo rce (k N ) Pull-out displacement (mm) TUD_ANC-WB0-14 0 5 10 15 20 0 10 20 30 40 P ul l-o ut fo rce (k N ) Pull-out displacement (mm) TUD_ANC-WB0-27 0 5 10 15 20 0 10 20 30 40 P ul l-o ut fo rce (k N ) Pull-out displacement (mm) TUD_ANC-WB0-29

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Version 01 – Final 30/06/2017 Figure 36 – Summary of the “Force-Displacement curves” for monotonic tensile loading of masonry

specimens with big washer at a precompression level of 0.0 N/mm2_.

Table 14 – Summary of results for monotonic tensile loading of masonry specimens with big washer at a precompression level of 0.0 N/mm2_.

TUD_ANC-WB0-14 7.62 2.67 TUD_ANC-WB0-27 9.97 2.95 TUD_ANC-WB0-29 8.34 3.09 Average 8.64 2.90 Standard deviation 1.20 0.22 Coefficient of variation 13.9% 7.4%

Precompression level: 0.1 ± 0.01 N/mm2 _{(TUD_ANC_WB1)}

Cracking of the mortar, piercing around the big washer and separation of the specimen were observed (Figure 37). The separation of the specimens determined a sudden variation in the applied lateral precompression. In addition, the big washer was bent and scraped against the bricks leading to deterioration or even splitting of the bricks.

This failure mode leads to a gradual reduction of resistance in the post-peak phase. The force-displacement curves for each single test and a summary of the results are reported in Figure 38, Figure 39 and Table 15.

Figure 37 – Failure for monotonic tensile loading of masonry specimens with big washer at a precompression level of 0.1 N/mm2_. 0 5 10 15 20 0 10 20 30 40 F o rce (k N ) Displacement (mm) TUD_ANC-WB0-14 TUD_ANC-WB0-27 TUD_ANC-WB0-29 Average-Big Washer

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Version 01 – Final 30/06/2017 Figure 38 – Force displacement curve for monotonic tensile loading of masonry specimens with big washer

at a precompression level of 0.1 N/mm2_.

Figure 39 – Summary of the “Force-Displacement curves” for monotonic tensile loading of masonry specimens with big washer at a precompression level of 0.1 N/mm2_.

0 5 10 15 20 0 10 20 30 40 P ul l-o ut fo rce (k N ) Pull-out displacement (mm) TUD_ANC-WB1-12 0 5 10 15 20 0 10 20 30 40 P ul l-o ut fo rce (k N) Pull-out displacement (mm) TUD_ANC-WB1-03 0 5 10 15 20 0 10 20 30 40 P ul l-o ut fo rce (k N ) Pull-out displacement (mm) TUD_ANC-WB1-05 0 5 10 15 20 0 10 20 30 40

F

o

rce

(k

N

)

Displacement (mm)

TUD_ANC-WB1-12 TUD_ANC-WB1-03 TUD_ANC-WB1-05 Average-Big Washer

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Version 01 – Final 30/06/2017 Table 15 – Summary of results for monotonic tensile loading of masonry specimens with big washer at a

TUD_ANC-WB1-12 15.07 8.28 TUD_ANC-WB1-03 14.75 7.60 TUD_ANC-WB1-05 15.68 8.44 Average 15.17 8.11 Standard deviation 0.47 0.45 Coefficient of variation 3.1% 5.5%

Precompression level: 0.3 ± 0.01 N/mm2 _{(TUD_ANC_WB3)}

As shown in Figure 40, for a precompression of 0.3 MPa the mortar failed along the threaded bar but the washer did not pierce through the specimen. The calcium silicate bricks split and the thread of the bar failed starting from the washer and continuing towards the other side of the couplet (jagged part of the force-displacement curve, Figure 41). This type of failure is extremely brittle.

Figure 40 – Failure for monotonic tensile loading of masonry specimens with big washer at a precompression level of 0.3 N/mm2_. 0 5 10 15 20 0 10 20 30 40 P ul l-o ut fo rce (k N ) Pull-out displacement (mm) TUD_ANC-WB3-18 0 5 10 15 20 0 10 20 30 40 P ul l-o ut fo rce (k N ) Pull-out displacement (mm) TUD_ANC-WB3-02

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Version 01 – Final 30/06/2017 Figure 41 – Force displacement curve for monotonic tensile loading of masonry specimens with big washer

at a precompression level of 0.3 N/mm2_.

Figure 42 – Summary of the “Force-Displacement curves” for monotonic tensile loading of masonry specimens with big washer at a precompression level of 0.3 N/mm2_.

Table 16 – Summary of results for monotonic tensile loading of masonry specimens with big washer at a precompression level of 0.3 N/mm2_.

TUD_ANC-WB3-18 18.62 6.35 TUD_ANC-WB3-02 17.15 7.29 TUD_ANC-WB3-06 17.91 7.22 Average 17.89 6.95 Standard deviation 0.73 0.53 Coefficient of variation 4.1% 7.6% 0 5 10 15 20 0 10 20 30 40 P ul l-o ut fo rce (k N ) Pull-out displacement (mm) TUD_ANC-WB3-06

0

5

10

15

20

0

10

20

30

40 F

o

rce

(k

N

)

Displacement (mm)

TUD_ANC-WB3-18 TUD_ANC-WB3-02 TUD_ANC-WB3-06 Average-Big Washer

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Influence of the precompression level

The behaviour of the masonry couplets for each level of precompression was significantly different (Figure 43, Table 17).

The increase of lateral precompression leads to higher resistance of the connection. However, while the absence of precompression and high (0.3 MPa) stresses determine the brittle failure of the specimen, at 0.1 MPa of lateral precompression the specimen behaves in a more ductile way.

The type of failure was similar in every tested specimen, with cracking of the mortar, separation between the brick and the mortar joint and final splitting of the unit. Therefore, the aforementioned different ductility seems not to be related to the observed failure. Further investigation may be needed.

Figure 43 – Collective results for monotonic tensile loading of masonry specimens with big washer at the three different levels of precompression.

Table 17 – Summary of results for monotonic tensile loading of masonry specimens with big washer at each level of precompression.

0.0 8.64 2.90 0.1 15.17 8.11 0.3 17.89 6.95

0

5

10

15

20

0

10

20

30

40 F

o

rce

(k

N

)

Displacement (mm)

0.0MPa 0.1MPa 0.3MPa Average-0.0MPa Average-0.1MPa Average-0.3MPa

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Summary of results

The influence of two variables was investigated during the testing of masonry specimens under monotonic tensile loading:

 The presence and the size of a washer between the nut and the couplet  The level of lateral precompression at which the specimen is loaded The collective results for all the different cases are presented in Table 18.

Washer

As discussed in the previous sections, larger washer give larger peak loads and corresponding displacement at peak, since the threaded bar, after the failure of the mortar around the thread, can simply slide through the mortar if there is no washer or its diameter is smaller (or equal) to the mortar joint thickness. When the outer diameter of the washer increases and exceeds the thickness of the mortar the resistance increases dramatically: the washer interacts not only with the mortar but also with the calcium silicate bricks providing a much effective resistance. The use of washers of large diameter (the so-called ‘karrosseriering’) is strongly advised.

Precompression

Independently of the used washer, the increase of the precompression gives larger peak force. This does not apply to the post-peak behaviour, as discussed in section 5.4.4, and to the displacement at peak.

Table 18 – Collective results for monotonic tensile loading of masonry specimens with different types of washers at each level of precompression.

Type of washer

No washer Small washer Big washer

Peak Force [kN] Displacement [mm] Peak Force [kN] Displacement [mm] Peak Force [kN] Displacement [mm] P re co m p re ss io n [Mpa] 0.0 0.70 0.42 2.44 4.81 8.64 2.90 0.1 1.35 0.64 4.03 10.62 15.17 8.11 0.3 1.76 0.60 6.34 17.07 17.89 6.95

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6 Shear tests on concrete-floor-to-wall connections

Testing procedure

The specimen is described in Section 3.1. During the testing phase a big washer and a nut were added at the outer side of the masonry part of the specimen to prevent pull-out and ensure pure shear loading.

Figure 44 – Dimensions of complete concrete-floor-to-wall connection specimens (concrete blocks connected to CaSi masonry couplets)

Test set-up

The test apparatus is presented in Figure 45Figure 15, and comprehends:

i. Supports for the specimen. The support system consists of four horizontal steel plates (5) and eight steel bolts M24 (6). Each couple of steel plates is placed at the top and bottom of each part of the specimen (one couple for the masonry part and one couple for the concrete part) and with the help of the steel rods the concrete part is fixed and the masonry part is clamped to the load cell. For the masonry part, hardwood bearers are placed at the top and bottom to leave space for the concrete part to move vertically without reaching the steel plates. Teflon sheets are placed between the wooden pieces and the steel plates in order for the couplet to be able to move horizontally and compensate for the reduction of the 22 mm distance between the masonry and the concrete block as the two parts move relatively in the vertical direction. The hardwood bearers do not apply any restraint against splitting of the specimen (apart from the friction generated at the reaction due to the applied load, as suggested by EN 846-5:2012 [4]). A temporary support is placed under the bottom horizontal plate of the couplet to keep the complete specimen aligned until the bottom plate is sufficiently bolted to the top plate. Then the support is removed.

ii. A test machine to apply the vertical load. The shear load acts in a vertical direction using displacement controlled apparatus. The apparatus is composed by a 4.5 tons jack and a double cylindrical joint (between the load cell and the clamp), which reduce possible eccentricities and prevent torsion failures of the threaded bar during loading. The top horizontal plate of the masonry part is screwed to the load-cell to vertically displace the couplet.

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Version 01 – Final 30/06/2017 Figure 45 – Set-up for shear testing of complete concrete-floor-to-wall connection specimens (concrete

blocks connected to CaSi masonry couplets)

Loading scheme

There are two directions in which the shear loading can be applied: horizontal (parallel to the mortar) and vertical (perpendicular to the mortar).

Horizontal shear

For horizontal shear, only monotonic tests were performed as the absence of lateral restriction led to separation of the masonry part of the specimen and cyclic loading would not give useful results because of the movement of the threaded bar inside the broken mortar. Note that this configuration may not be completely realistic in a building, where the couplets are subject to confining forces provided by the surrounding structure.

The shear behavior of the specimens is determined by monotonically increasing the displacement with a rate of 0.1 mm/s up to failure.

Vertical shear

When performing tests of vertical shear loading the masonry part of the specimen is not allowed to open as it is restricted between the two horizontal steel plates. Three different loading schemes are followed:

 Protocol V0 (monotonic shear protocol): The shear behaviour of the specimens is determined by monotonically increasing the displacement with a rate of 0.1 mm/s up to failure.

 Protocol V1 (cyclic shear protocol – small number of cycles for each amplitude): The displacement is cyclically varied by applying both upward and downward (shear) loads on the tie, as depicted in  Figure 46.

 Protocol V2 (cyclic shear protocol – large number of cycles for each amplitude): The displacement is cyclically varied by applying both upward and downward (shear) loads on the tie, as depicted in Figure 47.

The last protocol was introduced in order to investigated the influence of the number of cycles on the force-displacement behavior of the specimens.

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Version 01 – Final 30/06/2017 Figure 46 – Cyclic protocol V1.

Figure 47 – Cyclic protocol V2.

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Experimental results on TUD_ANC-CHz-i specimens (complete

connection – horizontal shear loading)

Monotonic tests (TUD_ANC-CH0)

During the monotonic horizontal shear loading of the complete specimens the masonry part separated due to lack of lateral restriction. Therefore, only two tests were performed. Bending of the threaded bar, cracking of the mortar and separation of the specimens were observed.

Figure 48 – Failure for monotonic horizontal shear loading of concrete-floor-to-wall connections. Figure 49, Figure 50 and Table 19 report the force-displacement curves for each single performed test and a summary of the results.

Figure 49 – Force displacement curve for monotonic horizontal shear loading of concrete-floor-to-wall connections. 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 0 10 20 30 40 50 60 70 S h ea r fo rc e (k N ) Shear displacement (mm) TUD_ANC-CH0-12 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 0 20 40 60 80 S h ea r fo rc e (k N ) Shear displacement (mm) TUD_ANC-CH0-13

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Figure 50 – Summary of the “Force-Displacement curves” for monotonic horizontal shear loading of concrete-floor-to-wall connections.

Table 19 – Summary of results for monotonic horizontal shear loading of concrete-floor-to-wall connections.

Specimen Peak force [kN] Displacement [mm]

TUD_ANC-CH0-12 1.43 43.64 TUD_ANC-CH0-13 1.32 60.09 Average 1.37 51.87 Standard deviation 0.07 11.63 Coefficient of variation 5.4% 22.4% 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 0 10 20 30 40 50 60 70 S h e ar f or ce ( k N ) Displacement (mm) TUD_ANC-CH0-12 TUD_ANC-CH0-13 Average

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Experimental results on TUD_ANC-CVz-i specimens (complete

connection – vertical shear loading)

Monotonic tests (TUD_ANC-CV0)

When the specimens are loaded in shear perpendicular to the mortar joints, the mortar cracks and fails, and the threaded bar bends. The tests were performed up to the couplet touching the concrete block.

Figure 51 – Failure for monotonic vertical shear loading of concrete-floor-to-wall connections. Figure 52, Figure 53 and Table 20 report the force-displacement curves for each single performed test and a summary of the results.

0 1 2 3 4 5 6 7 8 0 10 20 30 40 50 60 70 Shea r fo rce (k N ) Shear displacement (mm) TUD_ANC-CV0-01 0 1 2 3 4 5 6 7 8 0 10 20 30 40 50 60 70 Shea r fo rce (k N ) Shear displacement (mm) TUD_ANC-CV0-06 0 1 2 3 4 5 6 7 8 0 10 20 30 40 50 60 70 Shea r fo rce (k N ) Shear displacement (mm) TUD_ANC-CV0-07 0 1 2 3 4 5 6 7 8 0 10 20 30 40 50 60 70 Shea r fo rce (k N ) Shear displacement (mm) TUD_ANC-CV0-08

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Version 01 – Final 30/06/2017 Figure 52 – Force displacement curve for monotonic vertical shear loading of concrete-floor-to-wall

connections.

Figure 53 – Summary of the “Force-Displacement curves” for monotonic vertical shear loading of concrete-floor-to-wall connections.

Table 20 – Summary of results for monotonic vertical shear loading of concrete-floor-to-wall connections.

TUD_ANC-CV0-01 5.65 58.53* TUD_ANC-CV0-06 5.18 60.20* TUD_ANC-CV0-07 4.69 56.49 TUD_ANC-CV0-08 6.96 60.15* TUD_ANC-CV0-14 6.37 60.27* TUD_ANC-CV0-14 5.96 52.27 Average 5.80 57.99 Standard deviation 0.82 3.16 Coefficient of variation 14.1% 5.5%

* no failure of the specimen

0 1 2 3 4 5 6 7 8 0 10 20 30 40 50 60 70 Shea r fo rce (k N ) Shear displacement (mm) TUD_ANC-CV0-09 0 1 2 3 4 5 6 7 8 0 10 20 30 40 50 60 Shea r fo rce (k N ) Shear displacement (mm) TUD_ANC-CV0-14 0 1 2 3 4 5 6 7 8 0 10 20 30 40 50 60 70

S

h

e

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f

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[

k

N

]

Displacement [mm]

TUD_ANC-CV0-01 TUD_ANC-CV0-06 TUD_ANC-CV0-07 TUD_ANC-CV0-08 TUD_ANC-CV0-09 TUD_ANC-CV0-14 Average

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Cyclic tests – Protocol V1 (TUD_ANC-CV1)

When the complete specimens are tested according to Protocol V1, the mortar cracks and the threaded bar yield and break after separation of the couplet in two parts.

It should be noted that with monotonic loading the threaded bar at the same displacement has not failed yet. This suggested the introduction of Protocol V2.

Figure 54 – Failure for cyclic vertical shear loading of concrete-floor-to-wall connections (Protocol V1).

-2 0 2 4 6 8 -75 -50 -25 0 25 50 75 S h e a r fo rc e ( k N ) Shear displacement (mm) TUD_ANC-CV1-05 -2 0 2 4 6 8 -75 -50 -25 0 25 50 75 S h e a r fo rc e ( k N ) Shear displacement (mm) TUD_ANC-CV1-10 -2 0 2 4 6 8 -75 -50 -25 0 25 50 75 S h e a r fo rc e ( k N ) Shear displacement (mm) TUD_ANC-CV1-11 -2 0 2 4 6 8 -75 -50 -25 0 25 50 75 S h e a r fo rc e ( k N ) Shear displacement (mm) TUD_ANC-CV1-15

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Version 01 – Final 30/06/2017 Figure 55 – Force displacement curve for cyclic vertical shear loading of concrete-floor-to-wall connections

(Protocol V1).

Figure 56 – Summary of the envelope curves for cyclic vertical shear loading of concrete-floor-to-wall connections (Protocol V1).

Table 21 – Summary of results for cyclic vertical shear loading of concrete-floor-to-wall connections (Protocol V1).

TUD_ANC-CV1-05 5.57 59.11 TUD_ANC-CV1-10 6.74 59.75 TUD_ANC-CV1-11 5.75 59.81 TUD_ANC-CV1-15 6.21 54.64 TUD_ANC-CV1-16 8.39 57.60 TUD_ANC-CV1-17 7.36 57.38 Average 6.89 57.84 Standard deviation 1.03 2.12 Coefficient of variation 15% 4% -2 0 2 4 6 8 -75 -50 -25 0 25 50 75 S h e a r fo rc e ( k N ) Shear displacement (mm) TUD_ANC-CV1-16 -2 0 2 4 6 8 -75 -50 -25 0 25 50 75 S h e a r fo rc e ( k N ) Shear displacement (mm) TUD_ANC-CV1-17 -2 0 2 4 6 8 10 -75 -50 -25 0 25 50 75

S

h

e

ar

f

or

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[

k

N

]

Displacement [mm]

TUD_ANC-CV1-05 TUD_ANC-CV1-10 TUD_ANC-CV1-11 TUD_ANC-CV1-15 TUD_ANC-CV1-16 TUD_ANC-CV1-17 Average

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Cyclic tests – Protocol V2 (TUD_ANC-CV2)

The testing of the complete specimen according to protocol V2 was interrupted due to technical problems of the setup and only one test was performed. However, the results of that test are consistent with the results of the cyclic tests according to protocol V1 and therefore they are reported below.

At failure, the threaded bar yields and then breaks. The mortar and the couplet remain intact: nor cracks in the mortar joints nor interface detachment between the brick and the mortar were observed (Figure 57). Figure 58, Figure 59 and Table 22 report the force-displacement curves and a summary of the results.

Figure 57 – Failure for cyclic vertical shear loading of concrete-floor-to-wall connections (Protocol V2).

Figure 58 – Force displacement curve of concrete-floor-to-wall connections (Protocol V2). -0.5 0 0.5 1 1.5 2 -50 -25 0 25 50

S

h

ea

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fo

rc

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(k

N

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Shear displacement (mm)

TUD_ANC-CV2-18

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F

Figure 59 – Summary of the envelope curves for cyclic vertical shear loading of concrete-floor-to-wall connections (Protocol V2).

Table 22 – Summary of results for cyclic vertical shear loading of concrete-floor-to-wall connections (Protocol V2).

TUD_ANC-CV2-18

_1.57

_29.84

Average - - Standard deviation - - Coefficient of variation - - -0.5 0 0.5 1 1.5 2 -40 -30 -20 -10 0 10 20 30 40 S h ear f or ce [kN] Displacement [mm] TUD_ANC-CV2-18

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Summary of results

Table 23 reports the results obtained from the vertical shear loading of the complete specimens for different protocols.

Some differences can be noted:

- the peak forces of protocol V0 and protocol V1 are quite close (the cyclic loading leads to a 18.7% higher peak force at the same displacement), while protocol V3 leads to a peak force 72.9% lower than that of V0.

- The displacement capacity of the specimens is significantly different: the test was stopped for both protocols V0 and V1 at a displacement of about 60 mm when the masonry couplet was about to touch the concrete part. However, at that displacement the threaded bar was yield for monotonic loading, whereas it failed for a lightly smaller displacement (58 mm). Under cyclic protocol V2 the specimens fail at about the half displacement (~30mm).

- The difference between the peak force and the displacement of protocol V1 and protocol V2 is significant. However, the average dissipated energy for each protocol (area of hysteretic loops of specimens tested according to protocol V1 or protocol V2) is roughly the same for both the protocols (about 290 J): in fact the larger number of cycles with smaller amplitude (protocol V2) leads to the same amount of energy being dissipated until the failure of the specimen with that dissipated when smaller number of cycles with larger amplitude is applied (protocol V1).

- In general, the connection is able to transfer significant amount of shear loads (>0.5 kN) only after large displacements (>20 mm), showing an extremely low stiffness for cycles of small amplitude, which are those that usually characterize this typology of connection. This is mainly due to the presence of the polystyrene that allows a long debonded section of the threaded bar.

The performed tests show that the connection is not able to transfer any significant shear load for displacement coherent with the deformation of the structure (<20 mm). The connection can be therefore modelled as truss elements with nonlinear behaviour.

Table 23 – Average results for vertical shear loading of concrete-floor-to-wall connections according to the different protocols.

Protocol Peak vertical force [kN] Displacement [mm]

V0 (monotonic) 5.80 >60

V1 (cyclic – small number of cycles per phase) 6.89 57.8

V2 (cyclic – large number of cycles per phase) 1.57 29.8

(a) (b)

Figure 60 – Indicative hysteretic curves for vertical shear cyclic loading: (a) Protocol V1; (b) Protocol V2 -2 0 2 4 6 8 -75 -50 -25 0 25 50 75 S h e a r fo rc e ( k N ) Shear displacement (mm) -2 0 2 4 6 8 -75 -50 -25 0 25 50 75 S h e a r fo rc e ( k N ) Shear displacement (mm)

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References

[1] Messali, F. Esposito, R. (2016). Tests on anchorages: background document and testing protocol. Delft University of Technology. Report number C31B67WP6-1, version 03, 08 August 2016

[2] EN, B. (1999). 1015-3: 1999. Methods of test for mortar for masonry part 3: Determination of consistence of fresh mortar (by flow table).

[3] Esposito, R. Messali, F. Rots, J.G. (2016). Material characterization of replicated masonry and wall ties. Final report 18 April 2016, Delft University of Technology, Delft, the Netherlands.

[4] EN, B. (2012). 846-5: 2012 Methods of test for ancillary components for masonry—Determination of tensile and compressive load capacity and load displacement characteristics of wall ties (couplet test). [5] EN 1996-1-1+A1 (2013). Eurocode 6 – Design of masonry structures – Part 1-1: General rules for

reinforced and unreinforced masonry structures. Nederlands Normalisatie-instituit (NEN).

[6] Graziotti F, Magenes G (2016): Experimental campaign on cavity walls systems representative of the Groningen building stock, EUCENTRE Technical Report, 16 June 2016, Pavia, Italy

[7] Esposito R, Ravenshorst G (2016): Meeting TU Delft & ARUP on timber connection and strengthening methods for cavity walls, Minutes, 30 June 2016, Delft, the Netherlands

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Tests on existing floor to wall connections

Tests on existing floor to wall connections

Messali, F.; Skroumpelou, Georgia

Publication date

2017

Document Version

Final published version

Citation (APA)

Messali, F., & Skroumpelou, G. (2017). Tests on existing floor to wall connections. Delft University of

Technology.

Important note

To cite this publication, please use the final published version (if applicable).

Please check the document version above.

TU Delft Large-scale testing campaign 2016

TESTS ON EXISTING FLOOR TO WALL

CONNECTIONS

Authors: Francesco Messali, Georgia Skroumpelou

Table of Contents

1 Introduction

2 Construction of the specimens

3 Types of tests and specimens

Types of specimens

Name of the specimens

4 Axial tests on concrete floor specimens

Testing procedure

Experimental results on TUD_ANC-FN0-i specimens (concrete

blocks)

0

2

4

6

8

10

12

0

1

2

3

4

5

6

V

e

rt

ic

a

l

fo

rc

e

(

k

N

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Vertical displacement (mm)

5 Axial tests on calcium silicate masonry specimens

Testing procedure

Experimental results on TUD_ANC-WNz-i specimens

(CaSi masonry couplets – no washer)

F

or

ce

(

k

N

)

Displacement (mm)

Experimental

results

on

TUD_ANC-WSz-i

specimens

(CaSi masonry couplets – small washer)

Experimental

results

on

TUD_ANC-WBz-i

specimens

(CaSi masonry couplets – big washer)

F