scholarly journals Experimental investigation of bond between GFRP reinforcement and concrete using pull-out test

2018 ◽  
Author(s):  
Thanyawat Pothisiri ◽  
Pitcha Jongvivatsakul ◽  
Vanichapoom Nantavong

<p>The use of post‐installed rebars into existing reinforced concrete structures bonded with epoxy resins was constantly increasing due to the advantage of equivalent or even higher bearing capacities at service temperature, compared with conventional cast‐in‐place rebars. Previous studies have examined the effects of different parameters on the mechanical properties of bonded post‐installed rebars at normal temperature. These studies showed that, for rebar diameter equal to 10 mm, the load bearing capacity increases linearly with the embedment length up to 75 mm. However, upon exposure to high temperatures, the glass transition of epoxy resins may occur and affect the mechanical behaviour of the adhesive bond. Studying the mechanical behaviour of an adhesive anchor at high temperatures is therefore necessary. An experimental investigation is conducted herein to examine the characteristics of the adhesive bonding stress between steel rebar and concrete interface at elevated temperatures using a series of pull‐out tests with varying rebar diameters and embedment lengths.</p>


2019 ◽  
Vol 292 ◽  
pp. 217-223 ◽  
Author(s):  
Ondřej Janus ◽  
Frantisek Girgle ◽  
Vojtech Kostiha ◽  
Petr Štěpánek ◽  
Pavel Sulak

It is well-known that test configuration affects bond behaviour of steel reinforcement, but this effect has not yet been sufficiently quantified when using FRP reinforcement. This paper presents partial results from an ongoing experimental programme that deals with the bond strength of GFRP bars with concrete, with regards to the effect of the surface treatment of the rebars and test configuration. A modified beam test is presented in this study along with a pull-out test with an eccentric bar placement. The bond strength of GFRP reinforcement with sand-coated treatment using silica sand and ribbed type with milled ribs was tested. The sand-coated bars exhibit different bond behaviour compared to the ribbed ones due to different forces transfer from the reinforcement to the concrete. Thickness of the concrete cover layer also has a significant effect on the bond behaviour of the reinforcement.


2020 ◽  
Vol 11 (4) ◽  
pp. 114-118
Author(s):  
Robertas Zavalis ◽  
Bronius Jonaitis

The use of thin brick veneer layers for building facades becomes more popular nowadays. Using thin bricks (50−65 mm thick) instead of normal 100−120 mm thick bricks let us to save expenses up to 50% related to materials. The connection of thin veneer layer with inner construction wall must be assured. Usually, the connection is fulfilled using flexible metal or composite ties. The main issue for this connection is tie pull out strength from thin brick masonry. This strength depends on type and construction of ties and it governs the number of ties need for facades. This article describes experimental research of pull out strength of flexible steel ties in thin brick masonry. Two possible anchoring types were used. Experimental test results and analysis are described in the article.


2021 ◽  
Author(s):  
Alireza Abolghasem

This study aims at providing research information on the pullout capacity of straight and headed-end GFRP bars embedded in bridge deck slab as pre-installed anchors for new bridge barrier-deck construction and as post-installed anchors for the replacement of deteriorated bridge barriers. In Phase I of this research, the pullout capacity of pre-installed ribbed-surface GFRP bars in twin- and triple-bar groups were investigated experimentally, considering different bar size, spacing and embedment depths. In phase II of this research, the pullout capacity of post-installed sand-coated and ribbed-surface GFRP bars were investigated experimentally considering different bar size and embedment depths and adhesive types. The experimental findings were compared with available experimental results and pullout formulas. Design values for the pullout strength of the GFRP bars as pre- and post-installed anchors in concrete were deduced.


2014 ◽  
Vol 15 ◽  
pp. 01031 ◽  
Author(s):  
M.A. Othuman Mydin ◽  
N. Noordin ◽  
Z. Matori ◽  
N. Md Sani ◽  
N.F. Zahari

Author(s):  
A. N. Shuaib ◽  
N. Merah ◽  
M. Ahmed ◽  
Y. N. Al-Nassar ◽  
S. S. Al-Anizi

This paper presents the results of an experimental investigation conducted to evaluate the effect of initial tube-tubesheet diametral clearance on the integrity of roller expanded tube-to-tubesheet joints in over enlarged tubesheet holes. The criteria of evaluating joint integrity include the pull out force and hydraulic tightness of the joints in which tubes were expanded to 5% wall reduction after metal to metal contact of the tube with the tubesheet hole. The levels of clearance investigated were selected to cover a range that exceeded by ten times that prescribed by the Tubular Exchangers Manufacturers Association (TEMA) standards [1]. The pull out test results showed that, within the investigated range of clearance, the joint strength has not declined below the strength of joints with clearance levels within the TEMA range. In fact the pull out force exhibited a slight linear increasing trend with the increase in initial clearance, which is attributed to the effect of tube strain hardening. The hydro test results indicated that all joints within the investigated clearance levels were hydraulically tight when they were tested at 1.5 times the design pressure of the heat exchanger for duration of 30 minutes. A relationship between rolling specific energy and initial joint clearance has been developed.


2019 ◽  
Vol 89 (21-22) ◽  
pp. 4717-4731 ◽  
Author(s):  
Zhou Yi ◽  
Muhammad Ali ◽  
Xiaozhou Gong ◽  
Hanming Dai ◽  
Deng Zhongmin

Yarn–yarn sliding force plays a vital role in absorbing impact energy for plain fabrics. This paper reports the methods and results of an investigation on the mechanisms that enable higher yarn pull-out force of woven fabrics with the incorporation of lenos and knits. The experimental results suggested that the insertion of leno lines on plain weave gives an approximately 20% increase in junction rupture force over the original plain construction. With knitted structures inserted, the structure-modified fabrics showed a junction rupture force up to about 15 times higher than simple plain weave. It was even found that the yarns failed rather than pulled out in multiple yarn pull-out tests. This is because knitted structures tend to become self-locked and consequently restrict yarn displacement when subjected to external loading. This investigation reports a method to increase the frictional force between the warp and weft yarns based on textile technologies. It is expected that the results obtained could provide some useful information for the engineering design of flexible ballistic protection systems.


Buildings ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 155
Author(s):  
Robert Studziński ◽  
Katarzyna Ciesielczyk

In this paper, we present an original experimental investigation on a pull-out test of a blind rivet from the external facing of sandwich panels with various core layer materials (polyisocyanurate foam, mineral wool, and expanded polystyrene). The blind rivets were subjected to an axial and eccentric tensile force introduced as static and quasi-cyclic loading. The statistical sample size was 5. The laboratory results depicted that the core layer of a sandwich panel influenced the load-displacement path of the investigated blind rivet connections, regardless of the nature of the load (static, quasi-cyclic) and the point of the load application (axial, eccentric). It was observed that the blind connection with the polyisocyanurate foam core sandwich panel was characterized by a reduction of both the capacity and the secant stiffness when compared with the blind connection with the mineral wool or the expanded polystyrene core sandwich panels. Moreover, the tested connections demonstrated that the eccentric load gave a higher flexural stiffness than the axial load and that the quasi-cyclic load did not reduce their stiffness and capacity.


2015 ◽  
Vol 68 ◽  
pp. 215-229 ◽  
Author(s):  
Gaurav Nilakantan ◽  
Richard L. Merrill ◽  
Michael Keefe ◽  
John W. Gillespie ◽  
Eric D. Wetzel

Sign in / Sign up

Export Citation Format

Share Document