Experimental Research on Interfacial Bond Performance in Rock Anchor with High-Performance Grouting Medium

2012 ◽  
Vol 517 ◽  
pp. 932-938 ◽  
Author(s):  
Zhi Fang ◽  
Hong Qiao Zhang

There exist the problems such as low bond strength and bad durability in the ordinary grouting slurry of the ground anchor system at present. The high-performance grouting mediums RPC (Reactive Powder Concrete) and DSP (Densified Systems containing homogeneously arranged ultrafine Particles) would become the potential replacement of grouting medium in ground anchor resulting from their high compressive strength, durability and toughness. Based on a series of pull-out tests on ground anchors with different high-performance grouting medium of RPC and DSP , different bond length in the construction field, the bond performance on the interfaces between anchor bolt (deformed steel bar) and grouted medium as well as between grouted medium and rock mass was studied. The results indicate that the interfacial bond strength between RPC or DSP and deformed steel bolt ranges within 23-31Mpa, far greater than that (about 2-3MPa) between the ordinary cementitious grout and deformed steel bar. Even though the interfacial bond strength between the grouted medium and rock mass of limestone was not obtained in the test since the failure mode was pull-out of those steel bar rather than the interface shear failure between grouted medium and rock mass, the bond stress on the interface reached 6.2-8.38 MPa, also far greater than the bond strength (about 0.1-3MPa) between the ordinary cementitious slurry and rocks.

2002 ◽  
Vol 11 (1) ◽  
pp. 096369350201100 ◽  
Author(s):  
J. M. Caceres ◽  
A. N. Netravali

The paper discusses a simple specimen geometry to obtain the fibre/cement interfacial shear strength (IFSS). The specimens are easy to prepare and easy to test. The technique gives reliable and reproducible results. IFSS results for five different fibres with cement were measured. Most IFSS values obtained are in the range of 0.15 to 1.5 MPa. Despite the simplicity of the technique presented in this study, the results are in agreement with those obtained by several other researchers using different techniques and specimen geometry.


1994 ◽  
Vol 370 ◽  
Author(s):  
N. Banthia ◽  
N. Yan ◽  
C. Chan ◽  
C. Yan ◽  
A. Bentur

AbstractBond-slip characteristics for steel micro-fibers bonded in cement-based matrices were investigated by conducting single fiber pull-out tests. The influence of the following factors was investigated: fiber inclination, fiber size, fiber embedded length and matrix refinement using silica fume. It was found that the bond-slip characteristics of fibers aligned with respect to the loading direction were necessarily superior than those inclined at an angle. Inclined fibers supported smaller peak pull-out loads and absorbed lesser pull-out energies than the aligned fibers. The use of silica fume in the matrix was found to improve both the average interfacial bond strength and the maximum interfacial bond strength between the fiber and the matrix.


2000 ◽  
Vol 9 (3) ◽  
pp. 096369350000900 ◽  
Author(s):  
E. Mδder ◽  
X.-F. Zhou ◽  
E. Pisanova ◽  
S. Zhandarov ◽  
S. R. Nutt

Interfacial bond strength between epoxy resin and glass fibre was studied using the pull-out and push-out techniques. For untreated fibres, these micromechanical tests gave similar values of the local interfacial shear strength and critical energy release rate. In the case of fibres treated by γ-APS, both tests showed considerable increase in the bond strength. However, for the modified fibres, the pull-out test gave greater values of both interfacial parameters than the push-out test, a result attributed to the different modes of interfacial loading. The different loading patterns also cause different failure mechanisms in these two tests.


2014 ◽  
Vol 919-921 ◽  
pp. 2061-2070
Author(s):  
Ya Fang Zhang ◽  
Pei Ran Chen ◽  
Hao Liu ◽  
Qing Hua Wu

The reinforcing and toughening effect of fiber reinforced concrete (FRC) are mainly under control of the interfacial bond strength in between of fiber and concrete, and the embedded length of fiber is one of the significant factors for interfacial bond strength. In this paper, pull-out numerical models based on single steel or polypropylene fiber have been studied with the fiber embedded length set as a variable and the influence of fiber embedded length on properties of single fiber pullout has, therefore, been analyzed. The results indicate that the longer the fiber embedded length, the larger the peak index and pull-out toughness of single fiber pull-out specimen could be reached, while the interfacial bond strength would decrease. The variation of fiber embedded length has only a little impact upon the damage process of pullout. Finally, the test results for specimen with the polypropylene fiber is more sensitive to the changes of embedded length compared those with steel fiber


2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Xiao Lei ◽  
Rui Wang ◽  
Hanwan Jiang ◽  
Faxiang Xie ◽  
Yanni Bao

High-strength concrete (HSC) is widely used in engineering due to its high strength and durability. However, because of its low water-to-cement ratio, external curing water hardly enters the dense internal structure of HSC so that high self-desiccation shrinkage often takes place. As a result, superabsorbent polymers (SAP) are added as an internal curing material to effectively reduce the shrinkage of high-performance concrete. Meanwhile, the bond performance between reinforcing steel and SAP HSC concrete remains unknown. In this paper, the bond performance of HSC mixed with SAP is studied by pull-out tests, and the results were obtained as follows: (1) the bond strength of HSC mixed with SAP increased first and then decreased with the increase of SAP content; (2) the slip at ultimate bond strength of HSC with SAP decreased with the increase of compressive strength; (3) a prediction model of the stress-slip relationship between steel rebars and HSC was established.


Sign in / Sign up

Export Citation Format

Share Document