Resistance of the cement-aggregate interfacial zone to the propagation of cracks

Saito, Mitsuro; Kawamura, Mitsunori

doi:10.1016/0008-8846(86)90038-4

Cited by 24 publications

(6 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At a macroscopic scale, the direct tensile tests on concrete are difficult to achieve and often show widely dispersed results [25]. Several kinds of tensile tests are used to measure the tensile strength of the concrete, such as the splitting test or the threepoint bending test.…”

Section: Direct Tensile Testmentioning

confidence: 99%

Experimental characterization of mechanical properties of the cement-aggregate interface in concrete

Jebli

Jamin

Malachanne

et al. 2018

Construction and Building Materials

View full text Add to dashboard Cite

The microstructure of the Interfacial Transition Zone (ITZ) between the aggregates and the cement paste is characterized by a higher porosity than that of the bulk paste. The particular properties of this zone strongly influence the mechanical behavior of concrete. Microscopic cracks, which develop during subsequent loading, appear either in the matrix (cement paste or mortar) or along the cement-aggregates interface. Cracks could be caused by either tensile, shear strengths or by combinations of both. In this work, the mechanical properties of the cement paste-aggregate sample are experimentally studied. The experimental tests are performed on parallelepipedic samples at classical aggregate scale (one centimeter sections). These samples are composed of limestone aggregates and Portland cement paste, hereafter named ''composite". The cement paste is prepared with a water/cement ratio of 0.5. The shape of the prepared composites makes them convenient for direct tensile and shear tests. At different stages of hydration, we performed direct tensile and shear tests on the composites by means of specific devices. The same tests were carried out on the cement paste in order to compare with the composite results. The analysis of the experimental results showed that the tensile strength of the cement-aggregate interface was about 30% lower than that of the cement paste tensile strength. Also, the shear strength of the cement-aggregate interface was smaller than the shear strength of the cement paste. In the same way as macroscopic Mohr-Coulomb criterion, we observed an increase of shear strength when normal stress increased. It provides access to a local cohesion (c) and a local friction angle ðUÞ at classical aggregate scale.

show abstract

Section: Direct Tensile Testmentioning

confidence: 99%

Experimental characterization of mechanical properties of the cement-aggregate interface in concrete

Jebli

Jamin

Malachanne

et al. 2018

Construction and Building Materials

View full text Add to dashboard Cite

show abstract

“…It was possible to expect a chemical reaction between the aggregate in concrete and the silica fume matrix, resulting in high fracture energy with smooth hardened concrete surface. The interaction between cement paste and aggregate surface lowers both the toughness and the cracking resistance at the interface (Saito & Kawamura 1986). On casting surface of hardened concrete, cement paste could penetrate into the voids to improve the mechanical interlock.…”

Section: 1cmentioning

confidence: 97%

“…A chemical reaction of cement paste with limestone and andesitic aggregates can raise the micro-hardness and can reduce the crack resistance. Such interface exhibits low toughness, and with the addition of silica fume, its toughness increases (Saito & Kawamura 1986).…”

Section: Review Of Literaturementioning

confidence: 98%

Influence of interface properties on fracture behaviour of concrete

Rao

Prasad

2011

Sadhana

View full text Add to dashboard Cite

Hardened concrete is a three-phase composite consisting of cement paste, aggregate and interface between cement paste and aggregate. The interface in concrete plays a key role on the overall performance of concrete. The interface properties such as deformation, strength, fracture energy, stress intensity and its influence on stiffness and ductility of concrete have been investigated. The effect of composition of cement, surface characteristics of aggregate and type of loading have been studied. The load-deflection response is linear showing that the linear elastic fracture mechanics (LEFM) is applicable to characterize interface. The crack deformation increases with large rough aggregate surfaces. The strength of interface increases with the richness of concrete mix. The interface fracture energy increases as the roughness of the aggregate surface increases. The interface energy under mode II loading increases with the orientation of aggregate surface with the direction of loading. The chemical reaction between smooth aggregate surface and the cement paste seems to improve the interface energy. The ductility of concrete decreases as the surface area of the strong interface increases. The fracture toughness (stress intensity factor) of the interface seems to be very low, compared with hardened cement paste, mortar and concrete.

show abstract

“…For such aggregates improved mechanical interlocking is dominant giving better bond strengths. Saito and Kawamura [10] reported that a chemical reaction in the vicinity of the interface between rock surfaces and cement paste takes place in the case of limestone and andesite, which results in raising the microhardness and reducing crack resistance. It seems that any chemical reaction between cement paste and rock surface lowers the cracking resistance of the interface.…”

Section: Previous Researchmentioning

confidence: 99%

“…The load levels seem to be relatively low in the interface. With the incorporation of silica fume, the interfacial fracture energy increases considerably [ 10].…”

Section: Previous Researchmentioning

confidence: 99%

Influence of type of aggregate and surface roughness on the interface fracture properties

Rao

Prasad

2004

Mat. Struct.

View full text Add to dashboard Cite

An experimental investigation of interface fracture in high strength concrete is reported. An attempt has been made to study the influence of strength of mortar, type of aggregate and its roughness on interface fracture properties. The parameters include load-CMOD variations, tensile strength, and fracture energy of the interface. Stiffness, compliance and ductility factors of the composite specimens have been evaluated in Mode-I loading. The fracture energy increases as the roughness of the aggregate surface increases. The stiffness of the composite specimen increases as the roughness of the aggregate surface increases. The ductility factor (i.e. the fracture energy per unit of peak load) decreases as the surface area of the interface increases in sandwiched composite specimens in Mode-I failure, whereas it increases with the interface area in composite specimens with mortar cast against rough concrete aggregates. The interface exhibits brittle behavior with catastrophic failure indicating the application of LEFM to the interface.

show abstract

Resistance of the cement-aggregate interfacial zone to the propagation of cracks

Cited by 24 publications

References 5 publications

Experimental characterization of mechanical properties of the cement-aggregate interface in concrete

Experimental characterization of mechanical properties of the cement-aggregate interface in concrete

Influence of interface properties on fracture behaviour of concrete

Influence of type of aggregate and surface roughness on the interface fracture properties

Contact Info

Product

Resources

About