Prediction of compression strength of ancient mortars through in situ drilling resistance technique

Monte, Emanuele Del; Boschi, Sonia; Vignoli, Andrea

doi:10.1016/j.conbuildmat.2019.117563

Cited by 22 publications

(5 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…There are several methods [ 25 , 31 , 32 , 33 ] similar to PT that are currently being used for mortar diagnostic, e.g., “Sphere impact”, “controlled penetration” or “DRMS” (based on microdrilling resistance technique and is a modification of older PNT-G test [ 34 ]). Moreover, new methods, such as the “gun penetrometer”, are still under development [ 28 ].…”

Section: Minor-destructive Testing Methodsmentioning

confidence: 99%

Prediction of Mortar Compressive Strength Based on Modern Minor-Destructive Tests

Łątka

2023

Materials

View full text Add to dashboard Cite

The crucial task of the diagnosis of an existing masonry structure is to assess the current values of the mechanical parameters of the materials from which the structure was erected—usually bricks and mortar. The article presents the results of minor-destructive tests carried out on bed joints of three-brick-masonry prisms prepared in the laboratory. Three types of mortars used in the masonry were tested, which differ by the type and amount of binder. In order to determine mortar compression strength, three modern diagnostic methods were used: double punch test (DPT), standard penetrometric test (PT) and torque penetrometric test (TPT). Tests were carried out after 4, 12 and 90 weeks. The mortar strength determined in each of these tests was compared with the mortar reference strength determined on the beam specimen according to the methodology given in EN 1015-11. The results of the conducted tests confirmed the high usefulness of all three diagnostic methods. However, limitations in the application of the PT test were noticed—only lime mortars and weak cement–lime mortars can be tested with this method. In the case of mortars with an increased amount of cement binder, the impact energy is too low to estimate the compressive strength of the mortar in the brick wall joint. Technical limitations in the use of TPT and DPT tests were also indicated—weak lime mortars with low cohesion do not allow for obtaining reliable results. It was shown that DPT results strongly depend on two factors, specimen slenderness and mortar strength. Due to this fact, simple non-parameter conversion from mortar compressive strength according to the DPT test into mortar reference strength may lead to significant overestimation. As the results show, in newly built masonry, proper selection of diagnostic method is crucial due to the strong dependence of mortar curing dynamics on its location in the joint. This paper helps to match diagnostic techniques with the condition and type of mortar in the existing structure.

show abstract

Section: Minor-destructive Testing Methodsmentioning

confidence: 99%

Prediction of Mortar Compressive Strength Based on Modern Minor-Destructive Tests

Łątka

2023

Materials

View full text Add to dashboard Cite

show abstract

“…Results were considered to be outliers if it differed more than one and a half time the interquartile range (IQR) below the first quartile (25 percentile, Q1), or above the third quartile (75 percentile, Q3), a procedure described e.g. in [41]. IQR is the difference between Q3 and Q1.…”

Section: Statistical Treatment Of Datamentioning

confidence: 99%

Locally Produced UHPC: The Influence of Type and Content of Steel Fibres

Larsen

Thorstensen

2021

Nordic Concrete Research

View full text Add to dashboard Cite

Ultra-high performance concrete might be a competitive alternative to normal concrete for some purposes. But despite research efforts during decades, utilisation is still not widespread. Reasons include limited competence and material availability. This paper presents one step of a research initiative aimed at facilitating the use of UHPC in Norway. The step presented here comprises the accumulated results from investigations on the influence steel fibres (content, type, and hybrid combination) have on material strength and deformation behaviour of locally produced UHPC, made with constituents found in southern Norway. 231 specimens were tested, spanning nine UHPC mixes. Digital Image Correlation (DIC) was successfully used to study crack propagation. Compressive strength of 166 MPa and E-modulus of 46 GPa were obtained, not being influenced by fibre content. The flexural tensile strength was found to be strongly dependent on variations in steel fibre properties and mix design. The highest flexural tensile strength was obtained for prisms with micro straight steel fibres alone, or in 50% combination with macro hooked-end fibres. The experimental results are considered in a theory-informed discussion. Suggestions are made on the use of steel fibres in locally produced UHPC, potentially lowering the cost by 30%.

show abstract

“…Based on this limitation, some scholars suggest using non-destructive testing (NDT). There are records in the literature on the estimation of the mortar compressive strength through in-situ NDT methods, such as rebound hammer [1], penetration testing method [2], pendulum rebound hardness [3], and torque penetration testing method [4], equal point hardness tester [5], anti-drilling technology [6], indentation testing equipment [7], and scratch testing [8]. These methods are applicable to architectural heritage because of minimal damage to mortar and more testing data.…”

Section: Introductionmentioning

confidence: 99%

Estimation of in-situ Masonry Mortar Compressive Strength Using Pendulum Hamming Test Method

suhang,

Hu,

2024

Preprint

View full text Add to dashboard Cite

The compressive strength of in-situ masonry mortar was evaluated using the Pendulum Test Method (PHTM). A portable PHTM apparatus specifically designed for this purpose is utilized to indirectly evaluate the compressive strength by inserting steel nails into the horizontal mortar joints of the masonry and measuring the penetration depth. This apparatus can directly test extracted mortar samples without excessive preparation. The discrete attributes of the test outcomes are analyzed to ascertain the repeatability and reliability of the PHTM results. A relationship between penetration depth and compressive strength is established. In comparison with other existing testing methods, it has been confirmed that PHTM is an alternative compression testing method for masonry mortar, with the advantages of high accuracy, minimal preparation work, and good repeatability. The mortar compressive strength estimated by PHTM is reasonably consistent with the mortar cubic compressive strength test results.

show abstract

Prediction of compression strength of ancient mortars through in situ drilling resistance technique

Cited by 22 publications

References 28 publications

Prediction of Mortar Compressive Strength Based on Modern Minor-Destructive Tests

Prediction of Mortar Compressive Strength Based on Modern Minor-Destructive Tests

Locally Produced UHPC: The Influence of Type and Content of Steel Fibres

Estimation of in-situ Masonry Mortar Compressive Strength Using Pendulum Hamming Test Method

Contact Info

Product

Resources

About