Adhesive Mortars Research Articles

Atık Mermer Tozlarının Seramik Yapıştırma Harcı Olarak Değerlendirilmesi

Atık Mermer Tozlarının Seramik Yapıştırma Harcı Olarak Değerlendirilmesi

Investigation on the usage of waste marble powder in cement-based adhesive mortar

In this study, the availability of marble powder (MP) additive at different ratios were investigated instead of dolomite, which is the raw material in adhesive mortars of insulation board. Marble waste powder’s humidity, chemical structure and particle size was investigated. Then, compressive – tensile – bending strengths, water absorption, initial setting time, and flow-spreading tests at the adhesive mortars with additive were performed. All results showed that marble waste powder’s humidity was lower than 1%, and particle size amounts +710µm and −125µm were more than raw dolomite. As a result of the tests, it was determined that the values were obtained in accordance with the relevant EN standards. According to the results of XRD, the ratio of calcium carbonate and hatrurite ratio of marble powder are exceeded. The use of marble powder with dolomite was also investigated economically and it was concluded that it is more advantageous to make cost calculations.

Modeling Adhesive Anchors in a Discrete Element Framework

In recent years, post-installed anchors are widely used to connect structural members and to fix appliances to load-bearing elements. A bonded anchor typically denotes a threaded bar placed into a borehole filled with adhesive mortar. The high complexity of the problem, owing to the multiple materials and failure mechanisms involved, requires a numerical support for the experimental investigation. A reliable model able to reproduce a system’s short-term behavior is needed before the development of a more complex framework for the subsequent investigation of the lifetime of fasteners subjected to various deterioration processes can commence. The focus of this contribution is the development and validation of such a model for bonded anchors under pure tension load. Compression, modulus, fracture and splitting tests are performed on standard concrete specimens. These serve for the calibration and validation of the concrete constitutive model. The behavior of the adhesive mortar layer is modeled with a stress-slip law, calibrated on a set of confined pull-out tests. The model validation is performed on tests with different configurations comparing load-displacement curves, crack patterns and concrete cone shapes. A model sensitivity analysis and the evaluation of the bond stress and slippage along the anchor complete the study.

The Effect of Interface Agent on Bonding Strength between Rock Wool Belt and Adhesive Mortar

Rock wool belt is one form of rock wool products used in external thermal insulation composite system. However, a related and important problem is how to improve bonding strength between rock wool belt and adhesive mortar. The present work studies the effect of interface agent on bonding strength. After interface agent was applied on the surface of rock wool belt, the original strength and water-resistance strength increased remarkably with the increasing of the concentration of interface agent, and the maximum value was almost 7 times over that without interface agent. It was believed that the significant increasing of bonding strength was related to fiber structure of rock wool belt, correspondingly, the interface agent could improve effective bonding area and increase the bonding depth. Moreover, it is worth noticing that the drying time of the interface agent had little effect on original strength and water-resistance strength, so it needn't a strict time requirement for rock wool bonding construction after applying interface agent.

Research on Waste FRP Fiber Reinforced Adhesive Mortar

The use of FRP in industry results in large amount of waste FRP. If not treated properly, it will pollute the environment. In our study, waste FRP powder was used in mortar to substitute part of sand in mortar. The use of short waste FRP fibre can further increase the mechanical strength. The Waste FRP fibre reinforced adhesive mortar was prepared with the material proportioning: cement-sand ratio 1:2, polymer 8% (cement based ), waste FRP fibre 3% (based on the total solids ). The performance of the mortar conforms to JCT 547-2005 with excellent adhesive characteristics.

La ceniza de cascarilla de arroz y su efecto en adhesivos tipo mortero

En este estudio se presenta una caracterización de la ceniza de cascarilla de arroz a un tamaño de partícula adecuado para su desempeño como agregado fino en adhesivos tipo mortero para colocación de baldosas cerámicas, debido al alto porcentaje de sílice en su composición química. Se analizan las propiedades físicas y químicas de los agregados y el comportamiento mecánico de fluidez y resistencia a la tracción de los morteros obtenidos con reemplazo parcial de arena en porcentajes desde 5% hasta 25%, proponiendo así el empleo de los residuos de ceniza de cascarilla de arroz y presentando una alternativa de disminución a la explotación de arena, la cual genera impactos graves al medio ambiente. Los resultados muestran que un porcentaje de reemplazo de la arena por ceniza de cascarilla de arroz de 20% produce fuerzas de tracción comparables con las obtenidas para adhesivos comerciales.

Mortar modified with sulfonated polystyrene produced from waste plastic cups

Abstract In this work, we studied the addition of sulfonated polystyrene produced from waste plastic cups as an admixture for mortars. Mortars were analyzed with polystyrene content of 0.0; 0.2; 0.6; 1.0 and 1.4% in relation to the cement mass. The influence of polystyrene on the mortars' properties was evaluated by the consistency index, water retention, water absorption, porosity, elasticity modulus, compressive strength, flexural strength, bond tensile strength and microscopy. The increase in the sulfonated polystyrene content decreased the elasticity modulus of the mortar and, despite higher porosity, there was a reduction of water absorption by capillarity. In relation to mortar without admixture, the modified mortar showed an increase in water retention and consistency index, and a large increase in flexural strength and bond tensile strength. The significant increase of bond tensile strength (214% with admixture 1%) highlights the potential of the produced material as an adhesive mortar.

Water Vapour Resistance Factors of Three Wall Surface Finishing

There are results of water vapour resistance factors of three compositions commonly used for wall finishing in the paper. The compositions are: basic adhesive diffusion mortar; basic adhesive diffusion mortar with silicate plaster; basic adhesive diffusion mortar with acrylic plaster. There are not only the results of water vapour resistance factors but there are also the discussions as well as the impacts of the border conditions, it means temperature, relative humidity and barometric air pressure in the paper.

寒冷地に10年間屋外暴露されたタイル張りの耐久性評価

We made specimens for tile facing using light-weight adhesive mortars. In a cold region (Kushiro city, Hokkaido), after 10 years outdoor exposure tests, we estimated the durability evaluation. Specimens for external wall didn’t degrade to adhesive strength. Small size specimens degraded to adhesive strength, exposed to rain has caused strength degradation. On the other hand, Light-weight adhesive mortars didn’t catch the frost damage.

Adherence of Granite Plates by Mortar Adhesion: Influence of Temperature

The objective of this work was to study the effect of temperature variation on the adherence of granite plates fixed with adhesive mortars on external flooring and exterior cladding. The rock selected was a commercially well accepted syenogranite, known as Vermelho Capao Bonito, which has excellent technological qualities and high aesthetic value. Tensile bond strength and pullout tests were performed according to the techniques proposed for ceramic materials, in view of the lack of standards for dimension stones. The test specimens were set on standard substrates with two types of mortars, one commercially manufactured by a leader company and the other developed in laboratory. After normal curing conditions (28 days at 23°C and relative humidity of 65%), the adhesion tests were performed at the following temperatures: 23oC, 30°C, 40°C, 50°C and 60°C. With increasing temperature the results indicated a decrease in adhesion values of 48% to 42%, from 2.04 to 1.13 MPa for the one developed in the laboratory and from 1.92 to 1.12 MPa for the commercial mortar. The behavior of the microstructure on the standard substrate-mortar-rock interfaces were also investigated by optical microscopy, and no signs of reaction or penetration of mortars into the rock (anchoring) were observed. With regard to the adhesion values, temperature variation was an important factor to its decrease, offering important perspectives for new experiments with other types of granites, for studies of displacements and pathologies commonly observed in external cladding made with plates of these materials.

Diffusion Parameters of Basic Diffusion Adhesive Mortars with Silicate or Acrylic Plaster

The paper summarizes the results of water vapour resistance factors of three commonly used compositions for wall finishing (basic adhesive diffusion mortar; basic adhesive diffusion mortar + silicate plaster; basic adhesive diffusion mortar + acrylic plaster). The border conditions of the measuring (temperature, relative humidity and barometric air pressure) and their impacts on the results are discussed as well.

Pore structure of mortars with cellulose ether additions – Study of the air-void structure

Polished section analysis was employed to study the pore structure of model tile adhesive mortars containing different types of cellulose ethers (CE, respectively Methyl Cellulose, Hydroxyethyl- and Hydroxypropyl-Methyl Cellulose) at different dosages (0.3% and 0.8% by dry mortar mass). Flat layers of hardened mortar applied on an absorbing substrate were studied. To enhance the visibility of the air voids, the polished cross-sections were colored in black and talcum powder was pressed into the voids. Next, flatbed scanner was used to take the images. Due to a high level of agglomeration of pores, digital detachment was necessary in order to retrieve their original shapes and sizes. A stereological reconstruction of 3-D pore size distributions was performed based on the 2-D data from section analysis. Pore shapes were analyzed by determining circularity of the 2-D pore representations, a parameter that allowed estimating the extent of pores agglomeration that occurred in the analyzed mortars. It was found that higher dosage of CE resulted in a slight volume increase and a clear coarsening of the air voids. As shown by the analysis of circularity, this is likely due to higher extent of agglomeration at higher CE dosage.

Adhesive mortars for stone plate bonding

This work addressed the properties of adhesive mortars and the comparative study of their use for stone plate bonding. Tests were performed on the tiles of eight types of “granites” to compare the adherence of well-known mortar brands on the market, specifically for granites. Thus, an adhesive porcelain mortar (with comparable production cost) was used, developed by researchers at the Institute of Architecture and Urbanism–University of Sao Paulo, in addition to three laboratory-developed porcelain-based mortars. The rocks chosen were: grey swallow (monzogranite), yellow ornamental (garnet porphyroblastic gneiss), red Brasilia (syenogranite), Black Sao Gabriel (hypersthene diorite), green labrador (charnoquite), fantastic blue (biotite monzogranite megaporphyritic serial gnaissified), black Indian (migmatite), and rose jacaranda (nebulitic migmatite syenogranite) They did not have similar petrographic and sawability characteristics that resulted in different initial roughness values of the plates obtained by breaking apart the blocks on the gangsaw machine. The machine used granulated steel as an abrasive element. The adherence of these rocks with the mortars was determined on the rough surface by the pullout traction test, standardized for ceramics. It was observed that the laboratory-developed mortars showed excellent adherence and flexibility qualities; larger contact surfaces provided greater physical interaction, since the extremely low porosity of the rocks under study limited the anchoring adhesion process (penetration of mortar through the pores).

Post‐installed reinforcement connections at ultimate and serviceability limit states

AbstractWhen reinforcing bars are post‐installed in holes drilled in cured concrete, adhesive mortars are used to create a bond between concrete and bars. Appropriate adhesives can develop higher bond strengths than standard ribbed bars cast into concrete. A detailed design concept for the anchorage length of reinforcing bars has been developed by taking into account splitting/spalling of the concrete and pullout. Pullout and splitting tests on reinforcing bars set in concrete were carried out with different adhesive mortars and with varying concrete strengths and concrete covers. When higher bond strengths than those recommended for cast‐in reinforcement are taken into account, it is important to check deformations and crack widths at the serviceability limit state (SLS) separately. For this reason, structural tests on slabs and corbels were carried out. Moreover, pullout tests on post‐installed reinforcing bars were performed in order to measure displacements at service load level.

Test and prediction of chloride diffusion in recycled aggregate concrete

Recycled aggregate concrete (RAC) specimens with different recycled coarse aggregate replacement ratios by mass (R) are fully immersed in a 10% chloride solution for 235 days. Both free chloride concentration (C f ) and total chloride concentration (C t ) are then measured employing a rapid chloride test (RCT) system. The Fick’s second diffusion law is verified by the test data and used to predict chloride concentration distribution at different immersion periods. Additionally, pore structures of the new and old mortar in RAC are tested by mercury intrusion porosimetry (MIP). It is found that binding chloride concentration (C b ) linearly increases with C f . In natural aggregate concrete (NAC), C f is obviously smaller than that in the RAC in the same testing environment and this is different from the test results of C t and C b . Furthermore, the effects of R on the chloride concentration of RAC become severe for specimens subjected to long immersion periods, which can be explained in terms of the pore structures of the new mortar and old adhesive mortar in RAC.

Pore structure of mortars with cellulose ether additions – Mercury intrusion porosimetry study

In this study, multi-cycle mercury intrusion porosimetry (MIP) was employed to study the pore structure of model tile adhesive mortars containing different types (Methyl Cellulose, Hydroxyethyl- and Hydroxypropyl-Methyl Cellulose) and different dosages (0.3%, 0.8%) of cellulose ethers (CE). The two cycles of mercury intrusion and extrusion allowed resolving not only the total porosity of the mortar, but also the interconnected porosity of the matrix. Different application scenarios were tested: application on a substrate with no water absorption (plastic mold), on a moderately absorbing substrate (cement–fiber board) and on a substrate with high absorption (concrete slabs). These conditions allowed for determining the influence of different moisture regimes on the pore structure of the mortars. Finally, tensile adhesion strength tests with different open times were performed. It was observed that the addition of CE did not considerably affect the capillary and gel pores of the matrix. At the same time, it led to a substantial increase of the total porosity due to the entrainment of air, with slightly increasing size of entrained air voids at higher CE addition rates. A very pronounced coarsening of the porosity could be observed when mortars where applied on a substrate with high water absorption. An improvement in tensile adhesion strength respect to the reference mortar was observed thanks to CE addition, in particular for longer open times.

Preparation of a new polymer-modified adhesive mortar using fine iron tailings as aggregate

In this paper, a new polymer-modified adhesive mortar is prepared using the fine iron tailings, eco-cement, redispersible latex powder, additives, and water. In our study, the fine iron tailings are used to replace the natural river sand as the mortar aggregate and the optimal process conditions are determined by the orthogonal experiment. The obtained results are shown as follows: The ratios of cement–sand and polymer–cement are 1:2.5 and 4%, respectively, with the aggregate modulus 0.81 and water reducing agent 0.5% (cement-based). The properties of the polymer-modified adhesive mortar obtained under the optimal process conditions conform to JC/T 547-2005 (China Professional Standard: Ceramic Tile Adhesive). Moreover, the microstructure of the polymer-modified adhesive mortar is studied and discussed. The results show that the network formed by the intertwined polymer film can prevent the merger of micro-cracks and improve the adhesive mortars’ overall cohesion. Therefore, adding polymer to the adhesive mortar can improve its failure stress and enhance its bonding strength.

Effects of Joint Thickness, Adhesion and Web Shells to the Face Shell Bedded Concrete Masonry Loaded in Compression

The Australian masonry standard allows either prism tests or correction factors based on the block height and mortar thickness to evaluate masonry compressive strength. The correction factor helps the taller units with conventional 10 mm mortar being not disadvantaged due to size effect. In recent times, 2–4 mm thick, high-adhesive mortars and H blocks with only the mid-web shell are used in masonry construction. H blocks and thinner and higher adhesive mortars have renewed interest of the compression behaviour of hollow concrete masonry and hence is revisited in this paper. This paper presents an experimental study carried out to examine the effects of the thickness of mortar joints, the type of mortar adhesives and the presence of web shells in the hollow concrete masonry prisms under axial compression. A non-contact digital image correlation technique was used to measure the deformation of the prisms and was found adequate for the determination of strain field of the loaded face shells subjected to axial compression. It is found that the absence of end web shells lowers the compressive strength and stiffness of the prisms and the thinner and higher adhesive mortars increase the compressive strength and stiffness, while lowering the Poissons ratio

Effects of joint thickness, adhesion and web shells to the face shell bedded concrete masonry loaded in compression

The Australian masonry standard allows either prism tests or correction factors based on the block height and mortar thickness to evaluate masonry compressive strength. The correction factor helps the taller units with conventional 10 mm mortar being not disadvantaged due to size effect. In recent times, 2-4 mm thick, high-adhesive mortars and H blocks with only the mid-web shell are used in masonry construction. H blocks and thinner and higher adhesive mortars have renewed interest of the compression behaviour of hollow concrete masonry and hence is revisited in this paper. This paper presents an experimental study carried out to examine the effects of the thickness of mortar joints, the type of mortar adhesives and the presence of web shells in the hollow concrete masonry prisms under axial compression. A non-contact digital image correlation technique was used to measure the deformation of the prisms and was found adequate for the determination of strain field of the loaded face shells subjected to axial compression. It is found that the absence of end web shells lowers the compressive strength and stiffness of the prisms and the thinner and higher adhesive mortars increase the compressive strength and stiffness, while lowering the Poisson's ratio.

Study on the Application of Puffing Glutinous Rice Starch

The puffing glutinous rice starch (PGRS) could be obtained by adding glutinous broken rice into bulking machine and expanding at a certain temperature and pressure. Compared with gelatinization by heating and adding alkali, gelatinization by puffing was easier to control and had a higher degree of starch gelation. The starch granule disintegrated after puffing and therefore more hydrophilic hydroxyls were exposed. The water-solubility of PGRS was increased which was shown in IR spectrometry with a broad and strengthened peak of O-H stretching vibration. Scanning electron micrograph (SEM) found that the PGRS granules were in shape of rough surface, which would be a strong affinity for water. Therefore, it could be used to prepare corrugated cardboard case adhesive, stamp envelope adhesive, wallpaper adhesive and dry mortar internal wall paint.