Epoxy Grout Research Articles

Mechanism of healing, strength, and durability concepts of bacteria concrete - a review

Abstract Research work is going on to explore the concept of self-healing concrete. Outcome of the investigation reveals potential of bacteria concrete. Self-healing capacity imparted to the concrete by incorporating bacteria. Traditional methods reported in the literature such as epoxy injection, grouting, drilling, and plugging and gravity filling method have environmental impact, require more maintenance and are time consuming. The self-healing mechanism can be a better alternative to compensate these defects due to ecofriendly nature. Self-healing mechanism involves the production of CaCO3 precipitate deposites in crack region. Review paper focused on self-healing efficiency, water permeability, chloride penetration, compressive strength, flexural strength and recovery of water tightness, percentage weight loss of both conventional and bacterial concrete. For good environment tomorrow and better sustainability, self-healing conceptin concrete structure contributes promising technology.

Pressureless Immersion of Epoxy Resin-Filled Cracks in Faulted Rock Materials.

Epoxy resin, known for its excellent corrosion resistance, water resistance, and high-temperature resistance, is extensively utilized in construction and water-related projects. Within water conservancy projects, natural factors such as water impact and weathering often result in cracks within rock formations. Consequently, the application of epoxy resin materials for repair and reinforcement has emerged as a common solution. This research investigates the impact of five epoxy grouting materials, YDS (100:6.4), RH-1 (6.1:1), PSI (9:1), TK (100:8), and HK-G (5:1), on the repair and reinforcement of faulted rock at the Yebatan Hydropower Station. Penetration experiments were conducted on rock samples, and the strength of the epoxy grout samples was tested under ambient conditions of 20 °C, 15 °C, and 0 °C. The experimental results indicate that all five epoxy grout materials successfully penetrated the faulted rock samples. Among them, the PSI (9:1) epoxy grouting material exhibited the most exceptional reinforcing effect across different temperatures, with grouting samples demonstrating strengths in the range of 20 to 25 MPa. This paper confirms that epoxy resin effectively repairs and reinforces rock structures, thereby enhancing the safety and durability of water conservancy projects.

Investigation of epoxy grouts incorporating date palm waste: Mechanical performance analysis

Epoxy grouts, consisting of epoxy resins, hardeners, and fillers, are extensively used in under-grouting due to their excellent mechanical attributes. Waste material incorporation into grout composites is becoming more popular because of growing environmental consciousness and a greater focus on sustainability. Recent research focuses on integrating date palm waste into epoxy grout composites for compression-based applications, such as under-grouting. Additionally, there is a notable gap in the literature regarding the scaling-up process from laboratory experimentation to industrial-scale manufacturing of such grout composites. The present study aims to investigate the feasibility of using date palm midrib wastes for under-grouting heavy machinery and equipment in local industries within Saudi Arabia. Three kinds of epoxy grouts of the exact composition of resin and hardener but with different substitutions of silica sand with date palm midrib waste were made. The microstructure and mechanical properties of the synthesized epoxy grout composites containing varying percentages (2%, 5%, and 10%) of date palm waste, specifically comprising midribs and midrib fibres, are critically assessed. The results show that using midrib fibers resulted in lower mechanical performance of the grout composite than when date palm midribs were used. Moreover, as the amount of date palm waste increases, the mechanical performance of grout specimens decreases. At a 28-day curing time, adding up to 10% date palm waste led to a loss in compressive strength of up to 5% and 66% for the composite containing midribs and midrib fibers, respectively. Correspondingly, adding up to 10% date palm waste reduced flexural strength by 32% and 68% for composite containing midribs and midrib fibers, respectively. Scanning electron microscopy shows that the decline in the mechanical properties of the epoxy composite containing the midrib fibers is attributed to the presence of augmented voids within the microstructure of the specimens. Optical microscopy of epoxy date palm (EDP) specimens shows that the presence of date palm content results in crack propagation along midrib boundaries and through midribs during compressive loading. Except for the grout composite containing 10% midrib fiber, the synthesized epoxy grout composites incorporating date palm midrib waste are more durable and sustainable than the benchmark grout material specified for foundation and heavy machinery applications. The absence of chemical treatments and specialized facilities simplifies the scalability of grout specimen preparation from laboratory to industrial scale.

Exploring Olive Pit Powder as a Filler for Enhanced Thermal Insulation in Epoxy Mortars to Increase Sustainability in Building Construction

This article explores the use of olive pit powder (OPP) as a promising resource for enhancing the thermal insulation properties of epoxy mortars. A comprehensive analysis of the chemical and physical characteristics of OPP was conducted, employing analytical techniques including scanning electron microscopy (SEM), thermogravimetric analysis and emitted gas analysis (TG-MS-EGA), and proximal analysis. Experimental samples of epoxy grout were prepared by using different proportions of a conventional inorganic filler, quartz powder, and OPP within an epoxy mortar matrix. As the percentage of OPP in the formulation increased, the microstructure of the samples gradually became more porous and less compact. Consequently, there was a decrease in density with the increase in OPP content. The 28-day compressive strength decreased from 46 MPa to 12.8 MPa, respectively, in the samples containing only quartz (Sample E) and only OPP (Sample A) as a filler. Similarly, flexural strength decreased from 35.2 to 5.3 MPa. The thermal conductivity decreased from 0.3 W/mK in Sample E to 0.11 in Sample A. Therefore, increasing the %wt of OPP improved insulating properties while reducing the mechanical resistance values. This study highlights the potential of OPP as an environmentally friendly and thermally efficient filler for epoxy mortars, thereby promoting sustainable construction practices.

Experimental assessment of dynamic loading response of grouted non-persistent jointed rock

Grouting is a well-established engineering practice for stabilizing the jointed and/or fractured rock mass. This process may lead to the enhancement of the mechanical properties of fractured rocks. In the majority of the studies, the efficiency of grouting is determined under static loading conditions. Nonetheless, the grouted rock may be subjected to different dynamic loading from blasts or earthquakes. The present study explored the dynamic loading response, in terms of strength and fracture propagation, of a rock mass having a diagonal non-persistent joint (45° to the loading direction) subjected to impact loading to determine the efficiency of grout material. The focus of the study is to present a comparative assessment of different grout materials under dynamic loading. Split Hopkinson Pressure Bar (SHPB) was used to conduct the compressive impact tests on the synthetic rock mass with varying infill conditions (unfilled, cement-filled and epoxy-filled). The progressive fractures within the specimens were monitored by Photron fastcam analysis (PFA, a high-speed image analysis) and digital image correlation (DIC). The experiments highlighted that the strength of rock mass has an increasing trend with the dynamic strain rate. Epoxy resin provided a better strength enhancement than cement paste as the grout material. Due to the higher strength of epoxy resin than cement paste, the epoxy-grouted jointed rock demonstrates a similar response as the intact rock. In the case of both unfilled and cement-filled specimens, the nature of the primary crack was the coplanar shear crack. In contrast, with the injection of epoxy grout, the nature of the initial crack became the tensile or far-field tensile crack, which is often noticed in intact rocks.

Study of Mechanical and Thermal Properties for Epoxy Grouts Subjected to Seawater Conditioning at Elevated Temperature: Tensile Test and Compressive Test

Pipelines and risers are major transportation of oil and gas. These components are often exposed to extreme marine environmental conditions that can cause pipelines to fail due to corrosion. Hence, epoxy grouts are used as a coating material on the surface of pipelines and risers for supporting the pipe structure and corrosion prevention. In this case, the efficiency of epoxy grout is important in pipeline rehabilitation. Research on the adaptation of seawater, temperature, and epoxy grouts is carried out to determine the changes in mechanical and thermal properties of the material. The preparation of epoxy grouts was prepared with a mixture of epoxy resins, epoxy hardeners, and aggregates. After the sample compounds have been flattened, the mixture will be put into the mold. The seawater aging process was performed for seven days before conducting laboratory experiments. After the seawater aging process, there were physical changes on the surface of the epoxy grouts which are the epoxy grout become harder and there were voids that can act as stress concentration points that may cause micro-crack on the specimen. Next, tensile (ASTM 638) experiments were performed at different temperatures of 27°C, 40°C, 52°C, 72°C, 80°C and 100°C while the result of compression experiment is based on the literature critique of past journals. Based on the result, the young modulus and ultimate tensile strength of the epoxy grouts are decreased with increasing temperature. The increment of temperature causes the epoxy grouts to become weaker due to the changes in the polymer matrix structure of the epoxy grouts which lead to the failure at low load and shortens the life of the material. In addition, epoxy grouts are amorphous materials where the glass transition temperature determine the mechanical and physical properties of epoxy grouts. Therefore, the results of the study found that the epoxy grouts changed its mechanical properties from brittle to ductile when the temperature is at 72°C. From the comparison between samples immersed and not immersed in seawater, there is a decrease in Young’s modulus, ultimate tensile stress and strain due to the effect of seawater reaction. In conclusion, the increment in temperature and seawater adaptation factors affect the strength and durability of epoxy grouts.

Monitoring of Substructure Building of Suramadu Bridge Causeway Segment on Surabaya Side Based on Corrosion Level

The structure of the steel pile foundation for the Suramadu Bridge crossroad is located in a corrosive marine area. Air humidity, rainwater, mud, or friction with other objects that cause the protective layer to peel off. Corrosion monitoring is carried out to determine the corrosion rate as one of the steps to prevent corrosion. This study aims to evaluate and monitor the bridge's structure Suramadu Causeway. The evaluation carried out includes observing the damage caused by corrosion. So that it will be known the cause of corrosion and the handling of corrosion protection in the building under the bridge, this study used primary and secondary data collection methods and visual observation of damage from routine inspections carried out. The observations show that the condition of the piles is filled with marine life in the tidal area, while for areas that have never been submerged the condition is quite good. The value of the condition of the structural elements at level 3 - 5, which requires protection on steel pillars that have suffered a lot of damage—handling that needs to be done in the Atmospheric zone and Splash zone / Tidal zone is recommended Recoating, Wrapping, HDPE Jacketing, Epoxy Grouting. In the Submerged zone and the Embedded zone, it is recommended that the Cathodic Protection be replaced (120 kg for 600 mm). So from the results of the research that has been done, it can be used as a study for the maintenance of the Suramadu bridge in preventing corrosion.

RESEARCH ON MECHANICAL PROPERTIES AND GROUTABILITIES OF GROUTED MORTISE-TENON JOINTS FOR PREFABRICATED STRUCTURES

Introduction: The paper addresses grouted tenon-and-groove joints in the prefabricated structure of Changchun subway station. For the first time, grouting of prefabricated structure joints with organic epoxy grouting material is analyzed. Purpose of the study: We aimed to make sure that an organic epoxy grouting material can be injected into the joints uniformly and in full and conducted its experimental study. To establish the applicability of the epoxy grouting material in the prefabricated structures, we studied the mechanical properties of the epoxy grout and its adhesive properties in relation to concrete. Methods: In the course of the study, we used a set of test equipment and an independently developed method. Results: High-quality grouting can be guaranteed at an injection pressure of 0.4 MPa and a temperature of 5–10°C. The relationship between the slurry flow rate and time was fit according to the experimental data at 5 and 10°C. The optimal quartz powder ratio was determined at the level of 1:0.6–1:0.8, and the optimal quartz powder particle size (D50) was determined at the level of 18–25 μm. The results of the study can provide references for similar projects in the future.

Investigating the Effects of Cement and Polymer Grouting on the Shear Behavior of Rock Joints.

This study carried out a comparison between cement grouting and chemical grouting, using epoxy and polyurethane, with respect to their effects on the shear behavior of joints. Joint replicas, with three different grades of surface roughness, were molded and grouted by means of cement and epoxy grouts of various mixtures. To investigate their shear behavior, samples were subjected to direct shear tests under constant normal load (CNL) condition. According to the results obtained, grouting improves the overall shear strength of the rock joints. All the grouted samples yielded higher maximum and residual shear strength in comparison with the non-grouted joint. Grouting resulted in an improvement in the cohesion of all the samples. However, a fall in friction angle by 5.26° in the sample with JRC of nine was observed, yet it was reduced by 2.36° and 3.26° for joints with JRC of 14 and 19, respectively. Cement grouts were found to have a more brittle behavior, whereas the chemical grouts were more ductile. Higher amounts of cement used in the grout mixture do not provide as much cohesion and only increase the brittleness of the grout. As a result of being more brittle, cement grout breaks into small pieces and joint planes are in better contact during shearing; consequently, there would be less of a fall in friction angle as opposed to epoxy grout whose ductile characteristic prevents grout chipping; therefore, joint planes are not in contact and a greater fall in the friction angle occurs. There was no noticeable change in the cohesion of the larger grouted joints. However, the friction angle of both natural and grouted joints increased in the larger joint. This can be related to the distribution of random peaks and valleys on the joint surface, which increases with the joint size.

Effect of Multi-Walled Carbon Nanotubes on Infill Material for Pipeline Composite Repair

The properties of the infill material are an important parameter in predicting the performance and behaviour of Fibre Reinforced Polymer (FRP) composite for effective design. This paper identifies the potential of Multi-walled Carbon Nanotubes (MWCNTs) as nanofiller in enhancing the performance of infill material. Two compositions of MWNTs at 0.1% and 0.5% of weight fractional were evaluated toward neat epoxy on tensile and lap shear test. By comparing MWCNTs-based modified epoxy grouts and neat epoxy grout, a significant increase in tensile strength was observed, especially with 0.5% of MWCNTs by almost 53.3%. While the inclusion of MWCNTs showed a comparable increment in shear strength in both 0.1% and 0.5% weight fractional by 13%. The image of morphologies showed that MWCNTs were well incorporated into the matrix, making the cross-section of the fracture rougher by sharing stress. This shows the potential of the MWCNTs in changing the properties of the modified epoxy grout, provided that the MWCNTs are appropriately dispersed throughout the resin matrix.

Flexural behaviour of circular reinforced concrete columns strengthened by glass fibre reinforced polymer wrapping system

The use of prefabricated glass fibre reinforced polymer (GFRP) wrapping systems in retrofitting reinforced concrete (RC) columns has emerged to enhance the overall axial performance. However, the effect of these systems on columns subjected to bending is still limited although the flexural loading on columns in real life is inevitable. This paper presents experimental, numerical, and theoretical investigations on the flexural behaviour of circular RC columns strengthened by a GFRP wrapping system. A total of eight columns were prepared and tested under three point bending to determine the contribution of the GFRP wrapping system to the overall flexural performance. The annulus between the RC columns and the GFRP wraps was filled with epoxy or cementitious grout to ensure transfer and distribution of stresses. The load-midspan deflection responses and failure modes were presented and evaluated. Furthermore, a nonlinear finite element modelling (FEM) was conducted using ABAQUS software to simulate the performance of unwrapped and GFRP-wrapped columns under flexural loading. A theoretical analysis was also developed using the basic beam theory to obtain the flexural capacity of the tested columns and compare it with experimental and FEM results. A parametric analysis was carried out to assess the effect of varying the thickness of GFRP and infill, as well as the loading mode, on the flexural behaviour of RC columns. The results of experimental tests demonstrated that GFRP-wrapped columns with epoxy infills significantly enhanced the flexural load capacity whereas columns with grout infills showed a prominent enhancement in ductility and energy absorption. The results of FEM and theoretical analyses were in good agreement with experimental results. The results of the developed theoretical model were found to have a good correlation with the results of the parametric investigation. Overall, the GFRP wrapping system implemented in this study is an effective repair technique for structural RC columns subjected to flexural loading. The proposed theoretical model can be used by the practising engineers to design a composite repair system for deteriorated reinforced concrete columns.

Preparation and Properties of Silicon-Modified Epoxy Grouting Material for Repairing Microcracks

To improve the performance of epoxy grouting materials and achieve better repair of microcracks in cast-in-place concrete bridge deck pavements, polydimethylsiloxane (PDMS) and diluent were used to modify epoxy resin. The mechanical properties of silicon-modified epoxy grouting materials produced using different preparation processes were analyzed, and the best preparation process was optimized. The working performance of silicon-modified epoxy grouting material was determined, and the environmental adaptability before and after composite modification was explored. The results showed that the suitable reaction temperature, time, and PDMS content are 100°C, 3 min, and 8%, respectively. The higher the temperature, the better was the groutability and the shorter was the curing time. Therefore, the construction temperature should be at least 35°C. The impact resistance and strength of the grouting materials were improved significantly after the addition of PDMS. In addition, the strength essentially was formed after 5 days. This indicates that the curing age is 5 days. Silicon-based modified epoxy grouting materials have good environmental adaptability. After thermal shock, 30-day temperature variation treatment, and 30 freeze–thaw cycles, the flexibility and bonding properties of the materials were excellent, and were much higher than those of the unmodified materials. Although the tensile strength was slightly lower than that of the unmodified materials, it still remained at about 60 MPa.

Crack-Bridging Property Evaluation of Synthetic Polymerized Rubber Gel (SPRG) through Yield Stress Parameter Identification.

Yield stress parameter derivation was conducted by stress-strain curve analysis on four types of grout injection leakage repair materials (GILRM); acrylic, epoxy, urethane and SPRG grouts. Comparative stress-strain curve analysis results showed that while the yield stress point was clearly distinguishable, the strain ratio of SPRG reached up to 664% (13 mm) before material cohesive failure. A secondary experimental result comprised of three different common component ratios of SPRG was conducted to derive and propose an averaged yield stress curve graph, and the results of the yield stress point (180% strain ratio) were set as the basis for repeated stress-strain curve analysis of SPRGs of up to 15 mm displacement conditions. Results showed that SPRG yield stress point remained constant despite repeated cohesive failure, and the modulus of toughness was calculated to be on average 53.1, 180.7, and 271.4 N/mm2, respectively, for the SPRG types. The experimental results of this study demonstrated that it is possible to determine the property limits of conventional GILRM (acrylic, epoxy and urethane grout injection materials) based on yield stress. The study concludes with a proposal on potential application of GILRM toughness by finite element analysis method whereby strain of the material can be derived by hydrostatic pressure. Comparative analysis showed that the toughness of SPRG materials tested in this study are all able to withstand hydrostatic pressure range common to underground structures (0.2 N/mm2). It is expected that the evaluation method and model proposed in this study will be beneficial in assessing other GILRM materials based on their toughness values.

Experimental research on variable-amplitude fatigue behavior of cracked mortar after epoxy grouting

This paper presents the experimental results of the fatigue behavior of cracked mortar specimens after epoxy grouting reinforcement under high-frequency variable-amplitude fatigue loading. Grouting can effectively suppress the stress concentration at the crack tip and enhance the fatigue resistance of the sample. The final failure mode of the specimen depends on the loading sequence order. We consider the equivalent coefficient and loading sequence, and the multi-step stress level can be equal to a constant value. A log-linear relationship can be obtained between the equivalent stress level and the total fatigue life for both grouted and cracked specimens. In the process of multi-stage fatigue loading, using strain as the damage parameter, it is found that the damage in each loading stage accumulates non-linearly, and the prediction using Palmgren-Miner's rule may be conservative. We propose a nonlinear damage accumulation prediction model that fully considers the loading sequence, equivalent stress level, stress ratio, and other parameters. The test results show that the model can better meet damage accumulation rules and make better prediction effects for multi-stage variable-amplitude fatigue loading.

Experimental and numerical analysis on the effectiveness of GFRP wrapping system on timber pile rehabilitation

Rehabilitation using Glass Fibre Reinforced Polymer (GFRP) wrapping system is an innovative technique for rehabilitation of deteriorated timber structures exposed to severe environmental conditions. This paper investigates the effectiveness of rehabilitation using GFRP wrapping system for deteriorated timber piles due to splitting. An experimental investigation was conducted on undamaged and damaged short timber columns with three levels of splitting. Crane rail epoxy and underwater cementitious grout were used to fill the annulus between columns and GFRP jackets in the rehabilitated samples. All the samples were tested under axial compression loading. Axial peak and yield loads, ductility and energy absorption were discussed to assess the overall behaviour of timber columns. In addition, a finite element analysis was established to investigate the overall load-deformation performance of the tested samples and to validate the experimental results. Furthermore, an analytical prediction was performed based on Australian Standards along with an existing GFRP wrapped stress- strain model to determine the peak load capacity of the unwrapped and GFRP wrapped samples. The experimental results indicated that the GFRP wrapping system can restore the axial capacity and energy absorption of the damaged samples with high effectiveness was observed for samples infilled by the crane rail epoxy. Also, the results of numerical and analytical analysis showed a reasonable correlation with the experimental results.

Preparation and engineering properties of low-viscosity epoxy grouting materials modified with silicone for microcrack repair

Microcracks are common in the cast-in-situ concrete pavement of the bridge deck, DDMS was selected as modifier, AD- I, AD- II and AD- III active diluents were used as viscosity reducers to effectively repair the cracks. And the preparation process of low-viscosity epoxy grouting materials modified by silicone was optimized. Then the working properties (viscosity, gelation time and groutability) and mechanical properties of silicone modified low-viscosity epoxy grouting materials were clarified. Finally, the evolution law of mechanical properties of low-viscosity epoxy grouting material modified by silicone under high temperature impact, temperature change cycle and freeze–thaw cycle was revealed. The results show that the physical and mechanical properties of grouting material prepared under the conditions of reaction temperature 100 °C, reaction time 3 h and DDMS content 11% were the best. The repair depth of low-viscosity epoxy grouting material modified with silicone in 0.5 mm wide crack exceeded 10 cm within 5 min at 25 °C. But its gel time was longer, up to 24 ~ 28 h. After curing for 3 days, the shear strength and bond strength of the silicone modified low-viscosity epoxy grouting material under room temperature reached more than 90%, and its high-temperature shear strength and bond strength reached 70%~90%. Compared with EP grouting material, the low-temperature and normal-temperature impact toughness of the grouting material after adding diluent and DDMS increased by 57%~71% and 31%~48%, respectively. After high-temperature impact, temperature change cycle and freeze–thaw cycle, the mechanical properties of silicone modified low-viscosity epoxy grouting material decreased slightly, but it was still stronger than EP grouting material. Its tensile strength was still higher than 30 MPa, elongation at break was higher than 5.0%, and bond strength was higher than 3.0 MPa.

Seismic Performance of Existing RC Structural Walls Retrofitted in Flexure by Wall End Plate

A study was conducted for the flexural retrofit of an old apartment house composed of a reinforced concrete (RC) shear wall structure. For the shear wall, a vertical retrofit was performed to both ends of the wall targeting the slender wall to improve the flexural performance. The retrofit materials were steel plate, epoxy, and non-shrink grout, and they were connected to the existing shear wall using post-installed chemical anchors. The concrete at the wall ends was broken and retrofitted as much as necessary to maintain the shear wall’s length. The points to be noted are the fracture of the welded part of the flexural retrofit and the chemical anchor’s pulling. After the real scale specimen was fabricated by simulating the existing shear wall, the retrofit effect was experimentally verified by breaking the wall ends, retrofitting the ends, and applying repeated cyclic lateral loads. A total of three specimens were fabricated and retrofitted using steel plates and steel tubes. Since this experiment evaluated the flexural performance, the experiment was performed with a cantilever setting. The flexural retrofit effect using steel was analyzed through the load–displacement relationship, stiffness degradation, and energy dissipation, and through this, the bond of the retrofit and the behavior of the wall were verified.

Epoxy-based grouting materials with super-low viscosities and improved toughness

The main goal of this work was to prepare epoxy grouts with super-low viscosities that could be easily inserted into the micro-cracks of construction materials. The combinations of two diluents—acetone with 1,6 hexanediol diglycidylether (RDDF) or trimethylolpropane glycidylether (RDTF)—were developed for epoxy grouting materials. To clarify the effects of the combined diluents on the epoxy grouting materials, experiments to determine the viscosity and mechanical characteristics and SEM were carried out. The combined diluents could not only dramatically reduce the viscosity of the epoxy solution but could also modify the brittleness of the neat epoxy. To further describe the mechanism, Fourier-transform infrared spectroscopy, thermogravimetric analysis, and dynamic mechanical analyses were used to investigate the molecular modification of the epoxy network. The modification of the epoxy groups contributed to the properties of the epoxy grouts, accelerated the reaction with the curing agents and the ether groups, and improved the flexibilities of the epoxy grouts. Furthermore, the tests of the acute oral toxicity showed that the median lethal oral dose exceeded 5000 mg/kg and could be considered non-toxic. Epoxy grouting materials with super-low viscosities can be used for repairing micro-fractures in construction.

Shear testing of URM wallettes retrofitted with NSM steel wire rope

An experimental program was undertaken with the aim of investigating the in-plane behaviour of unreinforced clay-brick masonry (URM) wallettes retrofitted using the near surface mounted steel wire rope (NSM-SWR) method. A total of ten double-leaf URM wallettes, each with dimensions of 1200 mm × 1200 mm × 235 mm, were tested in induced diagonal shear. One wallette was tested in the as-built condition and was used as a benchmark to define the performance of the nine wallettes that were retrofitted with different configurations of lengths of NSM-SWR. Two-part epoxy and cement grout were used as adhesives to provide coupling between the wire rope and the clay-brick masonry. Several parameters affecting the shear behaviour of the retrofitted URM wallettes were investigated, including the failure mode, shear strength, maximum drift and pseudo-ductility, with the results and associated analysis presented herein.

Effect of Silica Sand Filler on Mechanical Properties of Epoxy Grout for Composite Repair of Steel Pipelines

Abstract Oil and gas pipes are vulnerable to failure initiated by corrosion because of their operating pressure under adverse conditions. A composite repair assembled around the pipe with a small gap that is then infilled with epoxy grout is considered a suitable option for repairing corroded pipelines. This article presents an investigation into the mechanical properties (compressive, tensile, and flexural) of epoxy grout, with and without inclusion of silica sand as a filler. The mechanical tests were carried out in accordance with American Society for Testing and Materials standards. Experimental results on mechanical properties indicate that the strength in tensile and flexural mode for the grout decreases with the inclusion of filler because of a weak interface between the matrix and filler. However, the addition of filler in grout showed an increase in compressive, tensile, and flexural modulus. Based on suggested properties in a previous study, both grouts have the potential to be used on structural rehabilitation, especially for repairing damaged pipeline.