Mesh Reinforcement Research Articles

Retromuscular, periprosthetic drainage after hernioplasty with sublay mesh reinforcement in ventral hernias results in less retromuscular fluid collections but longer hospital stay and analgetic use with unclear effect on clinical outcome - a randomized controlled trial

PurposeTo determine whether periprosthetic drain insertion for hernioplasty using sublay mesh augmentation influences retromuscular fluid collections (RFC) and the clinical course.MethodsForty-two patients with open repair of midline hernias (M2-4, W1, European Hernia Society classification) were allocated to groups with or without retromuscular drains. Subcutaneous drainages were used in both groups to avoid confounding from surgical site occurrences due to superficial, subcutaneous fluid collections. The participants underwent clinical and ultrasound assessments on postoperative days (POD) 14 and 30 to detect RFC, subcutaneous seromas, and wound complications. The sample size was estimated using the RFC of a test cohort with drainage; the assumed relevant volume (5 ml) was calculated comprising 84% (mean + 1 SD) of these patients.ResultsIn the retromuscular drainage group, the RFC median volume was reduced by 75.2% on POD 14, and by POD 30, no RFC were found [0.2 vs. 25.8 (p < 0.001) and 0 vs. 4.0 (p = 0.02) on PODs 14 and 30, respectively]. The number of patients with RFC ≥ 5 mL was also significantly lower in the drainage group [4 vs. 12 (p = 0.02) and 1 vs. 8 (p = 0.02) on PODs 14 and 30, respectively]. No surgical site infections occurred in either group, but retromuscular hematoseroma led to one revision surgery and one needle aspiration in the group without drainage. In the drainage group, a significantly longer hospital stay (6.5 days vs. 4 days; p = 0.01) and longer regular analgetic intake (6 vs. 3 days; p = 0.03) were observed. Multivariable regression revealed that retromuscular drainage usage was the only independent predictor of the RFC volume.ConclusionWe found that the use of retromuscular drains after hernioplasty with sublay hernia repair reduced periprosthetic fluid collections in our population but prolonged hospital stay. Whether the reduction of RFC can prevent SSO or revision surgery cannot be determined from our data, the relevance is therefore not assessable. Hence, further larger studies are required to determine the clinical relevance of drains.

Chemical Bath Deposition of NiFe Alloy Anode for Efficient Alkaline Water Electrolyzer Integration.

Green hydrogen production from water splitting is a feasible way for intermittent renewable energy storage and utilization, where the exploration and scale-up preparation of high-performance anodic oxygen evolution electrocatalysts are critical prerequisites for its industrial-level applications. Herein, a chemical bath deposition of FeNi3 intermetallic alloys onto Ni mesh support is performed, which delivers a current density of 0.62 Acm-2 at 1.72 V versus reversible hydrogen electrode for alkaline water oxidation in 1 m KOH and an excellent electrolysis stability at 0.2 A cm-2 for over 300 h. Moreover, via 3D computational fluid dynamics simulation and flow field optimization, a homogeneous deposition of ≈5400 cm2 NiFe anode is demonstrated within 4 min using the developed flow bath reactor. Once integrating the as-prepared NiFe anodes into alkaline electrolyzer stack, the voltage variation between each unit cell is below 40 mV at a total operation current of 71 A, or ca. current density of 0.2 A cm-2, confirming the uniformity of this batch synthesis protocol and its great potential for industrial alkaline water electrolysis.

OpenSBLI v3.0: High-fidelity multi-block transonic aerofoil CFD simulations using domain specific languages on GPUs

OpenSBLI is an automatic code-generation framework for compressible Computational Fluid Dynamics (CFD) simulations on heterogeneous computing architectures (previous release: Lusher et al. (2021) [4]). OpenSBLI is coupled to the Oxford Parallel Structured (OPS) Domain Specific Language (DSL), which uses source-to-source translation to enable parallel execution of the code on large-scale supercomputers, including multi-GPU clusters. To date, OpenSBLI has largely been applied to compressible turbulence and shock-wave/boundary-layer interactions on very simple geometries comprised of single mesh blocks with essentially orthogonal grid lines. OpenSBLI has been extended in this new release to target strongly curvilinear cases, including transonic aerofoils using multi-block grids. In addition to multi-block mesh support, more efficient numerical shock-capturing methods and filters have been added to the codebase. Improvements to post-processing, reduced-dimension data output, and coupling to a modal decomposition library are also included. A set of validation cases are presented to showcase the new code features. Furthermore, state-of-the-art wide-span transonic aerofoil simulations on up to N=2.5×109 grid points demonstrate that wider aspect ratios can alter buffet predictions and increase the regularity of the low-frequency shock oscillations by accommodating fully-developed trailing edge flow separation. Spectral Proper Orthogonal Decomposition (SPOD) analysis showed that overly-narrow aerofoil simulations contain additional domain-dependent energy content at a Strouhal number of St≈3 associated with wake modes.

Effects of Stainless Steel Woven Wire Mesh Reinforcement on the Load-Bearing Capacity of Adhesively Bonded Aluminium Alloy Single-Lap Joints

Effects of Stainless Steel Woven Wire Mesh Reinforcement on the Load-Bearing Capacity of Adhesively Bonded Aluminium Alloy Single-Lap Joints

PROsthetic MEsh Reinforcement in elective minimally invasive paraesophageal hernia repair (PROMER): an international survey.

The optimal treatment for paraesophageal hiatus hernia (PEH) is controversial. While crural buttressing with mesh shows promises in reducing recurrences, the decision to use mesh during minimally invasive PEH repair is largely subjective. Due to these uncertainties, we conducted a survey to examine current clinical practices among surgeons and to assess which are the most important determinants in the decision-making process for mesh placement. Thirty-five multiple-choice Google Form-based survey on work-up, surgical techniques, and issues are considered in the decision-making process for mesh augmentation during minimally invasive PEH repair. Responses were graded on a 5-point Likert scale and analyzed using descriptive statistics. Consensus was defined as > 70% of participants agreed (agree or strongly agree) on a specific statement. Overall, 292 surgeons (86% from Europe) participated in the survey. The median age of participants was 42years (range 29-69). The median number of PEH procedures was 25/year/center (range 5-400), with 67% of participants coming from high-volume centers (> 20 procedures/year). Consensus on use of mesh was reached for intraoperative findings of large (> 50% of intrathoracic stomach) PEH (74.3%), crural gap with > 4cm distance between right and left crus (77.1%), and/or crural atrophy with < 0.5cm thickness of one or both pillars (73%), and for redo surgery (71.9%). Further, consensus was reached in defining recurrence as a combination of refractory symptoms and anatomical/radiological evidence of > 2cm hernia. This survey shows that large PEH, wide crural transverse diameter, fragile crura, and redo surgery are the most influential issues driving the decision for mesh-reinforced cruroplasty.

Utility of falciform ligament flap for hiatal hernia repair: a systematic review.

Surgical repair of hiatal hernia (HH) is plagued by high recurrence rates. Hiatoplasty failure has been identified as a major determinant of recurrent symptoms and HH, but there is no consensus on the optimal surgical approach to minimize this complication and hiatal mesh reinforcement remains controversial. The use of the falciform ligament as an autologous rotational flap to support crural repair has been proposed as a potential solution. This review aims to evaluate the safety and efficacy of the falciform ligament flap (FLF) as an adjunct in HH repair. Searches were conducted on Google, Google Scholar, PubMed, Scopus, Web of Science, and Cochrane through May 2024. The primary study outcome was HH recurrence rate. Secondary outcomes included 30-day mortality rate, postoperative morbidity, and length of hospital stay. Descriptive statistics were used to analyze the data. Twelve studies comprising 469 patients undergoing FLF augmentation during primary or revisional HH repair were included. The majority (80.7%) of patients had HH types III-IV. Crural suture hiatoplasty was performed in all cases, and adjunctive mesh reinforcement was reported in two studies. Postoperative morbidity was 4.6%, and there was no mortality. The overall HH recurrence rate was 5.8% (range 0-15.4%). Our study seems to suggest that FLF may reduce postoperative HH recurrence. Well designed and comparative studies with long-term follow-up are required to confirm these preliminary data.

Tracheobronchoplasty for severe tracheobronchomalacia: a case-series of patients with acute and chronic critical comorbidities.

There is little data within the literature regarding tracheobronchoplasty (TBP) in the setting of the acute and chronically ill, morbidly obese, or ventilator dependent patients with Tracheobronchomalacia (TBM). Short- and long-term outcomes are studied. The series represents 12 TBM patients with American Society of Anesthesiologists (ASA) physical status scores of 3 to 5. Candidacy was based on bronchoscopic findings during spontaneous respirations with >90% collapse of the trachea and both mainstem bronchi. We used dynamic CT scan as an adjunct in those not mechanically ventilated. Our operative approach was a complete portal robotic approach for those outpatients (wheelchair dependent) and right thoracotomy for those who were already mechanically ventilated with 100% fraction of inspired oxygen (FiO2) with high pressure. Extracorporeal support was used in 2 patients. Patients who underwent robotic repair, were discharged without complications. Two patients who were critically ill and required extracorporeal support for their surgeries, were separated from extracorporeal membrane oxygenation (ECMO) on postoperative day 2. Three patients died at the follow-up. In 1 patient, the prolene mesh migrated into trachea and caused obstruction of the trachea and required removal with endobronchial techniques. The repair of TBM in patients with multiple comorbidities and with severe life-threatening problems in or outside the ICU, may have improvement due to the ability to wean from positive pressure ventilation. Surgical technique and the utilization of mesh support in TBP operations may need to be debated due to duration of the surgery in patients with severe comorbidities.

Comparative anatomic and symptomatic recurrence outcomes of diaphragmatic suture cruroplasty versus biosynthetic mesh reinforcement in robotic hiatal and paraesophageal hernia repair.

Hiatal and paraesophageal hernia (HH/PEH) recurrence is the most common cause of failure after gastroesophageal anti-reflux surgery. Crural reinforcement with mesh has been suggested to address this issue, but its efficacy remains debated. In this study, we aimed to determine the impact of biosynthetic mesh reinforcement compared to suture cruroplasty on anatomic and symptomatic hernia recurrence. Data of patients who underwent robotic HH/PEH repair with suture cruroplasty with or without biosynthetic mesh reinforcement between January 2012 and April 2024 were retrospectively reviewed. Gastroesophageal reflux disease symptoms and anatomic hernia recurrence were assessed at short-term (3months to 1year) and longer-term (≥ 1year) follow-up. Symptomatic hernia recurrence was defined as having both anatomic recurrence and symptoms. Out of the 503 patients in the study, 308 had undergone biosynthetic mesh repair, while 195 had suture-only repair. After the surgery, both groups demonstrated comparable improvements in symptoms. Short-term anatomic hernia recurrence rates were 11.8% and 15.6% for mesh and suture groups, respectively (p = 0.609), while longer-term rates were 24.7% and 44.9% (p = 0.015). The rates of symptomatic hernia recurrence in the same group were 8.8% and 14.6% in the short-term (p = 0.256), and 17.2% and 42.2% in longer-term follow-ups (p = 0.003). In the repair of medium and large-size hernias, mesh reinforcement resulted in a 50.0% relative risk reduction in anatomic hernia recurrences and a 59.2% reduction in symptomatic hernia recurrences at ≥ 1-year follow-up. After more than a year of follow-up, it has been found that using biosynthetic mesh for medium and large hiatal or paraesophageal hernia repair significantly reduces the likelihood of both anatomic and symptomatic recurrence compared to using only suture cruroplasty. These findings strongly support the use of biosynthetic mesh to manage larger hernias. However, further long-term multicenter randomized studies are needed to provide more conclusive evidence.

420. MESH REINFORCEMENT IN HIATAL HERNIA REPAIR: CLINICAL RESULTS OF OUR EARLY EXPERIENCE

Abstract Background Approximately one-third of the population develops diaphragmatic hernias among which only 10% are symptomatic. Restoration of the normal anatomy, hiatus closure and fundoplication are effective methods in the surgical treatment of diaphragmatic hernia repair. Placement of absorbable meshes to cover the hiatal closure emerges as a new, albeit controversial in the literature, technique for reinforcement. This study aims to assess the quality of life of patients diagnosed with hiatal hernia who underwent Nissen or Toupet fundoplication with absorbable biosynthetic mesh placement covering the suturing of the hiatus as an additional step during the laparoscopic or robotic hiatal hernia repair. Methods Data of all patients who underwent Nissen or Toupet fundoplication with absorbable mesh reinforcement at the hiatus between 2020-2023 at our specialised unit was collected and analysed. Thirteen patients who had completed their 6-month and 1-year postoperative follow-up, were interviewed. GERD score, PPI use and postoperative endoscopy were evaluated. Results Occasional use of PPI was reported by one patient, whereas those who had already undergone endoscopy of the upper gastrointestinal tract presented no signs of esophagitis, recurrence of hernia or Barrett esophagus. One patient reported symptom improvement after the operation with a GERD score of 13, while the rest of the patients had a GERD score of 0 (12/13). Conclusion The treatment of diaphragmatic hernias with Nissen or Toupet fundoplication using absorbable mesh reinforcement of the hiatus after closure with sutures seems to be an effective therapeutic method with a success rate over 90% in our case series provided that the rest of the surgical steps are identical between the cases through a well-established technique by our surgical team. However, further studies with larger number of patients and longer follow-up are mandatory aiming to further investigate the potential benefits when mesh reinforcement is applied.

806. MINIMALLY INVASIVE REVISION FUNDOPLICATION, IS IT SAFE AND FEASIBLE? SINGLE CENTER EXPERIENCE

Abstract Introduction Laparoscopic fundoplication has become standard of care for patients with refractory gastroesophageal reflux disease, large and symptomatic hiatal hernia. Failure rate for laparoscopic fundoplication was between 2 to 17%. Doing Revisional Antireflux surgery is technically difficult. Our aim is to analyse symptomatic improvement post surgery, safety and durability of procedure in patients who underwent revision fundoplication at our centre Patients and Methods 22 patients underwent Minimally invasive revision fundoplication between January 2019 to January 2022 were taken into study, of them 12 gentlemen and 10 women were noted. Modified DeMeester score was calculated in all patients preoperatively and on 6 months follow up. Results All patients underwent primary surgery laparoscopically. 14 patients (63.6%)had recurrent reflux symptoms and 8 patients (36.3%) had severe dysphagia. Revision fundoplication was done laparoscopically in 20 patients and 2 patients Robotic surgery was done. Intraoperatively 11 patients had wrap migration, 8 patients had tight wrap, 3 patients had twist of wrap. In the re-do anti-reflux surgery (ARS) procedure, floppy Nissen fundoplication was performed in 86.4% of the patients, which amounts to 19 patients., and 3 patient underwent a 270-degree Toupet fundoplication. In 2 patients, additional composite mesh reinforcement was employed. 13.6 % of patients had intraoperative complications, 9.09 % of patients had pleural injury, 4.7 % had intraoperative bleeding, 9.09% of patients had gallstone disease, for which cholecystectomy was done. All patients anterior and posterior vagus identified and preserved. On follow up 80% of patients had resolution of symptoms, 18% needed intermittent PPI. At a median follow up of 18 months, no surgical failure was noted in endoscopy. Conclusion Laparoscopic revision fundoplication is a safe procedure when operated in a high volume centre by an expert surgeon.

Modified Chevrel Technique: A Lifesaver for Surgeons.

Background and Objectives: Ventral hernias (VH) pose significant challenges for surgeons due to the risk of recurrence, complexities in aligning abdominal muscles, and selecting the most suitable layer for mesh augmentation. This study aims to evaluate the effectiveness of utilizing the anterior rectus fascia as a turnover flap in conjunction with onlay mesh reinforcement, a procedure known as the modified Chevrel technique (MCT). Materials and Methods: We conducted a retrospective analysis of patients who were operated on using MCT for abdominal hernias between January 2013 and December 2019. Data were extracted from our hospital's electronic database. Recurrence rates, as well as the rates of surgical site occurrences (SSO), surgical site infections (SSI), and surgical site occurrences requiring procedural intervention (SSOPI), were analyzed based on patients' comorbidities and demographic characteristics. Results: The median follow-up period was 42.9 months (range: 14-96), and the recurrence rate was 4% (n = 3). Among the recurrent cases, three patients had chronic obstructive pulmonary disease, representing a statistically significant association (p = 0.02). Although all patients with recurrence were obese, this association did not reach statistical significance (p > 0.05). The mean hospitalization duration was 17.6 days (range: 6-29). SSO, SSI, and SSOPI rates were 39 (52%), 12 (16%), and 32 (42%), respectively. Conclusions: Managing VH remains a surgical challenge, emphasizing the importance of achieving effective abdominal closure for both functional and cosmetic outcomes. MCT presents a relatively simple approach compared to techniques like transversus abdominis release (TAR) and anterior component separation (ACS), with acceptable rates of SSO, SSOPI, SSI, and recurrence.

A New Era in Perforator Flap Surgery for Breast Reconstruction: A Comparative Study of Robotic versus Standard Harvest of Bilateral Deep Inferior Epigastric Artery Perforator Flaps.

Traditional deep inferior epigastric artery perforator (DIEP) flap harvest splits the anterior sheath, weakening the abdominal wall and predisposing patients to bulge or hernia. Abdominal wall morbidity may be decreased using minimally invasive techniques. We refined a transabdominal approach to the robotic harvest of bilateral DIEP flaps. A retrospective medical record study involving all patients who underwent bilateral or bipedicled robotic DIEP (rDIEP) or standard DIEP (sDIEP) flap harvest between July 2021 and September 2022. Outcomes included abdominal wall morbidity, total operative time, length of stay (LOS), and complications. Forty-seven patients were included (48 sDIEP flaps, 46 rDIEP flaps) with no significant difference in patient characteristics. Fascial incision length in the rDIEP group was shorter (4.1 vs. 11.7 cm, p < 0.001). Mesh reinforcement of the abdominal wall was used in 13/24 sDIEP and none in rDIEP patients (p < 0.001). Operative time was longer in the rDIEP cohort (739 vs. 630 minutes, p = 0.013), although subanalysis showed no difference in the second half of the cohort. The average robotic dissection time was 135 minutes, which decreased significantly with the surgeon's experience. There were no intraoperative complications from using the robot. LOS was shorter with rDIEP but not statistically significant (3.9 vs. 4.3 days, p = 0.157). This study represents the most extensive cohort analysis of bilateral rDIEP flap harvest, offering a comprehensive comparison to traditional sDIEP. The initial results underscore the viability of robotic techniques for flap harvesting, highlighting potential advantages including reduced fascial incision length and decreased abdominal disruption. Furthermore, using robotics may obviate the necessity for fascial reinforcement with mesh.

Optimising shapes of multiple pin fins in a microchannel using deep reinforcement learning and mesh deformation techniques

The utilisation of advanced pin fin designs in microchannels is useful for enhancing cooling efficiency. Advancements in machine learning and processing power have sparked interest in shape optimisation techniques. This research employs a novel framework that integrates Deep Artificial Neural Networks and Reinforcement Learning with a Computational Fluid Dynamics (CFD) solver to optimise multiple pin fin shapes within a microchannel. By incorporating Radial Basis Function interpolation and Proximal Policy Optimisation alongside FLUENT, acting as the CFD environment, the reinforcement learning agent adeptly explores the design space to enhance the thermohydraulic performance factor (TPF), aiming to maximise Nusselt number while minimising pressure loss. Unlike previous heat transfer optimisation studies, which typically required mesh regeneration at each step, the proposed framework could bypass the meshing step and alter the geometry directly by relying on the RBF interpolation technique to deform the mesh directly. Three distinct scenarios investigated in this study are uniform deformation of all pin fins, deformation of all pin fins arranged in two rows, and individual deformation of each pin fin. Extensive simulations, exceeding 90,000 different cases, demonstrate that although the optimisation process for the individual deformation of each pin fin requires more iterations compared to others, it surpasses them in terms of TPF improvement. Notably, significant improvements are achieved, such as a 49 % enhancement in Nusselt number and a 33 % reduction in pressure drop, culminating in an impressive 63 % increase in TPF compared to the initial geometry.

Enhancing Clay-Based 3D-Printed Mortars with Polymeric Mesh Reinforcement Techniques.

Additive manufacturing (AM) technologies, including 3D mortar printing (3DMP), 3D concrete printing (3DCP), and Liquid Deposition Modeling (LDM), offer significant advantages in construction. They reduce project time, costs, and resource requirements while enabling free design possibilities and automating construction processes, thereby reducing workplace accidents. However, AM faces challenges in achieving superior mechanical performance compared to traditional methods due to poor interlayer bonding and material anisotropies. This study aims to enhance structural properties in AM constructions by embedding 3D-printed polymeric meshes in clay-based mortars. Clay-based materials are chosen for their environmental benefits. The study uses meshes with optimal geometry from the literature, printed with three widely used polymeric materials in 3D printing applications (PLA, ABS, and PETG). To reinforce the mechanical properties of the printed specimens, the meshes were strategically placed in the interlayer direction during the 3D printing process. The results show that the 3D-printed specimens with meshes have improved flexural strength, validating the successful integration of these reinforcements.

Giant left spontaneous diaphragmatic hernia repair via combined laparoscopic and thoracoscopic approaches.

Spontaneous diaphragmatic hernias (DHs) are uncommon, yet potentially hazardous. To prevent consequences, timely diagnosis and treatment are necessary. A 54-year-old male presented to the emergency room with dyspnoea, cough and tachycardia; he had no history of trauma. Diagnostic imaging revealed a substantial left DH, indicating the need for surgical intervention. The intraoperative examination identified a transverse colon and omentum herniation. Dissection, reduction of the contents, primary sutures of the defect and dual mesh reinforcement accomplished the laparoscopic and thoracoscopic DH repair. This case underscores the importance of timely detection, precise surgical intervention and comprehensive post-operative monitoring when utilising a multidisciplinary approach to manage DHs. It serves as a reminder to exercise caution regarding DHs, particularly in circumstances devoid of traumatic aetiology and the benefits of combined laparoscopic and thoracoscopic approaches.

Posterior components separation with transversus abdominis release and sublay mesh reinforcement in large ventral hernia repair

AbstractAimVentral abdominal hernia is a prevalent condition among surgical patients. Large ventral hernias with defects &gt;10 cm that cannot be closed primarily, often with loss of domain requiring abdominal wall reconstruction, pose a surgical challenge. Our study aimed to evaluate the outcomes of posterior components separation (PCS) with transversus abdominis release (TAR) and sublay mesh reinforcement in large ventral hernia repair, particularly in terms of surgical site occurrences (SSOs) and hernia recurrence.Patients and MethodsOur study included 40 adult patients presented to Tanta University Hospitals with a large ventral hernia (defect width ≥10 cm) from December 2021 to January 2023. All patients were submitted to PCS with TAR and sublay mesh reinforcement.ResultsThe mean age of the study population was 47.32 (standard deviation [SD] 9.31) years (range 36–65 years) with a mean body mass index of 33.55 (SD 3.42) kg/m2 (range 28.35–38.72 kg/m2). The major risk factors were obesity (95.00%), smoking (45.00%), and multiparity (45.00%). Midline incisional hernia was the most common type in 28 patients (70.00%). Thirty‐four patients (85%) achieved successful midline closure, while six patients required additional anterior components separation technique to achieve tensionless midline closure and an onlay mesh for functional reconstruction. Post‐operative SSOs occurred in 12 patients (30.00%), with subcutaneous seroma in 8 patients (20.00%) and wound dehiscence and necrosis in 4 patients (10.00%). Two patients (5.00%) experienced recurrence after a mean follow‐up period of 19.25 (SD 3.52) months.ConclusionsPCS with TAR and sublay mesh reinforcement is a reliable and durable technique for complex ventral hernia repair with low morbidity and recurrence rates. However, long‐term clinical outcomes with more cases are required to properly evaluate this technique.

Influence of manufactured sand, recycled aggregate, reinforcement ratio and wire mesh on the response of reinforced concrete slabs under impact loading

Targeting towards the sustainable goal, the emergence of manufacturing sand (M-sand) and recycled coarse aggregate (RCA) as an alternate for natural aggregates has unfolded new prospects for constructional practices in the world. Therefore, the investigation is focused to study the influence of RCA, M-Sand, Combination of RCA and M-sand, wire mesh and steel reinforcement under impact loading. The reinforced concrete slabs (1 layer @ 25 mm c/c) slabs [S1-S4, S9, S11, S13 and S15] was studied using M-sand (100 %) and recycled coarse aggregate (25 %) with a concrete compressive strength of 40–50 MPa. Also, the flexural reinforcement was varied as 0.23, 0.32 and 0.39 % of the cross-section area. The experimental results were presented in terms of failure pattern, impact force-reaction force, midpoint displacement and energy absorption capacity. It was observed that the spalling of concrete to the conventional slab (S1) whereas, the spalling of concrete as well as formation of radial cracks were observed on slab with RCA (S2). It was also observed that the severe spalling with formation of radial cracks in the slab with M-sand and RCA (S4), however the impactor did not perforate. The peak impact force on control slab, S1, S2, S3 and S4 was 145, 187, 122 and 167 kN, respectively. The significant increase in peak impact force in S2 is due to the use of micro silica fume treatment which enhanced the mechanical properties of RCA. The peak impact force in slab S3 by M-sand found reduced by 15 %, whereas the same was found increased by 15 % in case of slab S4 by RCA and M-sand, as compared to S1. The maximum crack width in slab S15 was limited to 1–2 mm whereas same was found to be 9–10 mm in case of slab S13. The use of wire mesh found to enhance the global bending deformations as well as crack width in the slab. It is concluded that the utilization of wire mesh along with steel reinforcement proves to be an effective method to diminish the permanent deformation. Further, finite element software ABAQUS was used to model the slab under impact loading and the results were compared with the experimental results. The predicted peak impact force of slab S1 was found to be good agreement with the experimental results. However, the predicted peak impact force on slab S2-S4 found to have maximum deviation 11 % as compared to experimental results.

Bending analysis of textile reinforced concrete sandwich panels: Experimental and numerical evaluation

Textile reinforced concrete (TRC) is a combination of a cementitious matrix and a textile reinforcement that has good mechanical properties. This makes a highly promising composite material for a wide range of construction practices. One notable application of this innovative composite deals with the production of thin sandwich panels. Hence it is noteworthy to examine the control parameters (depth & number of layers) that affect the mechanical properties of TRC sandwich panels with chosen fibre meshes and core material.Initially, 24 different TRC panels were cast and modelled with varying depths (45 mm, 55 mm and 65 mm) and layers (3, 4, 5 and 6), incorporating two different fibre mesh reinforcements. The flexural behavior of these panels was studied both experimentally and numerically using ABAQUS software. The optimized control parameters was obtained from the results was TRC panel of 5 layers of Aramid fibre mesh having 55 mm depth.Further exploration focused on the effect of overall depth variation on the flexural behavior of TRC sandwich panels. A panel with Aramid fibre reinforcement and a calcium silicate board core, featuring a 55 mm overall depth, exhibited a remarkable 69.49 % increase in bending stress compared to a panel with a depth of 118 mm. These findings underscore the significance of optimized control parameters, showcasing the potential for enhancing the mechanical performance of TRC sandwich panels in construction practices.

Concentrically loaded concrete columns reinforced with steel-FRP composite bars (SFCB) and carbon fibre-reinforced polymer mesh fabric (CFRP-MF) stirrups

Corrosion of rebar is a major cause of performance degradation in coastal structures, and thereby, significantly affects their durability and safety. To address this issue, a new corrosion-resistant reinforced composite structural concrete column were formed by using basalt fibre-reinforced composite bar (SFCB) as the longitudinal reinforcement and carbon fibre-reinforced polymer mesh (CFRP-MF) as an alternative to stirrup. Eight columns were subjected to an axial compression test to determine their capacity. The effects of different combinations of embedded reinforcement, concrete strength, and CFRP-MF stirrup ratio on the cracking performance, ductility, and axial load carrying capacity were investigated. A nonlinear finite element modelling was used to predict axial compressive response of concrete column reinforced with SFCB and CFRP-MF stirrups, and parametric analyses were conducted. The experimental results indicated that all tested columns reinforced with CFRP-MF stirrups were damaged in the central region of the specimens with extensive peeling of the protective layer. To ensure optimal structural safety, it is recommended that SFCB adopt the equal stiffness alternative method to replace longitudinal reinforcement. The substitution increases load-carrying capacity and ductility of the specimen by 5.4 % and 7.8 %, respectively. The study proposes an improved design model for predicting the Nu of columns reinforced with SFCB and CFRP-MF stirrups, which enhances prediction accuracy and precision when compared with existing codes. The findings contribute innovative insights and practical recommendations for advancing the utilization of seawater sea sand concrete and its application in coastal engineering projects.

PENGARUH SERAT BAMBU TERHADAP KAPASITAS LENTUR PELAT BETON CAMPURAN STYROFOAM DEGAN PERKUATAN TULANGAN WIREMESH

Lightweight concrete is a concrete technology innovation that is currently developing. The advantage of lightweight concrete is that it uses less time and costs compared to concrete in general but has the disadvantage of lower strength. This research aims to determine the effect of adding bamboo fiber on the flexural capacity of lightweight concrete slabs mixed with Styrofoam. The lightweight concrete mixture used is Styrofoam at 50% of the weight of the mixed aggregate. Variations in adding bamboo fiber with a diameter of 1 mm and a length of 40 mm are 0% and 0.5% of the cement weight. The test object consists of a lightweight concrete plate measuring 50 cm x 150 cm x 8 cm with wire mesh reinforcement with a diameter of 8 mm. Tests were carried out when the concrete was 28 days old by applying an even load gradually until the slab collapsed. From the test results, at a loading of 300 kg, the average deflection value for lightweight concrete slabs with reinforcement reinforcement with 0% bamboo fiber was 1.18 mm and for lightweight concrete slabs with 0.5% bamboo fiber was 1.57 mm. Lightweight concrete slabs mixed with bamboo fiber have a greater deflection than lightweight concrete slabs without a mix of bamboo fiber. This shows that the addition of bamboo fiber to lightweight concrete slabs does not increase the flexural capacity of the slab. The difference between theoretical calculations and testing is due to the theoretical calculation formula used in this research not taking into account the content and properties of Styrofoam in the plates. The two variations of concrete slabs used in the test did not experience any cracks and met the maximum allowable deflection requirements at loads reaching 300 kg.