Performance Concrete Research Articles

Enhancing the Performance and Behaviour of M35 Alccofine 1203 Grade Concrete

Abstract: The construction industry faces pressures to reduce its environmental footprint, prompting the exploration of sustainable materials that maintain or enhance conventional concrete's performance. This study investigates Alccofine 1203, a high-performance micro-fine material, as a partial cement replacement in concrete. The objective is to determine optimal Alccofine percentages for desired mechanical properties and sustainability benefits. We conducted experimental trials with concrete mixes where cement was replaced by Alccofine at increments of 5%, 10%, and 15%. Multiple concrete cubes were prepared and tested for compressive strength, flexural strength, workability, and durability. Fresh properties were evaluated using slump and flow tests, ensuring adequate workability, while long-term performance was assessed through durability tests, including permeability and chloride ion penetration. The results indicate that a 10% replacement of cement with Alccofine 1203 enhances the compressive strength and durability of concrete without compromising workability. Higher percentages showed varied results, necessitating further investigation to optimize the mix design. This study highlights the potential of Alccofine 1203 as a sustainable alternative to traditional cement, offering significant implications for eco-friendly construction practices. This research contributes to the field by providing empirical data on Alccofine 1203's effects in concrete, supporting the development of more sustainable building materials. Future work will focus on refining mix proportions and exploring Alccofine's impact on other concrete properties such as shrinkage and creep.

An experimental investigation on mechanical characteristics of steel-fiber-reinforced volcanic concrete

Raw materials of concrete are one of the main pollution resources. Sustainable concrete is one of the significant solutions that can be used to reduce carbon emission. This study aims to use volcanic ash (VA) as a supplementary cementitious material (SCM) for producing sustainable concrete. The effects of VA on the properties of steel fiber reinforced concrete (SFRC) are evaluated. The fresh and hardened concrete's characteristics of steel fiber volcanic ash concrete (SFVC) is presented and assessed. Slump test, compressive strength, splitting tensile tests, scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and Fourier transform infrared (FTIR) spectrophotometry are used to investigate the effect of VA concrete performance. Five groups of SFVC were prepared using sixteen different mixes; 0 %, 2.5 %, 5.0 %, and 7.5 % of VA were used as a partial replacement of cement with 0, 0.5,1.0 %, and 1.5 % of steel fiber (SF). The findings demonstrated that concrete sustainability could be improved by employing VA as a partial replacement for cement, resulting in improved mechanical performance with a slight reduction in workability. The optimum mechanical and microstructure properties of SFVC were achieved with the incorporation of 5 % VA instead of cement with 1 % steel fiber, at age 28 days. The increase in compressive strength and tensile strength up to 25 % and 31 %, respectively. The employing of VA as a SCMs material resulted in better ITZ between aggregate and cement mortar and exhibited a dense surface with less pores compared to control mix.

Mechanical Properties of Cement Concrete with Waste Rubber Powder

To investigate the mechanical properties of cement concrete incorporating waste rubber powder, the response surface methodology was employed. The Box–Behnken central composite design was applied to analyze the three primary factors influencing the road performance of cement concrete containing waste rubber powder: the water–cement ratio, sand ratio, and waste rubber powder content. The study determined the impact of these factors on the flexural strength of waste rubber powder cement concrete at both 7 and 28 days. Additionally, the effects of the water–cement ratio, sand ratio, and waste rubber powder content on the performance of cement concrete were analyzed. To investigate the impact of waste rubber powder on cement concrete, various mechanical property tests were conducted, including compressive, flexural, dynamic elastic modulus, and impact performance tests. Furthermore, the study explored the influence of waste rubber powder on the noise reduction capacity of cement concrete using both the rubber ball impact method and ultrasonic method. Lastly, the durability of cement concrete with added rubber powder was assessed through shrinkage tests, frost resistance tests, and chloride ion penetration tests.

Improving geopolymer concrete performance with hazardous solid waste phosphogypsum

Recycling the hazardous solid waste phosphogypsum (PG) in concrete is a popular trend. However, the inherent properties of PG used alone in concrete tend to limit the strength of the concrete. In this study, PG was used as a precursor for the production of phosphogypsum-based geopolymer concrete (PGC), which effectively improved the performance of geopolymer concrete by utilising the synergistic effect of different solid wastes in geopolymer concrete. The effects of PG content (0, 10, and 20 %) and alkali modulus (0.8, 0.95, 1.1, and 1.25) on the axial compressive properties and resistance to chloride penetration of PGC were investigated. The results show that 10 % PG improved the properties of geopolymer concrete the most, with a maximum increase in axial compressive strength of 17 %. Due to the addition of SO42−, the PG content also affected the optimal alkaline modulus of PGCs. Chemical composition and microstructural analyses revealed that the promotion of the geopolymer reaction by PG is crucial for PGC performance enhancement. In addition, leaching tests and carbon emission assessment, confirmed that PGCs are an environmentally friendly option. Based on the analysis of axial compression behaviour, resistance to chloride ion permeability and environmental impact, PGC with 10 % PG content and 1.1 alkali modulus is an environmentally friendly alternative to conventional concrete. This study shows that hazardous solid waste PG can improve the performance of geopolymer concrete and create a new type of solid waste concrete.

Multiscale insights on compression cast sea sand and seawater concrete

Reinforced concrete (RC) structures in coastal and marine regions face two primary challenges, the shortage of raw materials and severe service environments. Concrete made from sea sand and seawater (SS-SW) can address the shortage of natural sand by utilizing locally available resources. Meanwhile, the newly developed compression cast technology (CCT) significantly improves the micro and macro properties of concrete, enhancing its durability in harsh environments. Therefore, the combination of SS-SW concrete and CCT to form a new compression-cast SS-SW concrete can simultaneously solve the problems of materials shortage and durability issues for coastal RC structures. However, till now, research on this type of concrete is still an open issue. This paper aims to carry out multilevel investigations on the macro and micro performance of compressed SS-SW concrete. First, 69 concrete columns were tested to understand the stress-strain behavior and associated mechanical indices. The compressive strength of compressed concrete was found to be up to 1.86 times greater than that of uncompressed concrete. Meanwhile, the porosities in both mortar and the interfacial transition zone (ITZ) of concrete under a casting pressure of 15 MPa were approximately 50 % of those in uncompressed counterpart. Existing models are inadequate for predicting the behavior of compressed SS-SW concrete, leading to the development of new and accurate models to predict its compressive strength, elastic modulus, peak strain and stress-strain curve. These findings pave the way for the design and application of this kind of concrete.

Study on printability of 3D printing carbon fiber reinforced eco-friendly concrete: Characterized by fluidity and consistency

Carbon fibers have often been added to concrete as reinforcement. Eco-friendly concrete with industrial by-products has been widely studied and applied as green building materials. Studying the workability and printability of eco-friendly concrete with carbon fibers is worthwhile. The workability and printability of eco-friendly concrete are dominating factors that ensure that printing can be carried out smoothly. This study uses a combination of experiments and numerical simulations to study the printing performance of carbon fiber-reinforced eco-friendly concrete (CFREFC). The workability and printability of 9 mixes of 3D printing CFREFC under various combinations of different water-binder (w/b) ratio levels and superplasticizer (SP) dosages were tested. Two methods, namely the consistency and fluidity tests, were used to characterize the printability. After consistency and mortar fluidity tests, the 9 mixtures were printed to get the printing performance. Finally, the relationship between the workability and printability of 3D printing CFREFC was established. The condition numbered M7 (w/b = 0.4, SP = 0.5) in the selected experimental group was used as the source of its simulation parameter. The result shows that it is feasible to characterize printability using workability, i.e., consistency and fluidity, which increase with the increase of w/b and SP dosage. Under the printing parameters of the HC1008 printer were determined, i.e., 20 mm of nozzle size, 50 mm/s of printing speed, 30 rpm of material extrusion speed, and 14 mm layer height, the fresh CFREFC was not suitable for 3DP application when its consistency is less than 48.99 mm and more than 81.96 mm, or when its fluidity is less than 166.72 mm and more than 200.93 mm. When the consistency is from 56.34 to 65.61 mm, and the fluidity is from 172.18 to 183.30 mm, the printability of CFREFC is the best under the same printing parameters. The simulation results indicated that with the increased number of printing layers, the bottom of the printed model would be deformed by the gradual increase in pressure, and a specific height loss would occur, which was consistent with the experimental results.

Full-scale test on the mechanical behavior of longitudinal joints of NC-UHPC composite segments under compression-bending load

The performance of longitudinal joints in shield tunnel segments is crucial for ensuring structural stability and durability. This study presents an innovative segment structure combining normal concrete (NC) and ultra-high performance concrete (UHPC) (hereafter called NC-UHPC composite segment). Full-scale joint tests were conducted to analyze the mechanical response and failure characteristics of longitudinal joints in these segments. Compared to reinforced concrete (RC) segment joints, NC-UHPC composite segment joints exhibited a significant increase in initial cracking load by 197.93% under sagging moments and 435.3% under hogging moments. The ultimate load-bearing capacity increased by 55.71% and 67.10%, and the initial bending stiffness improved by 20.57% and 10.59% under sagging and hogging moments, respectively. Furthermore, NC-UHPC composite segment joints exhibited smaller crack distribution areas and fewer cracks, indicating superior crack resistance. No cracks or damage were observed at the NC-UHPC interface. Evaluation of joint toughness and ductility indices further highlighted the favorable performance of NC-UHPC composite segment joints. Finally, a refined numerical model was established to compare the deflection and bending stiffness of RC segment joints with NC-UHPC composite segment joints under varying axial forces. The findings suggest that NC-UHPC composite segments are more suitable for tunnel engineering with greater burial depth, higher water pressure, and larger axial forces.

Electric heating curing regimes of temperature self-controlled concrete with nano-carbon black for performance improvement in cold regions

Temperature self-controlled concrete (TSC) demonstrates excellent electric heating performance, providing an effective solution for on-site curing of concrete in cold regions. A suitable electric heating curing (EHC) regime can lead to a desired internal temperature to facilitate the hydration of cement under negative temperature environment and improve the performance of concrete. This study prepared the TSC by adding nano-carbon black into ordinary concrete and investigated the effects of 2 different types of EHC regime, namely constant voltage curing (CVC) and ascending voltage curing (AVC) regimes, on the mechanical properties, electrical properties, temperature evolution, microstructure, and carbon emissions. The results demonstrate that samples cured using traditional methods exhibit the lowest strength. In contrast, the application of EHC shows significant advantages in negative environments compared to traditional curing methods. TSC cured under AVC regimes exhibits a 21.3 % and 33.4 % increase in compressive strength, as well as a 4.4 % and 20.8 % increase in splitting tensile strength at 3 days and 7 days, respectively, compared to TSC cured under CVC regimes. AVC effectively reduces peak temperature and temperature difference, and leads to the peak temperature shifting backward. Additionally, the hydration products of TSC cured under AVC regimes are fewer. However, AVC regimes promote stable microstructural development, favorable resistivity of TSC, and result in a lower carbon footprint during the curing period. The research findings highlight the superiority of AVC regimes in negative temperature environments, potentially addressing challenges in in-situ curing of concrete structures in cold regions and improving efficiency in prefabricated component production.

Study on Basic Pavement Performance of High-Elasticity Asphalt Concrete.

In order to improve the basic pavement performance of high-elastic asphalt concrete filled in the expansion longitudinal joints of seamless bridges, rubber particles and polyester fibers were added to optimize the mix proportion of elastic asphalt concrete, and the optimal asphalt-aggregate ratio was determined. The influence of rubber particles and polyester fibers on the basic pavement performance of high-elastic asphalt concrete was studied. The results show that when the dosage of polyester fiber is not more than 0.6%, the optimal asphalt-aggregate ratio is 1:5, and when it exceeds 0.6%, the optimal asphalt-aggregate ratio is 1:4. The incorporation of rubber particles reduces the compressive strength of high-elastic asphalt concrete but enhances its high-temperature stability, fracture performance, and deformation recovery ability. The incorporation of polyester fibers improves its compressive strength, high-temperature stability, fracture performance, and deformation recovery ability. In addition, the incorporation of rubber granules and polyester fibers promotes the use of green building materials and provides strong support for sustainable building practices.

An Integrated Hydration and Property Evaluation Model for Coral Powder–Cement Binary Blends

With the rise in the marine industry and marine tourism, coral powder is increasingly used to make concrete for marine islands. This study proposes a three-parameter hydration model and a hydration kinetic model to predict the performance of coral powder concrete based on previous experimental data. The process of the proposed prediction model is as follows: 1. The input parameters of the three-parameter hydration model are calibrated for the first 7 days using the cumulative hydration heat per gram of cement. The maximum cumulative hydration heat (455.87 J/g cement) and the shape coefficient (−0.87) remain constant. In this study, the hydration rate coefficients for 0%, 10%, and 20% coral powder were 6.91, 6.19, and 5.55, respectively, showing decreases of 10.41% and 19.68% compared with the specimens without coral powder. 2. At 28 days, the cumulative heat release values per gram of cement for 0%, 10%, and 20% coral powder were 389.77, 395.69, and 401.62 J/g, showing increases of 1.52% and 3.04% for the specimens containing 10% and 20% coral powder, respectively. Meanwhile, the hydration degrees for 0%, 10%, and 20% coral powder were 0.855, 0.868, and 0.881, respectively, showing increases of 1.52% and 3.04%. Furthermore, the cumulative heat release values per gram of binder were 389.77, 356.12, and 321.29 J/g, showing decreases of 8.63% and 17.56% for specimens containing 10% and 20% coral powder, respectively. 3. Properties such as compressive strength, ultrasonic pulse velocity (UPV), and surface electrical resistivity were evaluated using the power function and the cumulative hydration heat per gram of binder. 4. At 28 days, the chemically bound water contents for samples with 0%, 10%, and 20% coral powder were 0.2402, 0.2197, and 0.1981 g/g binder, respectively. Moreover, the calcium hydroxide contents were 0.1848, 0.1690, and 0.1524 g/g binder, showing reductions of 8.53% and 17.52% in bound water and 8.54% and 17.53% in calcium hydroxide. 5. A hydration kinetic model is proposed, which can distinguish between the dilution effect and the nucleation effect of coral powder, unlike the three-parameter model, which cannot distinguish between the two effects. Furthermore, the input parameters of the hydration kinetic model remain unchanged for different mixtures, while the input parameters of the three-parameter model must be varied among mixtures. Parameter analysis of the hydration kinetic model indicated that a low water–binder ratio and a high coral powder substitution rate significantly improve the relative reaction level of cement.

Effects of general and saturated humidity on concrete performance deterioration under sulfur dioxide attack

A large amount of SO2 is emitted with the rapid development of industrialization, and there are big differences in the deterioration of concrete subjected to SO2 attack between the environments of general humidity and saturated humidity. This paper conducted the simulation tests of concrete subjected to SO2 attack at general humidity (RH = 80 %) and saturated humidity (RH = 98 %), and the sulfuration depth, mass, and compressive strength were comparatively studied. The distributions of pore-solution pH and SO2- 4 concentration of concrete at different exposure times and depths were analyzed, and the deterioration mechanisms on concrete under SO2 attack in these environments were compared. The results indicated that the sulfuration depth and mass remained unchanged in the middle and later periods of the attack at 80 % RH, and the compressive strength at 20d was still larger than that before SO2 attack. However, the sulfuration depth and mass increased rapidly at 98 % RH, and the compressive strength loss rate was 18.80 % at 20d. The ions concentrations at 98 % RH changed greatly with increasing exposure time, and the pH and SO2-4 concentration of concrete at 1 mm at 20d were 2.41 times less and 3.86 times larger than those at 80 % RH, respectively. The initial product at 80 % RH was ettringite, which converted to gypsum with the progress of SO2 attack, and these expansive products decreased the porosity of concrete. A large amount gypsum was produced at 98 % RH, leading to the initiation and propagation of microcracks, and the porosity increased to 41.43 %.

Enhancing Performance and Reducing Environmental Impact of Concrete with Replacement of Recycled Concrete Aggregate Treated with Various CO2 Pressures

Enhancing Performance and Reducing Environmental Impact of Concrete with Replacement of Recycled Concrete Aggregate Treated with Various CO₂ Pressures

Machine learning-based technology for asphalt concrete pavement performance decision-making in hot and humid climates

Highway state agencies incur significant budget savings through optimal allocation of pavement Maintenance, Rehabilitation, and Reconstruction (MR&R) activities. These activities require robust prediction models that can handle large-scale, real-world data and can forecast pavement performance in the long run. Unfortunately, the traditional performance prediction models have been questionable in terms of efficiency and accuracy, are based on a limited number of explanatory variables, and are designated to predict short-term (up to five years) pavement conditions. Therefore, the goal of this study was to propose a machine learning-based technology that can predict the field performance by up to 11 years of Asphalt Concrete (AC) overlays placed on asphalt pavements in Southern states in the US based on key project conditions. The proposed technology resulted from assessing the prediction accuracy of machine learning algorithms, including Decision-Tree (DT), eXtreme Gradient Boosting (XGBoost), Artificial Neural Network (ANN), and ensemble-learning method, in forecasting the Pavement Condition Index (PCI) as the pavement performance indicator. For each algorithm, six models were developed sequentially based on historical pavement condition data collected from the Louisiana Department of Transportation and Development (LaDOTD) Pavement Management System (PMS) database. The six models learned from 892 log miles of randomly placed AC overlay sections in Louisiana. The output of these models was the future PCI of AC overlays at a biannual rate from one to 11 years. The findings showed that XGBoost and ensemble learning showed similar performance during model training and were further evaluated using the testing dataset. During model testing, the ensemble learning method yielded higher prediction accuracy than other algorithms, with R2 values decreasing from 0.77 at age 1 to 0.67 at age 11, Root Mean Square Error (RMSE) values increasing from ±1.65 to ±4.74, and Mean Absolute Error (MAE) increasing from 1.24 to 4.59. The resulting models can be used by state agencies to replace traditional prediction techniques.

Effect of Graphene Quantum Dots (GQDs) on the mechanical, dynamic, and durability properties of concrete

Addressing ecological concerns stemming from concrete usage is paramount, prompting exploration into additives for mitigation. Graphene quantum dots (GQDs) have been recognized for their potential to improve the mechanical attributes of cement composites. Additionally, the electrochemical reduction of a saturated solution of carbon dioxide (CO2) and monoethanolamine (CO2-MEA) effectively removes CO2 from the atmosphere. This study delves into the influence of GQDs on the mechanical and durability aspects of concrete. It is noted that the control mix of concrete without GQDs was specifically designed for concrete railway sleepers. Varied proportions of GQDs, ranging from 0.3 % to 1.2 % at 0.3 % increments, were incorporated to assess their impact on fresh and hardened concrete properties. Mechanical properties such as compressive strength, splitting tensile strength, flexural strength, and dynamic properties were evaluated. Durability assessments encompassing water absorption and chloride ion penetration were conducted. Microstructural analysis via Field Emission Scanning Electron Microscopy (FESEM) imaging and Energy-dispersive X-ray spectroscopy (EDS) elucidated the concrete's internal composition. Notably, an optimal GQDs percentage of 0.3 % was observed, signifying its efficacy in enhancing the performance of concrete. When 0.3 % of GQDs was added to concrete, compressive strength, split tensile strength, and flexural strength were enhanced by 10.8 %, 23 %, and 11 % respectively. The incorporation of GQDs resulted in a notable improvement in the fundamental frequencies and dynamic modulus of elasticity. Concurrently, a decrease in the damping ratio was observed for specimens containing GQDs. Additionally, the porosity and chloride penetration depth were lower by 6 % and 30 % for specimens with 0.3 % GQDs. The improvement in workability, mechanical, and dynamic properties of concrete, along with reducing CO2 from the atmosphere, makes GQDs an ideal eco-friendly material. This study is the first to open new pathways for the development of construction materials that are not only structurally superior but also environmentally responsible, marking a significant step forward in the field of civil engineering materials, especially in railway applications.

Assessment of crack repairing in concrete using air-coupled surface-wave technique: Experimental and numerical investigations

This study aimed to investigate the effectiveness of air-coupled surface-wave techniques for the evaluation of crack-repairing (filling) progress in concrete. Experimental tests were performed on four lab-scale slab-shaped concrete specimens for their uncracked, cracked, and repaired conditions. A structural crack with 0.6- to 0.7-mm wide at the mouth was generated at the midspan of each specimen. The specimen was repaired using an epoxy injection method, and the hardening progress of the injected epoxy was monitored by surface wave measurements for the following 24 hours. Finite element analyses were performed as well to simulate the crack-repairing process by changing the elastic modulus of the repaired zone and quantify the surface wave transmission across the repaired crack. The experimental results revealed that the surface-wave transmission ratio in the fully repaired specimen was recovered up to 90.5 % of the uncracked condition. The numerical analysis showed that, when the elastic modulus of the repaired crack zone reached approximately one-tenth of that of concrete assuming fully-hardened epoxy, the surface-wave transmission ratio was recovered up to approximately 90 % of the uncracked condition. These results imply that air-coupled surface-wave techniques are deemed effective for evaluating crack-repairing performance in concrete.

Performance of the bond between recycled concrete and steel bars subject to transverse stirrup constraints after exposure to high temperatures

This study investigates and assesses the bond performance between steel reinforcement and recycled concrete, subject to the confining effect of transverse stirrups post high-temperature exposure. A series of 24 specimen groups was examined, with variations in parameters including transverse stirrup ratios (0 %, 0.24 %, 0.67 %, 1.34 %), recycled concrete aggregate (RCA) replacement ratios (0 %, 50 %, 100 %), and temperatures (300 °C, 500 °C, 700 °C). Central pull tests were administered to discern the impact of each parameter on the bond integrity of steel-reinforced recycled concrete. The results revealed that high temperatures reduced the thickness of the critical cover, altering the failure mode of the specimen. With rising temperatures, the bond strength of steel-reinforced recycled concrete weakened. Nonetheless, an increase in stirrup ratio served to counteract the detrimental effects of high temperatures. In contrast, a higher RCA replacement ratio exacerbated these effects. For example, specimens with a 1.34 % stirrup ratio showed a 30 % decrease in the adverse impacts of high temperature on bond strength compared to those with no stirrups. A comprehensive computational model, devised from experimental data and theoretical analysis, predicts the bond-slip behavior of steel-reinforced recycled concrete, incorporating the constraint coefficient k, temperature T, and replacement ratio r as pivotal parameters. The model’s predictive curve corresponds closely with the experimental findings, effectively capturing the influence of high temperature, lateral restraint, and RCA replacement ratio on the bond performance of steel-reinforced recycled concrete.

Influence of Manufactured Sand on Fresh Properties, Strength Properties and Morphological Characteristics of Self-Compacting Coconut Shell Concrete

This research examines the fresh properties, strength performance, and morphological analysis of self-compacting coconut shell concrete (SCCSC) blended with crushed coconut shell and manufactured sand (M-sand). Crushed coconut shell (CS) was used as a coarse aggregate (CA), and M-sand replaced river sand (R-sand) at 25%, 50%, 75%, and 100%. The study focused on the workability characteristics, mechanical behavior, and microstructural analysis of SCCSC. Experiments were performed on fresh and mechanical characteristics, including slump flow diameter, T500 slump flow time, L-Box blocking ratio, V-funnel and a wet sieving stability test. Mechanical characteristics include compressive, split tensile, flexural, impact resistance and bond strength. Utilizing M-sand develops the mechanical performance of SCCSC. The morphological characteristics, using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), Fourier transform infrared (FTIR) and the X-ray diffraction (XRD) technique, were studied in this research work. The findings show that the addition of M-sand increases the concrete strength. The microstructural analysis demonstrates that adding different amounts of M-sand to SCCSC reduced the porosity and anhydrous cement percentage, although it increased calcium hydroxide and hydration products. The substitution of 100% M-sand at 28 days increased compressive strength by 3.79% relative to the reference SCCSC. Based on the findings, the mechanical strength of SCCSC containing M-sand significantly improved compared to the concrete with river sand.

Speech-Gesture Matching and Schizotypal Traits: A Network Approach.

Impaired speech-gesture matching has repeatedly been shown in patients with schizophrenia spectrum disorders. Here, we tested the hypothesis that schizotypal traits in the general population are related to reduced speech-gesture matching performance and reduced self-reports about gesture perception. We further explored the relationships between facets of schizotypy and gesture processing in a network model. Participants (1094 mainly healthy adults) were presented with concrete or abstract sentences accompanied with videos showing related or unrelated gestures. For each video, participants evaluated the alignment between speech and gesture. They also completed self-rating scales about the perception and production of gestures (Brief Assessment of Gesture scale) and schizotypal traits (Schizotypal Personality Questionnaire-Brief 22-item version). We analyzed bivariate associations and estimated a non-regularized partial Spearman correlation network. We characterized the network by analyzing bridge centrality and controllability metrics of nodes. We found a negative relationship between both concrete and abstract gesture-speech matching performance and overall schizotypy. In the network, disorganization had the highest average controllability and it was negatively related to abstract speech-gesture matching. Bridge centralities indicated that self-reported production of gestures to enhance communication in social interactions connects self-reported gesture perception, schizotypal traits, and gesture processing task performance. The association between impaired abstract speech-gesture matching and disorganization supports a continuum between schizophrenia and schizotypy. Using gestures to facilitate communication connects subjective and objective aspects of gesture processing and schizotypal traits. Future interventional studies in patients should test the potential causal pathways implied by this network model.

Study on the Effect of XYPEX Admixture on the Performance of Panel Concrete and Microscopic Mechanism

The influence of different XYPEX content on the performance of dam panel concrete was studied through laboratory tests. The test results show that a certain amount of XYPEX can improve the compressive strength and impermeability of panel concrete. According to the scanning electron microscope photos, XYPEX admixture has a good filling effect on the internal pores of concrete in the microstructure, and the macro performance is improved for impermeability, but the effect on the visible cracks on the surface of concrete is small. The research results fill the gap in the research field of XYPEX admixture in dam panel concrete, provide a new idea for improving the durability of panel concrete, and provide technical support and data support for the future application of XYPEX admixture in water conservancy and hydropower projects.

Investigation on Properties of Pervious Concrete Containing Co-Sintering Lightweight Aggregate from Dredged Sediment and Rice Husks

The utilization of dredged sediment (DS) as a transformative material in building applications presents an ideal consumption strategy. This study endeavors to create a novel ceramsite lightweight aggregate (LWA) through the co-sintering of DS and rice husks (RHs), further integrating this LWA into the construction of pervious concrete. Results revealed that the optimum production procedure for the DS-based LWA incorporated a 21% RH addition, a sintering temperature of 1100 °C, and a sintering duration of 21 min. Notably, the optimal ceramsite LWA, denoted as SDC-H, exhibited a cylinder compressive strength of 28.02 MPa and an adsorption efficiency for Pb2+ of 94.33%. Comprehensive analysis (encompassing bulk density, cylinder compressive strength, water absorption, and the leaching concentrations of heavy metals) confirmed that SDC-H impacted the specification threshold of high-strength light aggregate derived from solid waste (T/CSTM 00548-2022). Substituting 50% of SDC-H led to a diminution in the mechanical properties but an improvement in the dynamic adsorption capacity of the innovative pervious concrete, registering a mechanical strength of 26.25 MPa and a cumulative adsorption capacity for Pb2+ of 285 mg/g. These performances of pervious concrete containing 50% SDC-H might correlate with the evolution of an interconnected and open-pore structure.