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This study aimed to investigate the shear performance of composite beams with prefabricated U‐shaped reactive powder concrete (RPC) permanent formworks with normal strength concrete poured inside. Three‐point bending tests were performed on eight composite beams with prefabricated U‐shaped RPC‐reinforced formworks and one reinforce concrete beam. Additional parameters, such as the stirrup spacing, shear span ratio, and inner core concrete strength, were evaluated. The test results indicated that the prefabricated U‐shaped RPC permanent formworks increased the shear capacity of the composite beams. Under the same configuration, the bending cracking load, stirrup yield load, and peak load of the composite beams increased by 51.54%, 88.02%, and 78.38%, respectively. An analytical model was proposed to predict the shear strength of composite beams with prefabricated U‐shaped RPC formwork and validated using the experimental results. [ABSTRACT FROM AUTHOR]

Calculation model for thermal pre‐stressing of subsequently added reinforcement Key technical limitation of many strengthening measures is that they are not effective for the structure's self‐weight. As a solution, a targeted tempering of reinforcing bars put into respective slots is proposed for statically determinate load‐bearing structures. The aim is to thermally pre‐stress the bars, which are embedded in a grouting material, and to balance their strain to that of the initial reinforcement. The bond with the grout prevents the bars from re‐forming when cooling after heating is stopped. This creates pre‐stress that neutralizes the bending moment from the self‐weight and relieves the tensile zone of the cross‐section. In the paper, an analytical calculation model for the strengthening approach is presented and derived. This is verified through numerical calculations and a first experimental realization. The main factors influencing the effectiveness of the strengthening measure are analyzed in parameter studies. The results show that the thermal pre‐stressing of subsequently added reinforcing bars is effectively possible. Depending on the actual boundary conditions, the calculation predicts the strengthening effect with an accuracy of 80–97 %. The accuracy increases with the height and a lower initial temperature and a lower thermal conductivity of the concrete in the initial cross‐section. [ABSTRACT FROM AUTHOR]

To develop an efficient internal force calculation model for double row anti-slide piles with connecting beams, the finite difference method was used to calculate the internal force of all piles at the load section and embedded end of double row piles. The structure of double row anti-slide pile with connecting beam was simplified to two single piles disconnected at the zero bending moment of the connecting beam at the pile top; the bending moments and shear forces at the top of the front and back piles were obtained by superposition of the forces on the double row piles. The structural model tests were carried out to check the effectiveness of the calculation model based on the finite difference method. The results show that the model test results are consistent with the data of pile top displacement and pile body bending moment obtained from the calculation model, indicating that the simplified calculation model is effective. There is a slight deviation between the positions where the maximum bending moment calculation is for the rear pile. The calculated maximum bending moment position is close to the real pile failure position, further proving the reliability of the entire pile internal force calculation model based on the finite difference method. The finite difference calculation model avoids the complex calculation process of iterating the loaded and embedded sections using continuous conditions, and provides a fast and efficient method for calculating the internal forces of double row piles with connecting beams in practical engineering.

Copyright of Iron Steel Vanadium Titanium is the property of Iron Steel Vanadium Titanium Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the structural and geological characteristics of the F1 weathering trough of a submarine tunnel and its spatial relationship with the cavern, a simplified calculation model of the weathering trough water inrush was established, and the formation, development process and influencing factors of the water inrush channel in the water-resistant rock layer were carried out by a numerical simulation of particle flow. It shows that the integrity and stability of the critical water-resistant rock mass is the key to preventing water inrush, and the identification and positioning of the water inrush channel is the basis for the grouting reinforcement design of the weathering groove of the submarine tunnel. Based on above research results, the F1 weathering trough was blocked and reinforced by the composite grouting method, and the engineering reinforcement effect was good. [ABSTRACT FROM AUTHOR]

Increasing stockpile of scrap rubber tires imposes a serious threat to the safety of surrounding ecological environment. Rubber particle of excellent thermal insulating properties with comparison of granular soils makes it an ideal candidate for developing sustainable construction materials. While thermal conduction behaviors of rubber-sand mixtures have not been clearly revealed. Several series of thermal probe tests were conducted on scrap rubber tire-sand mixtures with varied rubber contents, moisture contents, and dry densities. A predictive model was proposed by resorting to the artificial neural network technology to capture the thermal conductivity data. The results showed that an obvious decrease in thermal conductivity is taken after the addition of rubber, and the decreasing rate is related to moisture content of mixtures. The presence of pore water is beneficial to the improvement of thermal conductivity. The critical moisture content of investigated rubber-sand mixtures is approximately 8 %, further increase in moisture content leads to a faint increment of thermal conductivity. Rubber-sand mixtures of high dry density have good particle contact behaviors, exhibiting a high thermal conductivity value. The influences of rubber content, moisture content, and dry density on thermal conductivity are intertwined together that should be comprehensively analyzed. The developed model exhibits satisfactory accuracy for thermal conductivity prediction, as reflected by correlation coefficient higher than 85 % and relative error being controlled under 10 %. Additional study is recommended to evaluate the thermo-mechanical behaviors and durability of rubber-soil mixtures. The outcomes of this study provide one of available answers for reusing scrap rubber tire in engineering fields.

A single-row pile dam is a type of rigid debris flow barrier structure. In order to reveal the mutual interaction effects between debris flow and a single-row pile dam and the distribution law of debris flow impact forces, an analysis of the correlation between debris flow density, characteristic particle size, and relative pile spacing (the ratio of pile gap size to debris flow characteristic particle diameter) and debris flow impact forces was conducted to obtain dimensionless parameters related to debris flow impact force and climbing height. These parameters were verified through flume model experiments to provide theoretical support for the engineering design of single-row pile dams. The results show that the impact force of the debris flow on the pile dam is mainly affected by the flow velocity, debris flow density, and relative pile spacing. The dimensionless parameters are introduced, and the semi-empirical expression of the impact load coefficient is established. The impact pressure coefficient of debris flow is classified into two categories, and the calculation model of impact load of a single-row pile dam is constructed. The research results can provide a theoretical basis and technical parameters for designing a single-row pile dam.

The generalized model and parameter equation for the internal fracture surface of tensile type anchor cable anchorage section are constructed, and the calculation model of ultimate bearing capacity is derived based on the principle of limit equilibrium. The shape of the internal fracture surface in the anchorage section and the expression of its parameter equation are experimentally studied, and the variation law of the parameter equation and fracture range with the diameter of the anchor cable and confining pressure is analyzed. The parameter equation is substituted into the calculation model to realize the calculation and verification of the model. Through theoretical derivation, a calculation model of ultimate bearing capacity of anchor cable is obtained, which comprehensively considers the average shear strength of anchorage section, the shape of fracture surface, fracture range and confining pressure. The tests show that according to the magnitude of the confining pressure on the anchorage section, the internal fracture surface takes on two shapes: cylindrical and trumpet‐shaped, the parameter equation of trumpet‐shaped fracture surface obeys logarithmic distribution approximately. The coefficient a decreases with the increase of confining pressure but increases with the increase of anchor cable diameter, the constant b increases with the increase of confining pressure but decreases with the increase of anchor cable diameter. The ranges of horizontal and vertical fracture decrease with the increase of confining pressure, and increase with the increase of anchor cable diameter. The deviations between the theoretical calculation and the experimental results are less than 6.5%. [ABSTRACT FROM AUTHOR]

In order to ensure accurate spraying of pesticides and reduce the loss of pesticides in fruit trees, a calculation model of precise pesticide spraying quantity in orchards was established. The model included the canopy parameters, interface properties of the fruit tree, and the pesticide destination in the orchard, which could be used to guide the modes of spraying for different plant protection machinery under different planting patterns in the orchard. By selecting 'Fushi' apple leaves of different phenological periods as research objects, the leaf surface free energy and canopy parameters were tested. The relationship between liquid surface tension and maximum liquid holdup was established for apple leaves. The maximum pesticide loading of the whole tree was calculated based on maximum liquid holdup and canopy parameters. The calculation model of precise pesticide spraying quantity was established, combined with the pesticide destination in the orchard. The application of two kinds of spraying machines, stretcher plunger pump sprayer in the low-density planting orchard and selfpropelled axial flow sprayer in the close planting orchard, were taken as examples, and the practicability of the model was verified. The results showed that the use of a stretcher plunger pump sprayer in the early stage in the low-density planting orchard could save 37.40% of liquid compared with the original, and 18.75% of liquid could be saved in the later stage. The use of a self-propelled axial flow sprayer in the late stage of the close planting orchard can save 28% of the liquid. There was no significant difference between the control efficacy and the dosage of conventional liquid medicine. This model combined the interface properties of apple leaves with the application equipment could not only calculate accurately the spraying amount of pesticide according to the actual situation of the orchard， but also evaluate the applicability of pesticide liquid at a certain period. The mode could adjust the parameters of the pesticide liquid and spray machine according to the actual situation, so as to achieve the purpose of precise pesticide application. [ABSTRACT FROM AUTHOR]

Engineered cementitious composites (ECCs) have ultrahigh ductility and multiple-cracking properties. High-strength stainless steel wire rope (HSSSWR) has high tensile strength and good corrosion resistance. Taking advantage of these two materials, ECCs reinforced with HSSSWR (HSSSWR-ECCs) promise to be attractive when used in flexible and ductile link slabs in bridge deck systems, in permanent formworks of concrete members and for strengthening existing members. In this work, bending tests were performed on HSSSWR-ECC slabs with different HSSSWR reinforcement ratios and ECC formulations. The results showed that the HSSSWR-ECC slabs exhibited excellent crack-width control and deformation capacities under bending moments. An increase in the HSSSWR reinforcement ratio enhanced the flexural capacity of the HSSSWR-ECC slabs, but reduced their ductility. Adding a thickener to the ECC enhanced the crack-width control ability and ductility of the HSSSWR-ECC slabs by improving the dispersion of polyvinyl alcohol fibres in the ECC, but reduced the flexural capacity by reducing the strength of the ECC. Formulas for predicting the flexural capacity of HSSSWR-ECC slabs were developed based on related mechanics theories. The accuracy of the proposed formulas was verified by comparing the test results and predicted results using a finite-element model for HSSSWR-ECC slabs. [ABSTRACT FROM AUTHOR]

Both foam and bentonite slurry are commonly employed in soil conditioning to prevent water spewing during earth pressure balance (EPB) shield tunnelling. A novel calculation model to estimate the permeability coefficient of soils conditioned with foam and bentonite slurry is developed. In this model, bentonite particles are assumed to adhere to the foam film in a monolayer of bridging particles, and the permeation channels within the conditioned soil are updated using the Kozeny-Carman equation. A series of permeability tests on conditioned soil, varying conditioning parameters and water heads, validate the accuracy of the model. The measured results that the value of permeability coefficient can be well captured by the calculation results, which indicates that the model can accurately predict the permeability of soil conditioning by foam and bentonite slurry. While there is a slight reduction in accuracy for conditioning states with high foam and bentonite slurry injection ratios, the model remains conservative for tunnelling engineering safety due to calculated values consistently exceeding measured ones. Furthermore, the model performs well in cases of foam-conditioned soil from previous studies. Additionally, the model underscores the significant influence of bentonite slurry on the permeability coefficient by altering soil grain gradation. [ABSTRACT FROM AUTHOR]

This study conducted four-point bending tests on plates to investigate the effect of natural wollastonite microfiber (WF) on the flexural behaviors of three types of ultra-high performance concrete (UHPC): mono WFs reinforced UHPC (WF-UHPC), mono steel macrofibers (SFs) reinforced UHPC (SF-UHPC), and hybrid SFs and WFs reinforced UHPC (WFMUHPC). Meanwhile, the compressive and splitting tensile strengths of the specimens were also tested. The results showed that WF could significantly improve the compressive strength, splitting tensile strength, first crack flexural strength (fcr), peak flexural strength (fpeak), peak toughness (Ωp) and flexural toughness (Ωm) of UHPC matrix and SF-UHPC. When SF content was greater than 1.5 vol%, fpeak of SF-UHPC and WFMUHPC no longer showed a significant increase, and even presented a decrease in Ωp and Ωm, which was related to the group effect of SFs and wall effect. Digital camera (DC) test results showed that WF could deflect cracks. WFMUHPC with 1.5 vol% of SFs and no more than 9 vol% of WFs exhibited excellent multi-crack characteristics. Scanning electron microscope (SEM) test demonstrated that WF could bear the internal stress, be pulled out or fracture, and have filling effect on matrix. Based on composite theory, the calculation models of fcr and fpeak of UHPC plates were established. [ABSTRACT FROM AUTHOR]

The results of experimental studies on attenuating neutron and photon radiation in a nuclear reactor using a protective metal hydride composite are presented. The distribution profile of the dose and spatial energy is obtained for primary and secondary gamma radiation. It is shown that the dose of gamma radiation behind the protection is associated with capturing gamma rays generated in the initial layer of the material. Based on the results obtained, the calculation model of the experiment is verified in the two-dimensional geometry for the properties of the material protecting the reactor. The verification involves the discrete ordinate method based on the DORT package. Deviations between the calculated and experimental values of the fast neutron relaxation lengths do not exceed 5%. The same deviations obtained for gamma radiation are under 7%, which confirms the validity of the calculation technique and the potential to apply the data obtained to proceed with designing radiation protection based on the metal hydride composite. [ABSTRACT FROM AUTHOR]

Historical reinforced concrete (RC) buildings are culturally and aesthetically significant and require conservation due to aging. Strengthening RC buildings often requires the use of Fiber Reinforced Polymer (FRP) sheets, however distinct material properties of historical RC buildings have not been systematically considered yet. This study investigates the flexural behavior of historical RC beams strengthened by hybrid FRP sheets. A total of 11 beam specimens with varying FRP sheet configurations were tested using a four-point bending test to assess their flexural behavior, including failure mode, cracking pattern, load-deflection behavior, strain distribution, and ductility. The results showed that hybrid FRP sheets increased the maximum bearing capacity of strengthened specimens up to 30.2 %. An optimal fiber sheet configuration (T-3) is identified. 45-degree incline installation contributes to a 4.5 % increase in the bearing capacity of specimens. The average ductility loss of hybrid FRP sheets strengthened specimen (except for double-layer strengthened specimen) is 42 %, while an increase of sheet layer post adverse effect on ductility. Strain distribution conforms to the plane-section assumption. Additionally, a maximum bearing capacity calculation model was proposed, aiding the understanding of FRP strengthening in historical RC buildings.

This paper deals with the verification of models for the calculation of the contact area with the soil using data measured during the testing of a tractor-and-trailer unit. The main emphasis was put on the method of calculating the contact area by means of a super ellipse. The comparison included calculation models with the input parameters of contact length and contact width of the tyre. These parameters were compared with values measured in the field where the main variables were tyre dimensions, inflation pressure and load. Results of comparisons show that the method of calculating the contact area using a super ellipse exhibited the best match with the measured values of all compared calculation models (81% in super ellipse with measured half-axes and 75% in super ellipse with calculated half-axes). As to trailer tyres, the match of measured values and those calculated using a super ellipse was even 95%. In the second step, also some empirical models for calculating the contact area were compared with the measured data, not entered by contact length and contact width as variables. Some of these models show a very good match with the measured data, which can be compared, or it is even higher than the calculation by means of a super ellipse. With the specified tyre deformation, however, we consider the model of calculation using a super ellipse as more appropriate for determining the size of contact area as it focuses on the geometry of tyre contact with the ground.

In the process of ion-adsorption rare earth ore leaching, the migration characteristics of the wetting front in multi-hole injection holes and the influence of wetting front intersection effect on the migration distance of wetting fronts are still unclear. Besides, wetting front migration distance and leaching time are usually required to optimize the leaching process. In this study, wetting front migration tests of ion-adsorption rare earth ores during the multi-hole fluid injection (the spacing between injection holes was 10 cm, 12 cm and 14 cm) and single-hole fluid injection were completed under the constant water head height. At the pre-intersection stage, the wetting front migration laws of ion-adsorption rare earth ores during the multi-hole fluid injection and single-hole fluid injection were identical. At the post-intersection stage, the intersection accelerated the wetting front migration. By using the Darcy's law, the intersection effect of wetting fronts during the multi-hole liquid injection was transformed into the water head height directly above the intersection. Finally, based on the Green-Ampt model, a wetting front migration model of ion-adsorption rare earth ores during the multi-hole unsaturated liquid injection was established. Error analysis results showed that the proposed model can accurately simulate the infiltration process under experimental conditions. The research results enrich the infiltration law and theory of ion-adsorption rare earth ores during the multi-hole liquid injection, and this study provides a scientific basis for optimizing the liquid injection well pattern parameters of ion-adsorption rare earth in situ leaching in the future.

According to the provisions on fire separation distance between industrial and civil buildings in the latest 'General Code for Fire Protection of Buildings and Constructions' (GB 55037-2022). Radiant heat intensity is one of the main factors in calculating the fire separation distance between buildings. Therefore, the design process involves a lot of calculation of radiant heat intensity. This paper mainly studies the prediction model of radiant heat flux. Three different view factor calculation models, Mudan, Mudan-Sparrow, and Rai-Kalelkar, are used to evaluate the influence of key factors such as the diameter of the pool and the distance between the target and the center point of the liquid pool on the calculation results of radiant heat flux. The results show that when it came to estimating the radiant heat flux, the Mudan and Mudan-Sparrow models yielded comparable results. The calculation of the Rai-Kalelkar model shows that the radiant heat flux is about half of the heat flux in the first two models. When calculating the minimum fire separation distance for combustible liquid storage tanks with a fire dike, the results show that all three models can provide a larger safety margin than the point source model.

In box jacking, injecting lubricant around the box is an essential method to reduce excessive friction forces caused by the interaction between the box and soil. This method introduces complexity to factors controlling the friction forces, such as the pipe-soil contact state, earth pressure, and friction coefficient. In particular, during long-distance construction, different lubricant conditions come into play. These intricate scenarios hinder the accurate estimation and control of friction force throughout the entire construction period. This study analyzed the variation patterns of frictional resistance based on monitoring data from two actual cases. The lubricant condition changes during the long-distance jacking process were categorized, the effect of lubricant actions on factors controlling friction force in each segment was discussed, and a new method for calculating friction forces by partitioning the long-distance box jacking was proposed. This approach aims to enhance the prediction accuracy and was compared with the results obtained from existing models. The rationality of the new model was further validated by combining numerical simulation results with field data. The results indicate that the proposed segmented calculation model demonstrates better prediction accuracy when facing variations in actual construction conditions. It can serve as a reference for the process design and construction control of long-distance box jacking. [ABSTRACT FROM AUTHOR]

This paper deals with the verification of models for the calculation of the contact area with the soil using data measured during the testing of a tractor-and-trailer unit. The main emphasis was put on the method of calculating the contact area by means of a super ellipse. The comparison included calculation models with the input parameters of contact length and contact width of the tyre. These parameters were compared with values measured in the field where the main variables were tyre dimensions, inflation pressure and load. Results of comparisons show that the method of calculating the contact area using a super ellipse exhibited the best match with the measured values of all compared calculation models (81% in super ellipse with measured half-axes and 75% in super ellipse with calculated half-axes). As to trailer tyres, the match of measured values and those calculated using a super ellipse was even 95%. In the second step, also some empirical models for calculating the contact area were compared with the measured data, not entered by contact length and contact width as variables. Some of these models show a very good match with the measured data, which can be compared, or it is even higher than the calculation by means of a super ellipse. With the specified tyre deformation, however, we consider the model of calculation using a super ellipse as more appropriate for determining the size of contact area as it focuses on the geometry of tyre contact with the ground. [ABSTRACT FROM AUTHOR]

Railway bridges are subjected to significant dynamic loads. A numerical model of the bridge structure that captures its dynamic characteristics as accurately as possible is essential for the simulation of train crossings. However, most existing Calculation Models either do not consider the dynamic interaction between the structure and the soil, known as the soil–structure interaction (SSI), or give it only secondary importance. As a result, the accuracy of the predicted dynamic characteristics is affected. This paper illustrates how the dynamic interactions of abutments impact the portal frame bridge's SSI. This influence prompts the question of incorporating the frequency-dependent influence of the structure–soil–structure interaction (SSSI) into the modelling process. We propose a conservative estimation of the frequency range influenced by the shear wave interference of the SSSI and recommend using it as an application limit in the development of computational models. Based on this estimation, a Calculation Model is presented. In this approach, the SSI is considered using the well-known quasi-static spring–damper method from foundation vibration analysis, adhering to limitations based on the SSSI. For the application of the presented Calculation Model, four concrete portal frame bridges with spans between 9 m and 17 m along the high-speed line from Nuremberg to Munich, Germany, are investigated by analyzing the dynamic characteristics and comparing them with the prediction of the proposed numerical Calculation Model. The presented method shows good calculation accuracy. [ABSTRACT FROM AUTHOR]

In this paper, the shear behavior of concrete beams reinforced with FRP stirrups is studied. The shear performances of six concrete beams with a size of 150 mm × 300 mm × 3000 mm under four-point loading up to failure were experimentally analyzed. The critical parameters included the shear span to depth ratio (λ) and stirrup spacing (S). The test results revealed that as λ increased from 1 to 2, 3, and 4, the ultimate shear capacity of the beam decreases by 50.5%, 67.7%, and 69.2%, respectively. Meanwhile, as S increased from 100 mm to 150 mm and 200 mm, the ultimate shear capacity decreased by 16.1% and 44.6%, respectively. A new shear capacity calculation model of concrete beam reinforced with FRP stirrups was also proposed, which further considered the shear capacity of the FRP stirrups on the basis of the shear capacity of an RC beam without stirrups using the strut-and-tie model. Finally, the experiment and calculation results of 56 beam specimens reinforced with FRP stirrups extracted from this paper and previous studies were compared using the calculation models proposed in this paper, in order to evaluate the accuracy of these calculation models. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas & Oil is the property of Editorial Department of Natural Gas & Oil and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

High-strength reinforcement is an important direction in the development of civil engineering. In order to fill the gap that the current concrete structure code GB50010 has no standard regulations applicable to HRB600-grade high-strength reinforcement, this paper conducted an experimental investigation on the crack width of eight concrete beams reinforced with HRB600-grade high-strength reinforcement. The study examined various parameters to understand the crack development process, crack spacing, and factors influencing crack width in the pure bending section. The results revealed that the damage mode and crack development process of high-strength reinforced concrete beams were similar to those observed in ordinary reinforced concrete bending members. The crack spacing in the pure bending section was independent of the concrete strength, and the average crack width in the pure bending section exhibited a proportional relationship with the reinforcement strain. Moreover, both were mathematically related to the ratio of reinforcement diameter and ratio. A calculation formula for the maximum crack width suitable for HRB600-grade reinforced concrete beams was developed and fit. The HRB600-grade high-strength reinforcement had an obvious yield stage and good ductility, and the test study provides a powerful reference for promoting the application of high-strength reinforcement in concrete structures. [ABSTRACT FROM AUTHOR]

ObjectiveThis study aimed to establish an accurate and efficient scientific calculation model for the nutritional composition of catering food to estimate energy and nutrient content of catering food.MethodsWe constructed a scientific raw material classification database based on the Chinese food composition table by calculating the representative values of each food raw material type. Using China’s common cooking methods, we cooked 150 dishes including grains, meat, poultry, fish, eggs, and vegetables and established a database showing the raw and cooked ratios of various food materials by calculating the ratio of raw to cooked and the China Total Diet Research database. The effects of various cooking methods on the nutritional composition of catering food were analyzed to determine correction factors for such methods on the nutritional components. Finally, we linked the raw material classification, raw and cooked ratio, and nutritional component correction factor databases to establish a model for calculating the nutritional components of catering food. The model was verified with nine representative Chinese dishes.ResultsWe have completed the construction of an accurate and efficient scientific calculation model for the nutritional composition of catering food, which improves the accuracy of nutrition composition calculation.ConclusionThe model constructed in this study was scientific, accurate, and efficient, thereby promising in facilitating the accurate calculation and correct labeling of nutritional components in catering food.

In the course of towing of offshore platform, it is of great significance to calculate the towing resistance ahead of time and select the main tugboat with proper power for towing safety. In this paper, the calculation formulas or recommended methods for towing resistance of mainstream classification societies were investigated, and a CFD/AQWA finite element numerical simulation was conducted for the typical jack-up offshore platform in Shengli Petroleum Engineering Company.Based on the comparative analysis of the results, a suitable model for the calculation of towing resistance of platforms in domestic waters was optimized, and a suitable towing factor of safety was proposed.

Based on the structural and geological characteristics of the F1 weathering trough of a submarine tunnel and its spatial relationship with the cavern, a simplified calculation model of the weathering trough water inrush was established, and the formation, development process and influencing factors of the water inrush channel in the water-resistant rock layer were carried out by a numerical simulation of particle flow. It shows that the integrity and stability of the critical water-resistant rock mass is the key to preventing water inrush, and the identification and positioning of the water inrush channel is the basis for the grouting reinforcement design of the weathering groove of the submarine tunnel. Based on above research results, the F1 weathering trough was blocked and reinforced by the composite grouting method, and the engineering reinforcement effect was good.

To master the influence law of complex landform such as the surface mountain and the valley area between the mountains on the underlying coal rock stress, this study constructed a calculation model of the vertical stress of the coal strata under the mountain through theoretical analysis.Taking the 50205 working face of Hecaogou coal mine as example for analysis, This paper studied the complex landform on the underlying coal rock load characteristics and stress transfer law.Results show that: mountain load has significant stress effect on shallow coal seam.In the horizontal direction, the influence range is negatively correlated with the mountain slope, and the coefficient of influence range is positively related to the mountain slope.The effect of mountain on the vertical stress of the underlying coal seam can be divided into three stages: initial effect, intense growth effect and slow growth effect.The vertical stress superposition value of the underlying coal strata in the gully region firstly increases and then decreases with the change of depth.Moreover, when the distance between two adjacent mountains increases to more than.1.25 times of the width of the mountain bottom, the effect of stress superposition is very small and can be ignored.As the distance between adjacent mountains gradually increases, an inverted triangle area with insignificant stress superposition is formed in the coal strata under the gully area.

Copyright of Petroleum Geology & Oilfield Development in Daqing is the property of Editorial Department of Petroleum Geology & Oilfield Development in Daqing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Determination of health service tariffs also determines optimal health service outcomes. Determination of radiology examination rates at Naibonat Hospital until 2023 still refers to Regional Regulation No. 5 of 2012 concerning public service fees, where the determination of fees still uses the conventional calculation system, and there are changes in image processing modalities, tools, and materials used, this demands a rate adjustment. Calculation of rates using the Activity Based Costing (ABC) method, can be a solution to determine more accurate rates, supported by Pramawati's research (2021) which shows the results of determining rates are more accurate using the ABC method. The purpose of this study was to calculate the tariff pattern for radiological examinations at Naibonat Hospital using the ABC method and obtain an accurate tariff calculation model for radiological examinations. This research is a descriptive explorative study, with a quantitative approach using numerical data which aims to calculate a unit cost-based examination rate model by implementing an Activity Based Costing system on ultrasound examination of the abdomen, chest x-rays, abdomen, skull, and extremities. The data obtained was then subjected to qualitative analysis to obtain the steps for calculating tariffs using the ABC method. The results of this study indicate that the calculation model for radiological examination rates using the ABC method is valid. To find rates, first, determine the basic rate with the formula unit cost = direct cost + overhead, the results obtained are then calculated. Examination rates = cos unit + hospital services, so the examination rates at the Radiology unit of Naibonat Hospital, namely abdominal USG Rp 242.036, photo thorax Rp. 116,995, photo abdomen Rp. 150,321, photoskull Rp. 153,262, and a photo extremity Rp. 121,409. [ABSTRACT FROM AUTHOR]

A pressure filtration–flocculation–solidification combined treatment possesses great potential for the reutilization of the waste mud slurry generated from diverse construction projects as filling material due to its versatility and high efficiency. However, very limited existing studies have focused on the factors affecting pressure filtration's efficiency. In this paper, a calculation model for compression filtration is established based on laboratory pressure filtration model tests and one-dimensional large-strain consolidation theory. The influence of various parameters on pressure filtration's efficiency is analyzed, and favorable values for these parameters are recommended. The results show that an increased initial mud cake thickness significantly increases the dewatering time and reduces the treatment's efficiency. A lower dewatering time and higher efficiency can be achieved by increasing the filtration pressure, but the efficiency improvements become limited after reaching the critical pressure threshold. For the mud slurry used in this study, the optimal values for the initial mud slurry bag thickness, filtration pressure, and dewatering time are 240 mm, 1.0 MPa, and 30 min, respectively, yielding a final mud cake water content of 58.7% after filtration. [ABSTRACT FROM AUTHOR]

Since reinforced concrete members suffer from different types of loads during their service life, the steel bars embedded in reinforced concrete members can be easily corroded in chloride‐laden environment. To investigate the influence of combined effect of load and steel corrosion on the flexural stiffness of recycled aggregate concrete (RAC) beams, 12 RAC beams were prepared and tested. The effects of load level (i.e., the ratio of the load applied to beams to the ultimate load) and recycled coarse aggregate (RCA) replacement ratio (i.e., the ratio of RCAs to replace natural coarse aggregates) on the internal force arm coefficient of cracking cross‐section, the elastoplastic resistance moment coefficient of cross‐section, and the strain incongruity coefficient of corroded tensile steel bars were analyzed, and a calculation model for flexural stiffness of RAC beams under combined effect of load and steel corrosion was established. The results showed that when the ratio of bending moment to ultimate bending moment of the pure bending part of beams was within 0.55–0.80 and the average mass loss of tensile steel bars was less than 3.23%, 0.85 could be adopted as the internal force arm coefficient of cracking cross‐section. The elastoplastic resistance moment coefficient of cross‐section was approximately a constant when the corroded RAC beams were in the service stage, while it increased obviously with the load level. There was a strong linear relationship between strain incongruity coefficient and average mass loss of tensile steel bars during the service stage of corroded RAC beams, and the strain incongruity coefficient increased linearly with the load level. The calculated values of the model of flexural stiffness proposed in this paper were in reasonable agreement with the experimental values. [ABSTRACT FROM AUTHOR]

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