Journal of building engineering最新文献

{"title":"A dual-adaptive directed genetic algorithm for construction scheduling","authors":"Zhaozheng Shen, Jie Wu, Yilun Cao","doi":"10.1016/j.jobe.2024.110659","DOIUrl":"https://doi.org/10.1016/j.jobe.2024.110659","url":null,"abstract":"The precise and efficient generation of construction sequences is a crucial concern within the engineering field. However, the formulation of construction schedules heavily depends on the expertise and proficiency of project planners, leading to significant potential for inefficiencies and instability in project management. To deal with this challenge, this study automatically extracts constructability constraints from 3D models and proposes a dual-adaptive directed genetic algorithm (DADGA) to generate a structurally stable installation sequence. The proposed algorithm adaptively changes both the crossover and mutation probabilities based on the quality of individuals and evolutionary stages. In addition, the idea of directionality and the chief strategy artificially controls the direction of evolution, which greatly improves the efficiency and robustness of local search. The results of comparison experiments demonstrate that the DADGA outperforms the traditional genetic algorithm in terms of both efficiency and accuracy, and a practical example is also presented to showcase the capability of the DADGA in solving ultra-complicated construction scheduling problems.","PeriodicalId":15064,"journal":{"name":"Journal of building engineering","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142144071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intelligent mix design of steel fiber reinforced concrete using a particle swarm algorithm based on a multi-objective optimization model","authors":"Benbo Sun, Pengfei Wang, Jinjun Guo, Yuanxun Zheng, Peng Zhang, Juan Wang, Jianjun Tan","doi":"10.1016/j.jobe.2024.110653","DOIUrl":"https://doi.org/10.1016/j.jobe.2024.110653","url":null,"abstract":"Steel fiber reinforced concrete (SFRC) is widely used in construction and is important for concrete-based applications. Nevertheless, compared with conventional concrete, it is difficult to efficiently and accurately design SFRC with a given mix ratio, because many factors affect the SFRC performance. This study proposes a multi-objective optimization model using numerical simulations and artificial intelligence to effectively derive the optimal SFRC mix proportion. For a quick and accurate relationship between the SFRC mix ratio and compressive strength, Latin hypercube sampling was used for sampling the random variables determining the mix ratio, yielding a set of random numbers. Subsequently, a finite-element simulation dataset was constructed, and a backpropagation neural network (BPNN) was used for predicting the complex nonlinear relationship between the raw material mix proportions and uniaxial compressive strength (UCS). The BPNN model was then utilized as the objective function in the multi-objective particle swarm optimization model, with the mix ratio parameters as the input variables and the compressive strength, unit production cost, and carbon dioxide emission as objective functions, which facilitated the search for the optimal mix proportion, yielding a Pareto-optimal solution set. Finally, based on the engineering preferences, the best solution was determined to be the recommended mix proportion.","PeriodicalId":15064,"journal":{"name":"Journal of building engineering","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142144074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficient analysis and evaluation method for overall lifting of large-span spatial grid structures","authors":"Xiaonong Guo, Zhengang Sui, Zhengning Li, Jindong Zhang, Yujian Zhang, Shaohan Zong","doi":"10.1016/j.jobe.2024.110657","DOIUrl":"https://doi.org/10.1016/j.jobe.2024.110657","url":null,"abstract":"Large-span spatial grid structures are commonly employed on the roofs of various public buildings and are typically installed via an overall lifting method. However, the process of overall lifting cannot ensure complete synchronization, which may result in damage to the structure or the lifting equipment. It is imperative to ascertain the limit state of the structure under asynchronous conditions and to develop an accurate model for rapidly assessing the critical response during the lifting process. This paper introduces an efficient approach for evaluating and analyzing the overall lifting process of large-span spatial grid structures. The iterative limit boundary (ILB) method is proposed in this paper, which facilitates the rapid determination of the limit boundary and the limit state for a structure-equipment system with asynchronous lifting. Furthermore, the genetic algorithm is integrated into the ILB method to enhance its efficiency when dealing with numerous lifting points. An agent model capable of outputting key structural responses is developed for the rapid evaluation of those responses throughout the lifting process. Both a numerical example and an engineering example are provided to validate the proposed method. The computational results indicate that the method proposed achieves accurate results with a computational cost merely 3 % of that of the Monte Carlo simulation. Additionally, the agent model established within the limit boundary, operates at a speed 200 times faster than finite element analysis, thereby enabling precise and real-time critical response assessments.","PeriodicalId":15064,"journal":{"name":"Journal of building engineering","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142144077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synergistic performance of microwave-activated coal gangue with limestone in low-carbon cement","authors":"Ling Wang, Shiyong Mi, Junfei Zhang, Hao Zhou","doi":"10.1016/j.jobe.2024.110622","DOIUrl":"https://doi.org/10.1016/j.jobe.2024.110622","url":null,"abstract":"This study aims to apply microwave-activated coal gangue (MCG) to develop limestone calcined clay cement (LC). The impact of microwave activation schemes (microwave temperature and holding time) on the pozzolanic activity of coal gangue were explored. After that, LC cements were prepared by replacing cement clinker with limestone powder (LS) and MCG at different ratios. The uniaxial compressive strength, phase composition, microstructure, and pore structure of the MCG-based LC cements were analyzed. The results indicate that the maximum volcanic ash activity index is achieved when the material is microwave-activated at 800 °C with a holding time of 20 min. The MCG based LC cements achieve the highest strength at an MCG content of 20 % with an MCG:LS ratio of 2. Then, the response surface methodology was employed to predict the optimal mixture proportions for achieving the best strength of the material. The life cycle analysis shows that the carbon emission of the MCG-based LC material is 30 % lower than that of Ordinary Portland Cement. This study develops a new high-performance material with low carbon emission for construction industry.","PeriodicalId":15064,"journal":{"name":"Journal of building engineering","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142144078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Compressive mechanical performance and microscopic mechanism of basalt fiber-reinforced recycled aggregate concrete after elevated temperature exposure","authors":"Xianggang Zhang, Yanan Zhu, Youchuan Shen, Junbo Wang, Yuhui Fan, Xiang Gao, Yajun Huang","doi":"10.1016/j.jobe.2024.110647","DOIUrl":"https://doi.org/10.1016/j.jobe.2024.110647","url":null,"abstract":"To improve the mechanical properties of recycled aggregate concrete (RAC) after elevated temperature exposure, this study employed basalt fiber (BF) as reinforcing material incorporated into RAC. The replacement ratio of recycled coarse aggregate (RCA), the content of BF, and the temperature were utilized as the change parameters, and 27 groups of basalt fiber reinforced recycled aggregate concrete (BFRRC) specimens were designed to carry out the compressive strength test after elevated temperature. The heating rate was set at 2.5 °C/min to avoid any possible explosion of the cylindrical specimen during the heating process. The specimens were treated for 6h after reaching the desired temperature, and then the furnace door was opened for natural cooling to room temperature. After observing the physical properties of the specimens, the basic mechanical properties test was carried out, and the microscopic mechanism was analyzed in depth by electron microscopy. The results showed that the defects inherent in RCA and the continuous accumulation of elevated temperature damage gradually reduced the compressive mechanical performance of BFRRC but that the toughening and cracking-resistance action of BF effectively improved the compressive mechanical performance of BFRRC. BF enhanced the compressive mechanical performance of RAC through bridging and crack resistance action mechanisms, but the higher the temperature became, the smaller the enhancement was. The cube compressive strength and axial compressive strength of the specimens decreased with the increase of temperature. With the same replacement ratio and fiber dosage, increasing the temperature from 300 °C to 600 °C, the decrease in cube compressive strength and axial compressive strength was the most significant, which was between 36.4 %–48.1 % and 51.1 %–62.6 %, respectively.","PeriodicalId":15064,"journal":{"name":"Journal of building engineering","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142144072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructure and residual strength properties of engineered geopolymer composites (EGC) subjected to high temperatures","authors":"Saravanan Subramanian, Robin Davis, Blessen Skariah Thomas","doi":"10.1016/j.jobe.2024.110637","DOIUrl":"https://doi.org/10.1016/j.jobe.2024.110637","url":null,"abstract":"This study investigates the effects of high temperature on the microstructure and residual compressive strength properties of engineered geopolymer composites (EGC). The importance of this study focusses on the performance and durability of EGC, aiming towards sustainable construction practices. The proposed study fills the knowledge gap by the use of steel fibers (SF) as primary reinforcement in EGC, specifically involving a combination of Fly Ash (FA), Basic Oxygen Furnace (BOF) slag, and Iron Ore Tailings (IOT). The residual properties of EGC under high-temperature conditions were assessed by preparing cube specimens (50 mm) involving FA and BOF slag as primary precursors, with IOT as a partial replacement to conventional fine aggregate (M-sand) and brass-coated SF as discrete reinforcement. The specimens were exposed to temperatures up to 1000 °C in a muffle furnace in six different levels: 25, 200, 400, 600, 800, and 1000 °C. Post-exposure, the specimens were ambient cured prior to testing of pore structure distribution, residual strength properties, and microstructural characteristics involving scanning electron microscopy (SEM) analysis. The experimental findings show that, despite various combinations of precursors, IOT and SF, no explosive deterioration or spalling occurred in EGC mixes at any level of exposure. Also, as the exposure temperature increased, the compressive strength decreased while the strain capacity enhanced, denoting an increase in the stiffness of the EGC mixes. Notably, the SF maintained its structural integrity even at 1000 °C, which was consistent with the observed microstructural behavior. This indicates the proposed EGC exhibits excellent resistance to elevated temperatures and enhanced strain-hardening capacity. Overall, this research provides valuable insights into the residual properties and microstructural characteristics of FA: BOF: IOT-based EGC, highlighting its potential as a sustainable and fire-resistant building material. The outcomes contribute significantly to the existing knowledge on EGC and its application in environments exposed to high temperatures.","PeriodicalId":15064,"journal":{"name":"Journal of building engineering","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142144073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of metallurgical ferronickel slag in building materials: A review","authors":"Song Yanning, Hongxia Qiao, Feng Qiong, Wei Chao, Zheng Jianghua","doi":"10.1016/j.jobe.2024.110632","DOIUrl":"https://doi.org/10.1016/j.jobe.2024.110632","url":null,"abstract":"Ferronickel slag (FNS) is an industrial solid waste discharged during the production of ferronickel alloy. The annual discharge and total stockpile of FNS keep rising due to the increasing global demand for nickel resources, but its comprehensive utilization rate remains low. Using FNS as supplementary cementitious material (SCM) or fine aggregate can improve the comprehensive utilization rate of FNS and reduce the impact of building materials on the ecological environment, which conforms to the concept of green, environmental protection and sustainable development. This paper reviews the research results of FNS applied in building materials, especially the related research of FNS as SCM, fine aggregate and geopolymer. The results show that when FNS is used as SCM, its active component is less, the degree of hydration reaction is lower, and the substitution rate is not easy to exceed 20 %. However, mechanical ball milling can significantly enhance the filling effect of FNS and increase its amorphous phase content, thereby improving the performance of FNS. In addition, with the introduction of alkali activator, the reactivity of the cementitious system can be further stimulated. The active excitation method increases the substitution rate of FNS to 30 %, which broadens its application range and efficiency. When FNS is used as fine aggregate, when the replacement rate is set at 40%–50 %, the working performance, mechanical properties and durability are the best. Nevertheless, how to solve the potential alkali-silica reaction of FNS fine aggregate is the focus of future research. In addition, the establishment and performance research of FNS geopolymer composite system still need to be further explored. Finally, combined with the research results of this paper, the future research prospects are put forward.","PeriodicalId":15064,"journal":{"name":"Journal of building engineering","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142144106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of bending and shear properties of mixed softwood & hardwood cross-laminated timbers","authors":"Esra Satir, Sailesh Adhikari, Daniel P. Hindman","doi":"10.1016/j.jobe.2024.110646","DOIUrl":"https://doi.org/10.1016/j.jobe.2024.110646","url":null,"abstract":"The current version of PRG-320 (CLT) that governs CLT manufacturing and design, limits production to softwood species. As a result, the growing demand for CLT production could strain the supply of softwood lumber in the US within the next decade. The inclusion of hardwood in CLT production alongside softwood could be a potential solution to this problem. This paper investigates the bending and shear test results of three- and five-layer mixed species CLT beams manufactured using various combinations of yellow-poplar and southern pine. The beams were evaluated for bending strength, bending stiffness, shear strength, and shear stiffness, as well as quality control testing of moisture content, specific gravity, resistance to shear by compression loading and resistance to delamination. The experimental values for all CLT groups, adjusted according to the Allowable Stress Design (ASD) to ensure stress limits are not exceeded, were greater than those calculated using the shear analogy method. The only exceptions were bending stiffness values for the groups with all layers of southern pine and those with outer layers of southern pine and inner layers of yellow-poplar (see Table 1 for layups codes), where the differences remained within a minor range of 4 %. Although, wood failure percentages in resistance to shear by compression loading fell below the maximum value of 80 %, and face delamination percentages in resistance to delamination were above the minimum value of 5 % according to the corresponding standards. The mechanical properties of all CLT beams met or exceeded shear analogy values. The test results indicated that yellow-poplar could be a viable alternative to southern pine in the production of CLT due to its similar specific gravity. This suggests that mixed-species CLT can maintain or enhance structural performance while addressing material shortages. Furthermore, the use of yellow-poplar in CLT production promotes sustainable forestry practices, supports resource diversification, and encourages innovation in construction methods. These findings have significant practical implications for the timber and construction industries, contributing to cost efficiency and environmental sustainability.","PeriodicalId":15064,"journal":{"name":"Journal of building engineering","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142144105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Overcoming the brittleness of sustainable compression-cast recycled aggregate concrete through steel spiral confinement","authors":"Fang Yuan, Mingkang Wang, Yufei Wu, Jinlong Pan","doi":"10.1016/j.jobe.2024.110634","DOIUrl":"https://doi.org/10.1016/j.jobe.2024.110634","url":null,"abstract":"The loose and porous adhered mortar of recycled aggregates produces concrete with low strength and poor durability. The newly developed compression casting technology applies pressure to fresh concrete to squeeze out excess water and air in the recycled aggregate concrete (RAC) and force the cement paste into the old adhered mortar to strengthen it, thereby effectively solving the aforementioned problems. However, the significant increase in the compactness and compressive strength of the RAC is accompanied by a pronounced increase in compression brittleness. Hence, this study attempts to overcome the brittleness of sustainable compression-cast RAC through proper design of transverse reinforcement. To achieve this objective, the axial compression behaviour of steel spiral-confined RAC specimens was experimentally investigated. It is found that the compression casting approach almost doubled the compressive strength of the unconfined RAC and improved the ultimate axial stress of the steel spiral-confined RAC by up to 69.9 %. The steel spiral-confined normal-cast RAC exhibited typical compression failure accompanied by a stress–strain curve characterised by strain hardening, whereas the steel spiral-confined compression-cast RAC exhibited localised shear failure accompanied by a stress–strain curve characterised by strain softening. The strain-softening behaviour of steel spiral-confined compression-cast RAC can be significantly improved by reducing the spiral pitch. Based on the test results obtained in this study and in the literature, stress–strain models were proposed separately for the steel spiral-confined compression-cast RAC and normal-cast RAC. The stress–strain models exhibited a significantly higher prediction accuracy than the selected models in the literature.","PeriodicalId":15064,"journal":{"name":"Journal of building engineering","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142144076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical characteristics and constitutive model of cemented tailings backfill under temperature-time effects","authors":"Chao Zhang, Jinping Guo, Abbas Taheri, Weidong Song, Xiaolin Wang, Wenhao Xia","doi":"10.1016/j.jobe.2024.110630","DOIUrl":"https://doi.org/10.1016/j.jobe.2024.110630","url":null,"abstract":"The increase in original rock temperature during the deep metal mine backfill mining process significantly impacts the mechanical properties of cemented tailings backfill (CTB). Uniaxial compression experiments were conducted under various curing temperatures and times, analyzing their mechanical characteristics based on strain energy. The experimental results indicate that the mechanical properties of CTB are significantly affected by temperature. The uniaxial compressive strength (UCS) follows a quadratic trend, initially increasing and then decreasing as the curing temperature changes. At the curing temperature of 40 °C, the hydration reaction of CTB develops fully, the hydration products have strong compactness, and the energy absorbed when failure occurs is the largest. The CTB is divided into a solid framework and pore sections to develop a constitutive damage model using a combined macro and micro experimental approach. Polynomial functions represent the correlation between the damage model parameters and curing time and temperature, resulting in a unified temperature-time damage constitutive model. Using the secondary development platform in FLAC finite difference software, the damage constitutive model of the CTB was further developed and integrated into the software, enabling both its development and application. This customized model provides a more comprehensive representation of the overall deformation and failure mechanisms of the CTB during compression. The study can predict the strength of CTB under different curing conditions, and provide theoretical reference for the simulation research of filling mining in mines.","PeriodicalId":15064,"journal":{"name":"Journal of building engineering","volume":null,"pages":null},"PeriodicalIF":6.4,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142144138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}