To obtain a comprehensive overview of the latest advances and trends in ecological concrete research in the field of the sponge city construction industry, the search steps were as follows: the search time was set from 1999-12-31 to 2021-12-31, with “ecological concrete” as the topic and TS (subject) = (“Ecological concrete OR Eco-concrete OR Green concrete OR pervious concrete OR Environmental friendly concrete OR Sustainable concrete”) as search criteria for advanced search, a total of 25353 documents were obtained, the research direction was selected as Construction Building Technology, and the article type was set as Article or Review, a total of 5300 articles were accepted.

Currently, commonly used knowledge graph analysis software including VOSviewer, CiteSpace, etc. Are used to clearly and accurately analyze development trends, research fronts, research hotspots, and other related issues in a particular knowledge domain. CiteSpace uses the hot word analysis function to draw the knowledge map in the scientific area, and intuitively displays the research hotspots and development trends in a particular stage (Chen and Chen, 2005; Zhao et al., 2012; Chen et al., 2015; Li and Chen, 2016; Chen, 2017). VOSviewer is a software developed by Van Eck and Waltman at Leiden University in the Netherlands for constructing and visualizing econometric networks. It can build networks for journals, researchers, keywords, and publications based on co-citation, coupling, and co-authorship relationships (Waltman et al., 2010). This paper uses VOSviewer and CiteSpace software to analyze the number of published articles, publishing institutions, literature sources, core author groups, research hotspots, and future trends. Table 1 is the inclusion and exclusion criteria for the selected literature.

In this paper, we analyze the number of papers published in the field of ecological concrete construction and the major source journals.

Analyzing the relationship between the number of papers published and the research results in the field of ecological concrete can provide research direction in this field and reflect the theoretical basis and practical value of cooperation in the research field to a certain extent, which can better highlight the Frontiers of research in the area (Xie et al., 2020). Interaction among scientists has long been the essence of scientific practice (Melin and Persson, 1996). Most stages of the research process involve a great deal of communication: scientists talk to each other; In short, they communicate and collaborate.

Models of Sino-foreign cooperation have emerged in a number of fields, including education and tourism. Similarly, in ecological city construction, Sino-foreign cooperation has been successful. De et al. (2013) identified the conditions for Sino-foreign cooperation in ecological cities, studied the organization of Sino-foreign cooperation, and constructed a typology of Sino-foreign cooperation in ecological knowledge cities. Their development has a critical impact on improving a region’s competitiveness in globalization (Ovalle et al., 2004; OECD, 2005). It requires robust organizational capacity to build such a foundation with broad participation from public and private players, academia and the wider community.The influx of high-tech knowledge usually comes from abroad, and promoting science and technology is also a key factor in the success of eco-towns.Hence, success is most likely to be achieved through collaboration within a solid consultation framework and exchange between individual scientists and institutions.

Collaborative analysis can be done specifically in terms of regions, institutions, and authors. When ecological concrete forms a systematic study in the construction industry, it facilitates the development of ecological concrete and forms a unique model and framework for ecological concrete research.

To further explore the analysis of research hotspots in ecological concrete construction, this paper analyzes keyword clusters as well as keywords through Figure 6 and Table 8. The 14 groups are divided into two parts.

The first category of hot topics includes clusters such as #1 life cycle assessment, #12 sustainable design model, and #14 multi-scale computational model, which can be summarized as some methods, performance models, and evaluation systems based on the research of ecological concrete. “Construction”, “Design”, “Model”, “Pore structure ", “Pore structure”, and “Life cycle assessment” are the keywords of this section.

In China, based on research on recycled concrete technology, life-cycle assessment has been used to establish a whole-life-cycle environmental and economic performance assessment system for recycled concrete, analyzing, adjusting and setting key processes (Tian, 2012). A sustainable design model is a design that can be used on material structures to optimize the mix of building materials and reduce CO2 emissions. Choi et al. (2016) eveloped a sustainable design model for SRC composite structures, which was used to comprehensively analyze changes in CO2 emissions during construction of the building. Multiscale computational models are a method for multiscale modeling of interfacial connections in concrete structures. Gong et al., 2018 proposed a multi-scale simulation of visible mechanical damage to concrete caused by mixed microporous pressure. The combination of new models provides many new ideas for the study of ecological concrete (James et al., 2009; Jahn et al., 2012; Abson et al., 2017), and the integration of different models, disciplines, and fields is instructive for the development of ecological concrete in the construction field. Models can predict performance, and accurate models can reduce the number of experiments, shorten the experimental cycle, save time, cost, and materials, contribute to environmental protection, and enable new research topics and hot issues in the field to emerge and develop towards industrialization.

The second category of themes can be summarized as specific directions for the development of ecological concrete with the clusters #2 ultra- High-performance concrete、#3 recycled concrete aggregate、 #4 pervious concrete、#5 thermal properties、#6 3 days printing、#7 foamed concrete、#8 Glass cullet、#9 sodium chloride、#10 bfrp bar (Basalt fiber reinforced polymer (BFRP) bars)、#11 steel corrosion、#13 plastic waste these.

Due to the construction and development of railroads, highways, mines, and water conservancy projects (Andrew, 1990; Bennett, 1991; Cohen-Fernández and Naeth, 2013; Shao at el., 2014), a large number of exposed rock slopes and fragile banks slopes have been formed (Bengtsson at el., 2000; Zeng et al., 2020; Walia et al., 2017; Zeng et al., 2019). Affected by natural climates such as rainfall, weathering, and dry-wet cycles, the slopes are prone to runoff, resulting in a large amount of soil erosion (Caro et al., 2014; Handa et al., 2019). In this case, ecological concrete can meet the primary responsibilities of concrete and ecological conservation of biodiversity. Compressive strength, porosity, PH value, and vegetation properties affect its mechanical properties because when porosity is too high, good permeability promotes the decomposition of hydrates and reduces strength, while admixtures will inevitably affect durability (Wu et al., 2005; Wang et al., 2022). With the increasing demand for environmental protection and conservation, ecological concrete has attracted more and more attention (Zhang and Wen, 2008; Xiang et al., 2020). Previously, ecological concrete was mostly used in slope protection where the alkaline environment restricted the growth of plants (Shi et al., 2011; Wang et al., 2019; Wasim et al., 2022), so fly ash, silica fume, and rice hull ash are applied in vegetation concrete to replace cement and Portland cement to reduce the alkalinity of the internal environment while maintaining strength.

An essential technological breakthrough in ecological concrete is the reuse of waste concrete (Yu and Yu, 2009), and recycled concrete is a joint research topic in developed countries. So far, this has been done using recycled aggregates and waste materials such as corn cobs, shells, glass fragments, fabric and plastic waste, rather than ordinary aggregates made from recycled concrete. Pervious concrete has been increasingly used to reduce water runoff and improve water quality near sidewalks and parking lots, with high performance requirements, often with external admixtures such as silica fumigants and high-efficiency water dewatering agents to improve its performance. Foam concrete has high strength-to-weight ratio and low density, among other things. Its use reduces static loads on structures and foundations, which is beneficial for energy savings and reduces labor costs during construction. Amran et al., 2015 examines the composition, fabrication techniques and properties of foam concrete, providing a comprehensive insight into possible applications of foam concrete in today’s construction industry.

Due to the rapid development of ecological concrete, it has become a trend to combine technical and common concrete. 3D printed concrete combines 3D printing and concrete, and there are still many challenges in the level of technology and processing. 3D printed concrete is a new type of digitally manufactured concrete, with the addition of technology to increase shape complexity and reduce the use of materials in concrete, which is more environmentally friendly but lacks rheological and hardening properties. Numerical simulation and machine learning, an emerging method combined with ecological concrete construction, is an inevitable trend in concrete development (Jiang et al., 2018; Chang et al., 2020; Huang et al., 2020).

To promote the mass use of ecological concrete for the sustainable development of the world (Kim and Park., 2016; Gao et al., 2020; Faiz et al., 2022; Kong et al., 2022), researchers need to continue their efforts to realize the industrial production of ecological concrete table 8.

Emergent words, which can provide researchers with the latest evolution and direction of the discipline, refer to a sudden increase in the citation frequency of a particular document within a certain period. A larger number of citations indicates that many related studies have appeared. Thus, the recent emergent nature represents a research Frontier. Using the mutation detection algorithm of CiteSpace V, information on emergent words is obtained, as shown in Figure 7. After analysis, this period can be divided into three points in time. By tracing these emergent words, we can find that they are closely related to ecology and that the protection of the global environment and sustainable development have been the primary goals in the world since the last century, even now and in the future (Jacobs, 1999).

Since 2000, concrete has been required not only to meet the requirements of being a structural material, but also to minimize load and negative impact on the global environment and contribute to global sustainability. Gupta et al., 2021 is focused on developing green self-compacting concrete using industrial by-products such as foundry waste sand, coal bed ash, waste tire rubber, copper slag and waste glass as acceptable aggregates substitutes.These industrial by-products have great potential for use in self-compacting concrete, leading to sustainable development. The reuse of waste concrete (Yu and Yu, 2009) is an essential technological breakthrough in the field of ecological concrete. There are many studies on the effect of waste concrete as recycled aggregate on the performance of recycled concrete (Chen et al., 2013; Zhang et al., 2018). Zou and Cao (2020) used waste concrete with different strengths to make regenerate aggregates and study their properties. In addition, attention has been paid to the resource utilization of industrial waste through innovative disposal methods, one of which is its use as a filling material or volcanic ash for concrete production. Ji et al. (2021) and Liu et al. (2021) prepared corn cob aggregate ecological concrete by mixing broken corn cob particles into recycled mortar. Xie et al. (2021) and Liu et al. (2020) prepared ecological concrete using volcanic stone as coarse aggregate with different porosity. Murugan et al. (2020) used shells as a substitute for granite aggregate. Olofinnade et al. (2018) used waste glass in concrete to achieve sustainable benefits of reducing solid waste and greenhouse gas emissions. Javali et al. (2017) proposed using aluminum slag and granular iron slag as partial replacement materials for cement and natural sand, respectively, to develop ecological concrete. The research on recycled aggregates has important implications for energy saving and emission reduction, as well as a new innovative direction for ecological concrete.

Since 2011, the concept of “life cycle” has been emerging. The basic idea of a life-cycle assessment is that all environmental burdens associated with a product or service must be assessed, from the raw material all the way through to waste disposal. When the need for raw concrete materials shifted to the study of recycled materials, it entered the “life cycle” category. The Life Cycle Assessment (LCA) is the only environmental assessment tool that avoids a positive rating that only includes the measurement of the transfer burden. Life-cycle assessment can provide recommendations for the optimal design of ecological concrete processes, suggesting strategies and policies for industrialization of recycled concrete that are consistent with national conditions, taking into account the issues that need to be addressed in the promotion of ecological concrete. After 2016, it can be concluded from the emergent words such as lightweight aggregate concrete, high strength, and permeable pavement that the development of ecological concrete tends to mature with the improvement of the economy and technology, and there are higher requirements for other properties other than the basic performance, such as light aggregate concrete and high strength permeable pavement. Lightweight aggregate concrete is characterized by its light weight, high strength, thermal insulation, fire resistance and good seismic performance, as well as its good deformability, low modulus elasticity and low shrinkage creep. It can be used in industrial and civil construction, among other projects, and has the advantage of reducing the weight of structures and saving material consumption. Permeable pavement makes porous concrete in cold climates to solve freeze-thaw and crack resistance problems. It can be seen that the development of ecological concrete in the construction sector is getting better, and the transition from ordinary ecological concrete to high-performance ecological concrete is just around the corner.