Large-scale Infrastructure Construction Research Articles

The promise and reality of middle-class homeownership in China: housing assetisation, speculative urban (re)development and residential inequalities

ABSTRACT This paper offers a nuanced understanding of China’s housing assetisation by (1) examining its role in supporting financialised urban (re)development after the global financial crisis, and (2) dissecting the contradictions between seemingly flourishing housing markets and deep-seated residential inequalities. Drawing on the case of Guangzhou, this paper first illustrates how housing assetisation internalizes financial norms within Chinese homeowner society, signifying a shift in the mode of social regulation from managerialism to entrepreneurialism. This shift is evident in the capitalization of priority access to public infrastructure and the prevailing culture of accumulation, investment and speculation. In the post-crisis era, housing has been repackaged as a lucrative investment by the local state through dazzling (sub)urban projects, large-scale infrastructure construction and ambitious urban-planning proposals, thereby fueling a home-buying frenzy. We argue that the assetisation-induced social ethos of capital accumulation and speculative investment, entwined with infrastructure-cum-property-led urban (re)development, has recast Chinese cities into shareholder-value machinery. As the local state leverages household savings and income streams to bolster land-based financialised urban development, homeowners/buyers are transformed into investor-citizens. This transformation implies that urban household balance sheets become intricately linked with China’s urban fortunes. Moreover, residential inequalities are exacerbated, exemplified by prevalent gentrification “at a premium”.

Evaluation of geosynthetic encased columns in Zambian heterogenous soils

The development of Zambia has brought increased large-scale infrastructure construction that has necessitated the need for improved foundation techniques that are both economical and adequate in capacity. Clay and soft soils with low bearing capacities and high compressibility could render structural foundations to perform poorly and shorten the design life of the bridges and structures. This study used a bridge case study in Northern Province, Zambia to investigate the use of geosynthetic encased columns (GECs) to support the bridge embankments to reduce differential settlements. End bearing fully encased columns were compared to floating columns of varying lengths by numerical modelling in PLAXIS 3D. The Hardening Soil and Mohr–Coulomb soil models were used for the column surrounding soil and the GECs in the finite element analysis. The results showed that the end bearing columns had the least differential settlements at the soil surface, whilst the reduction in floating column length increased the punching settlements. Moreover, the shear stress along the interface of the GECs and surrounding soil varied from 20 kN/m2 to 142 kN/m2, where the end bearing GEC had the least shear stress.

Factors in Community Adaptation for Climate Change Mitigation in Thailand

This study reflects the experiences of communities who have adapted to climate change in three different geological locations in the country of Thailand: by the riverside, coast, and in the mountains. The communities presented the lessons learned and identified key adaptation factors. The study used in-depth interviews and focus group discussions, with results showing that the community’s learning and adaptation to climate change were at a high level. The results broaden understanding of climate change in these locations and provide information for resource management approaches. Among the seven factors, five factors illustrated that they were highly adapted, including: (1) applying knowledge about nature, ecosystems, and traditional wisdom; (2) management that allowed the use of adaptations; (3) a shared vision of success; (4) collaboration; and (5) having a variety of options and approaches. Two factors that illustated that the community was only moderately adapted included: (1) learning about violent events and disasters; and (2) following government guidelines. It was found that a lack of information about the ecosystems and environmental resources they required for large-scale infrastructure construction caused issues. This is a problem, and the government must consult with local communities when setting long-term plans and assessing needs, because communities have diverse livelihoods and depend on natural resources. Hence, future studies should include climate change awareness and understanding of what is required by adding community needs linked to climate change adaptation into state development plans as well as utilizing the wisdom and traditional knowledge involving ecology held by these communities into sustainability plans.

Sustainability evaluation of urban large-scale infrastructure construction based on dynamic fuzzy cognitive map

Enhancing the sustainability of large-scale infrastructure construction is the foundation and trend of urban sustainable development and environmental protection. This paper proposes a perception and evaluation method based on Dynamic Fuzzy Cognitive Mapping (D-FCM) to address the dynamics, uncertainties, and implementation difficulties of sustainability evaluation in large-scale infrastructure construction. Using Hebbian rules to learn the experience and knowledge of experts, a dynamic evolution correlation matrix about evaluation indicators is obtained, and a D-FCM dynamic system model is established to obtain the sustainability evaluation results of large-scale infrastructure construction. The comprehensive sustainable evaluation value (K) of the selected subway project case is 0.934, which belongs to the V level in the sustainable level classification standard and has a good trend in sustainable development. Social public participation (S1), light pollution prevention (H1), wastewater discharge compliance rate (H2), soil pollution prevention (H3), and soil and water conservation and utilization (Z2) are the most significant and sensitive indicators for the sustainable development of large-scale infrastructure construction. Based on the interaction of influencing factors in the D-FCM model, an economically efficient control measures and decision-making plan can be proposed to improve the sustainability of large-scale infrastructure construction projects.

China–Pakistan Economic Corridor

China and Pakistan celebrated the 10th anniversary of the launch of the China–Pakistan Economic Corridor (CPEC) in 2023. Over the past decade, the CPEC has been developed amid controversies and challenges, and has achieved notable successes, especially in large-scale infrastructure construction, which has laid the foundation for Pakistan’s economic development in the long term. However, the ever-changing domestic and international environment has not alleviated the challenges and risks facing the future development of the CPEC. Domestic instability in Pakistan, as well as intensifying strategic competition between the United States and China, could affect the future of the CPEC.

Impact of Urbanization on Indigenous Carnivorous Plants Species: A study from Bhubaneswar Smart City, Odisha, India

Carnivorous plants are wonder of nature which provides a wide aspect of research areas that can help to unlock evolutionary secrets. Around 860 unique species of flesh-eating plants are reported worldwide out of which 5 genera belong to 3 families of carnivorous plants are recorded in India. These plants are seen in areas with abnormal natural conditions and low nutrient supply. But in the modern technological era, due to human activities like urbanization, these plants are on the way to extinction. From the study, it was observed that large number of construction activities in study site urban areas like Bhubaneswar smart city can greatly alter abiotic and biotic components of the native ecosystem. The carnivorus plants play an important role as ecological indicator. Construction of large scale infrastructure in the name of urbanization causes reduction in indigenous species and terrestrial insect diversity which alternately promoting the proliferation of exotic species (BCA- 0.466; ACA- 0.483) and threat to carnivorous plant diversity.

Mongolia's "New Revival Policy": infrastructure priorities

The article examines the features of the “New Revival Policy” of Mongolia - the first stage of the long-term strategy “Vision - 2050”. The policy marks an important step in adjusting economic policy in the face of global challenges and aims to encourage Mongolia’s post-pandemic recovery by opening up the country to domestic and foreign investment. The author analyzes the six priority areas of new policy: the revival of the border checkpoints, energy, industrialization, urban and rural recovery, green development, and public sector efficiency. The author briefly examines the recovery of border crossings, transport and logistics network of Mongolia, including the construction of railways, the opening of international airports, the establishment of “dry ports”, etc. The author highlights the specifics of foreign trade and related cargo flows, notes the extreme relevance of large-scale infrastructure construction and upgrading. In addition to ensuring conditions for effective foreign trade, it is important for Mongolia to use its advantages as a transit territory, especially in the current period, when China is actively promoting overland cargo transportation to Europe, and Russia is focusing on the eastern direction. Mongolia intends to speed up the launch of new railway and road corridors: the plans of the “New Revival Policy” include the construction of the Choibalsan – Khuut – Bichigt railway in the east and the Arts-Suur – Nariinsukhait – Shiveekhuren railway in the west. Thereby, a favorable environment for strengthening Mongolia’s infrastructure connectivity with neighboring countries will be formed what is an important condition for the development of the China-Mongolia-Russia Economic Corridor.

Search on Risk Assessment of PPP Project Financing Based on ISM-FAHP Model

With the rapid development of China's economy, the demand of large-scale infrastructure construction projects is increasing day by day, but the shortage of funds has become the bottleneck restricting the progress of projects. In order to solve this problem, the Chinese government has gradually implemented the PPP project financing model in the field of infrastructure to attract social capital to participate and share the risk. However, with the implementation of this model, the problem of financing risk has gradually become prominent. Therefore, this study aims to provide scientific theoretical support and practical suggestions for relevant decision-making through in-depth analysis of PPP project financing risk and application of ISM-FAHP model.

Discussion on the Application of Integrated Aerogeophysical Method in Urban Site Selection and Construction

As the construction of "Belt and Road Initiative" continues to advance, cities and large-scale infrastructure construction will be ushered in along the route, and there is an urgent need to quickly identify the geological situation of the engineering survey needs. Aerial physical prospecting has the characteristics of high efficiency and low cost, which can quickly identify the regional geology in a large area and provide geophysical basis for urban site selection and construction decisions, and has great potential in China’s "Belt and Road Initiative" construction.

The Spatiotemporal Variation Characteristics of Urban Sustainability Based on the SDGs in Yangtze River Delta, China

At present, most developing countries need to improve the quality of the built environment by means of large-scale infrastructure construction, thereby promoting rapid urbanization. The quality of the built environment (QU) and its environmental pressure (PU) have become our primary focus to achieve a globally acknowledged vision of the Sustainable Development Goals (SDGs). In this study, we proposed an overall workflow by combining the proven urban sustainability (SU) assessment tool with the evaluation process and the analysis of the spatiotemporal dimension to investigate the urban characteristics of the 41 cities in the Yangtze River Delta. Our results showed an upward trend of urban sustainability from 2010 to 2018, but there are still 19 cities with unsustainable urbanization processes. The megalopolis is rapidly progressing toward an imbalanced state. Specifically, the urban sustainability of the southern region performs better than the northern region, coastal cities perform better than the inland cities, and the regional peripheral cities perform better than the inner cities. Across the 41 cities in the delta, five different relational trends between QU and PU have been found to predict their future development. The results of this research will help decision-makers to coordinate the future development of regional integration between cities and to target the alleviation of the adverse chain reaction brought about by the situation of imbalance or further improving urban sustainability.

Preparation of a Transient Thermal Expansion Rock Cracking Agent by Deposition Method and Its Nonisothermal Kinetics Study with Isoconversional Procedure and DAEM.

Cracking agents are indispensable and important products for national energy exploitation and large-scale infrastructure construction. Transient thermal expansion rock cracking agent is a new cracking agent product with excellent performance that has just appeared in recent years. However, it is still prepared by mechanical ball milling, which is considered not the best choice among traditional methods for preparing energetic materials. In this paper, a transient thermal expansion rock splitting agent was prepared by the chemical deposition method using carbon black and calcium peroxide as raw materials. The TG/DTG results show that the mass loss of the sample can be divided into four stages with the increase of temperature. It is worth noting that the mass loss of the TG curve of the sample during the entire thermal decomposition process is 93.385%, and the instantaneous weight loss is 78.07% (β = 15 °C/min). Kinetic analysis of the thermal decomposition process of the samples was performed using an isotransformation program and a distributed activation energy model (DAEM). The activation energy E α of the thermal decomposition of the sample was iteratively calculated. The results show that the a-E a curve of the sample can be divided into two stages. The pyrolysis kinetics of the first stage was successfully analyzed by the DAEM method and its thermal conversion behavior was predicted. The thermal decomposition behavior of the second stage was analyzed by a traditional kinetic analysis method.

Research on Detection and Safety Evaluation System of Huimin Lane Bridge based on BIM

With the continuous improvement of the national social and economic level the size and quantity of various types of infrastructure in our country have been improved and the community has put forward higher requirements on the level and quality of the construction. In recent years the bridge collapse accidents occur frequently, but our country bridge inspection and safety assessment of the system was established late, our country bridge structure health monitoring system research and application began in the 90. of the 20th century, the implementation of large-scale infrastructure construction projects, bridge health monitoring system also will be rapid development this paper discusses the based on BIM bridge inspection and safety assessment system, and puts forward some practical measures, provides the reference for improving bridge inspection and safety assessment of the system operation level.

3D Point Cloud Generation Based on Multi-Sensor Fusion

Traditional precise engineering surveys adopt manual static, discrete observation, which cannot meet the dynamic, continuous, high-precision and holographic fine measurements required for large-scale infrastructure construction, operation and maintenance, where mobile laser scanning technology is becoming popular. However, in environments without GNSS signals, it is difficult to use mobile laser scanning technology to obtain 3D data. We fused a scanner with an inertial navigation system, odometer and inclinometer to establish and track mobile laser measurement systems. The control point constraints and Rauch-Tung-Striebel filter smoothing were fused, and a 3D point cloud generation method based on multi-sensor fusion was proposed. We verified the method based on the experimental data; the average deviation of positioning errors in the horizontal and elevation directions were 0.04 m and 0.037 m, respectively. Compared with the stop-and-go mode of the Amberg GRP series trolley, this method greatly improved scanning efficiency; compared with the method of generating a point cloud in an absolute coordinate system based on tunnel design data conversion, this method improved data accuracy. It effectively avoided the deformation of the tunnel, the sharp increase of errors and more accurately and quickly processed the tunnel point cloud data. This method provided better data support for subsequent tunnel analysis such as 3D display, as-built surveying and disease system management of rail transit tunnels.

Tracing the Trends of General Construction and Demolition Waste Research Using LDA Modeling Combined With Topic Intensity.

The study of construction and demolition waste (CDW) has attracted more and more attentions with the increasing CDW pollution caused by the large-scale infrastructure construction. This study used the Latent Dirichlet Allocation (LDA) combined with topic intensity to discover hot topics and development trends in the study area of CDW. First, the LDA was used for topic modeling to extract the existing topics from textual data. Second, the topic intensity was calculated for the extracted topics and the numerical values of the topic intensity represented the popularity of the topics. In this study, 4 topics were extracted from 1,849 relevant articles through the LDA modeling and topic intensity calculation. The results showed that the topic of “CDW management” had an upward trend. Topics such as “recycled aggregate,” “environmental impact,” and “study of CDW on soil” all showed a downward trend. The methods of this study can dig into the topics of CDW study and help scholars to engage in this field for better understanding the prevalence and evolution trends of these topics.

Spatial and temporal analysis of the increasing effects of large-scale infrastructure construction on the surface urban heat island

With the rapid development of China's economy and the continuous improvement of people's living standards, large-scale infrastructure constructions (LSICs) are also increasing rapidly. LSICs with impervious surfaces have increasingly resulted in replacing natural landscapes, altering surface radiation, thermal properties, and humidity in urban areas. To study the environmental thermal changes of Beijing Daxing International Airport before and after its construction and operation, four Landsat-8 images (from the year of 2014, 2017, 2019, and 2021) were used to calculate the land surface temperature (LST). Then the LST values of four images covering the study area were compared and analyzed using the urban heat island ratio index (URI). Results show that the URI value of this area increased from 0.120 of 2014 to 0.185 of 2017 after the construction of Daxing Airport, indicating that the urban surface heat island effect in this area greatly increased. Additionally, the URI value of this area increased from 0.153 of 2019 to 0.206 of 2021 after the operation of Daxing Airport, indicating that the surface urban heat island effect in this area further increased. Therefore, we infer that this effect is closely related to airport construction and operation. Afterward, the random forest classification algorithm is used to classify land types based on pixels, and then the relationship between URI and land classification types was discussed. It is found that before the construction of Daxing Airport, both dark buildings and bare land contribute significantly to the thermal environment of the airport. After the completion of Daxing Airport, the contribution model was changed to high-reflectivity buildings and bright soil. The thermal pollution generated by the airport has a greater impact on the ground objects within the range of 7.5 km, and a relatively smaller impact on the ground objects outside the range of 9.5 km. Our results can provide a valuable reference for the study of the thermal environment caused by human activities.

Effect of adding solid waste silica fume as a cement paste replacement on the properties of fresh and hardened concrete

Due to the large-scale infrastructure construction and environmental protection pressure in China, the demanded cement is in short supply and the price is rising, and the overcapacity of silica fume has caused its price to fall, thus replacing cement paste by silica fume could achieve better economic and environmental benefits. In this study, silica fume (SF) with SiO2 content of 86.3% and high purity silica fume (HSF) with SiO2 content of 96% were used to replace cement paste in different proportions. The effects of adding SF or HSF on the workability of fresh concrete, the mechanical properties and microstructure of hardened concrete were investigated. The microstructures (i.e., porosity, pore size distribution and micromorphological characteristics) were analyzed by using low field nuclear magnetic resonance (LF NMR) and field emission scanning electron microscopy (FE-SEM). The results showed that the slump and air content of the concrete gradually decreased as the amount of SF or HSF increased. When the replacement amount of SF was increased from 0% to 10%, the cubic compressive strength and splitting-tensile strength of concrete were increased by 26.7% and 40.7%, while the cost per cubic meter of concrete was only increased by 1.9%. When the replacement amount of HSF was increased from 0% to 10%, the cubic compressive strength and splitting-tensile strength of concrete were increased by 44.7% and 57.4% respectively, while the cost per cubic meter of concrete was only increased by 5.3%. The total porosity of concrete gradually decreased as the amount of SF or HSF increased, with the proportion of macropores (>1000 nm) decreasing, and the proportion of mesopores (100–1000 nm) and capillary pores (0–100 nm) increasing, significantly refining the pore structure and densifying the microstructure of concrete.

Effects of Urban Vibrancy on an Urban Eco-Environment: Case Study on Wuhan City.

In the context of rapid urbanisation and an emerging need for a healthy urban environment, revitalising urban spaces and its effects on the urban eco-environment in Chinese cities have attracted widespread attention. This study assessed urban vibrancy from the dimensions of density, accessibility, liveability, diversity, and human activity, with various indicators using an adjusted spatial TOPSIS (technique for order preference by similarity to an ideal solution) method. The study also explored the effects of urban vibrancy on the urban eco-environment by interpreting PM 2.5 and land surface temperature using “big” and “dynamic” data, such as those from mobile and social network data. Thereafter, spatial modelling was performed to investigate the influence of urban vibrancy on air pollution and temperature with inverted and extracted remote sensing data. This process identified spatial heterogeneity and spatial autocorrelation. The majority of the dimensions, such as density, accessibility, liveability, and diversity, are negatively correlated with PM 2.5, thereby indicating that the advancement of urban vibrancy in these dimensions potentially improves air quality. Conversely, improved accessibility increases the surface temperature in most of the districts, and large-scale infrastructure construction generally contributes to the increase. Diversity and human activity appear to have a cooling effect. In the future, applying spatial heterogeneity is advised to assess urban vibrancy and its effect on the urban eco-environment, to provide valuable references for spatial urban planning, improve public health and human wellbeing, and ensure sustainable urban development.

Interferometric coherence and seasonal deformation characteristics analysis of saline soil based on Sentinel-1A time series imagery

Affected by the natural environmental and human activity factors, significant seasonal differences appear on the regional scattering characteristic and ground deformation of saline soil. Interferometric decorrelation due to season replacement limits the conventional multi-temporal interferometric synthetic aperture radar (MT-InSAR) technique and its application in such areas. To extend the monitoring capability in the salt desert area, we select a vast basin of saline soil around Howz-e-Soltan Salt Lake of Iran as the study area and present an improved MT-InSAR for experimental research. Based on 131 C-band Sentinel-1A images collected between October 2014 to July 2020,1896 refined interferograms in total are selected from all interfero-gram candidates. Interferometric coherence analysis shows that the coherence in the saline soil area has an apparent seasonal variation, and the soil moisture affected by the precipitation may be the main factor that leads to the seasonal variation. Subsequently, the deformation characteristics of saline soil under different environmental conditions and human activity factors are compared and analyzed in detail. Related deformation mechanisms of different saline soil types are initially revealed by combining interferometric coherence, meteorological data, and engineering geological characteristics of saline soil. Related results would provide reference for the large-scale infrastructure construction engineering in similar saline soil areas.

Retraction Note: Slope rainfall environment characteristics based on target tracking algorithm and economic efficiency of green city

With the rapid development of China’s economic construction, large-scale infrastructure construction has been carried out in the slope area. However, due to the poor geological environment, concentrated rainfall, and limited land resources in the region, a large number of slope toe excavation and graded slope cutting are carried out in the process of engineering construction. The unreasonable excavation method destroys the original slope shape and affects the stability of the slope, which brings many geological disasters in the loess area. Therefore, it is of great significance to analyze the influence of rainfall and excavation on the deformation and stability of loess slope. Considering the practical application, this paper also considers the target tracking on FPGA. The target tracking algorithm on FPGA must be reliable, real-time, meet certain tracking accuracy, and have certain operability. The proposed target tracking algorithm combines Harris method and optical flow method. Firstly, Harris method is used to extract some target angle features, and then optical flow method is used to match angle features more accurately for subsequent video frames. When the target is rotated or twisted, the barycenter algorithm is used to calculate the barycenter of the matching features. Based on the above research, this paper draws the following conclusions: the overall level of green economy efficiency is unbalanced; There is a U-shaped relationship between urban economic development and environmental pollution; The main influencing factors of urban green development efficiency are industrial structure, economic development degree, opening degree, financial development level, and human capital.

Application and validation of the fugitive dust source emission inventory compilation method in Xiong'an New Area, China

The development of a refined fugitive dust emission inventory is vital for prevention and control of air pollution. In this study, a fugitive dust emission inventory of soil dust (SD), road dust (RD), and construction dust (CD) in Xiong'an New Area (XANA) for 2020 was developed by collecting activity data and combining remote sensing and field investigation data based on a popular compilation technology in China. The CALPUFF model was used to elucidate the contribution characteristics of dust sources to ambient particulate matter (PM), and the accuracy of the dust emission inventory compilation method was verified. The results show that the total emissions of PM10 and PM2.5 were 43,081.14 tons and 9701.69 tons, respectively. Meanwhile, RD and CD were the main emission sources, accounting for over 98.49% of the total emissions. The total contribution from the different types of dust sources to the ambient PM10 was 42.59 μg/m3 (29.38%), with the contribution of RD (32.63 μg/m3, 22.51%) being approximately three times that of CD (9.78 μg/m3, 6.74%). Roads were the main source of fugitive dust, but large-scale infrastructure construction was the main cause of the high emission and high contribution of RD. The results show that the emission inventory compilation method can be used to estimate the emissions of dust sources, while the method used to calculate the emission of SD may be more suitable for dry and semi-dry areas with less rainfall. It was also found that when the dust emissions stay stable, the contribution of dust sources to the ambient PM10 in different seasons can vary by 3–4 times. Therefore, under adverse meteorological conditions, it is necessary to strengthen the control of various dust sources and reduce the influence of human factors on them.