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The growth of cities induced an increased demand for infrastructure including tunnel constructions. Because the urban ground usually is soft soil therefore tunnel constructions may cause ground settlement and damage the structures around. So, it is very important to carefully consider the tunnel construction effect on the design, construction, operation, and risk assessment of structures around the tunnel. In this paper, the finite element method was used to study the influence of the tunnel excavation on beneath piled buildings at the Hanoi metro line 03. These results indicate that the internal forces and displacements of the pile are greatest for the front pile closest to the tunnel in the group, which is the first pile to be loaded in the group. Two parameters: the tunnel burial depth and the distance from the tunnel centreline to the beneath-piled building have been investigated. These results found that the distance from the tunnel axis to the beneath piled building increases, while both the internal forces and displacements of the pile decrease. These internal forces and displacements increase with greater tunnel burial depth. The magnitude of normal forces and bending moments in the tunnel lining increase as the tunnel burial depth increases, while normal forces increase and bending moments in the tunnel lining decrease when the distance from the tunnel axis to the beneath-piled building decreases.

The underground space development is associated with the emergence of complex and dangerous situations, often leading to accidents. The condition for their development is the potential geotechnical risks. High-quality execution and analysis of design work at all the stages of design, starting from the early stages, is one of the effective ways to control risks. Clarification of the characteristics and features of the rock mass adjacent to the projected underground structure makes it possible to identify the potential cause of the occurrence of an adverse event with a certain probability during the construction and operation of an underground structure. The purpose of a qualitative risk analysis is to identify risk factors in underground construction. The value of the total geotechnical risk, expressed by the sum of each of the possible risks, should be numerically estimated at the design stage of a specific underground facility. At the same time, it is extremely important to develop a methodology for managing geotechnical risks, which would make it possible to assess their probability of development at an early stage of project preparation and propose measures to reduce or prevent them. This technique is given in the article. The results of the study conducted in accordance with the presented methodology showed that geotechnical risk control proved an effective method in preventing accidents during underground construction.

Investigation of mining-induced stress is essential for the safety of coal production. Although the field monitoring and numerical simulation play a significant role in obtaining the structural mechanical behaviors, the range of monitoring is not sufficient due to the limits of monitoring points and the associated numerical result is not accurate. In this study, we aim to present a spatial deduction model to characterize the mining-induced stress distribution using machine learning algorithm on limited monitoring data. First, the framework of the spatial deduction model is developed on the basis of non-negative matrix factorization (NMF) algorithm and optimized by mechanical mechanism. In this framework, the spatial correlation of stress response is captured from numerical results, and the learned correlation is employed in NMF as a mechanical constrain to augment the limited monitoring data and obtain the overall mechanical performances. Then, the developed model is applied to a coal mine in Shandong, China. Experimental results show the stress distribution in one plane is derived by several monitoring points, where mining induced stress release is observed in goaf and stress concentration in coal pillar, and the intersection point between goaf and coal seam is a sensitive area. The indicators used to evaluate the property of the presented model indicate that 83% mechanical performances have been captured and the deduction accuracy is about 92.9%. Therefore, it is likely that the presented deduction model is reliable.

Introduction. With the time of operation of buildings and structures, soil compaction occurs under the base of their foundations from all the acting loads from the building. The purpose of the research is to study the movements of the building foundations during the construction of the underground part with their possible preventive reinforcement during reconstruction, taking into account changes in the strength and deformation characteristics of soils. The solution of this problem will allow the most detailed consideration of buildings settlement during reconstruction.Materials and methods. A series of numerical calculations in the PLAXIS 2D software package of the interaction of the foundation with the foundation soil during the reconstruction of a building with the development of underground space, including the construction of two or three underground floors, were carried out.Results. The effect of taking into account the improved soil characteristics with regard to the time of building operation on the settlement of existing foundations during reconstruction with the development of underground space is studied. It was revealed that the reinforcement of foundations with soil-cement elements reduces the settlement during reconstruction approximately in two times. The influence of the number of floors of the designed underground car park on the stress-strain state of the soil massif is considered.Conclusions. Numerical studies show that strengthening of soils under the base of existing foundations leads to a decrease in the building settlement during reconstruction with the development of underground space. Reinforcement of the existing foundation with soil-cement elements makes it possible not to exceed the maximum additional settlement of the reconstructed building. A decrease in the settlement of existing foundations with a decrease in the number of storeys of the designed underground part is revealed.

The construction of public buildings involves a significant amount of carbon emissions, particularly during the materialization phase of underground construction, which is characterized by a rapid and intense release of carbon emissions. In response to this issue, this study aims to develop a Building Information Modeling (BIM)-based method for assessing the factors influencing carbon emissions during the materialization phase of underground construction in public buildings. To achieve this goal, a process-based quantitative and qualitative method was established to evaluate carbon emissions at various stages, including raw material extraction and processing, building material/equipment production, and on-site processing of components, as well as construction and installation. The proposed method may serve as a valuable tool for selecting design schemes in the early stages of building design. By analyzing 125 actual cases in Xi’an, China and utilizing a carbon emission calculation model, accurate carbon emission data was obtained. This study’s findings indicate a correlation between the embodied carbon emissions and the area of underground space in the cases analyzed. Specifically, larger underground spaces were associated with higher embodied carbon emissions in underground engineering. Furthermore, this study categorized the cases into two groups based on the presence or absence of underground space, resulting in the identification of 16 factors for cases without underground space and 19 factors for cases with underground space. These findings provide valuable insights for understanding and mitigating the impact of carbon emissions during the materialization phase of underground construction in public buildings.

Introduction. For many decades there have already been attempts, and sometimes very successful, to create unique urban areas. But these areas were developed mainly as single variants on the formation of urban environment. Basically, they built areas of multi-story buildings according to the average requirements for the comfort of the urban environment. In the modern world, these areas no longer meet the requirements of living and require renovation in accordance with the modern concepts of comfortable living. A study based on Russian and foreign urban planning projects of renovation of areas with mass multi-story buildings is presented.Materials and methods. Based on the analysis of domestic and foreign urban planning experience in the formation of comfortable living environment in the districts and neighbourhoods of large cities, a conceptual project of comprehensive renovation of urban areas of mass construction of 1960s–2000s is proposed.Results. On the example of the Lesoparkovaya metro area the concept of renovation of the area, creation of more comfortable living environment, attraction of holidaymakers, new residents, workers to new jobs to the areas by creating a structure — attractor with development of underground space is presented. Presented two concepts of this structure will attract people to visit the district and use public transport, namely — metro Lesoparkovaya, Butovskaya line.Conclusions. The presented concept can serve as a baseline for the renovation of neighbourhoods with mass development. This requires a so-called attractor, which will attract certain segments of the population, as well as a comprehensive development of the whole neighbourhood. It is necessary that the concept of the neighbourhoods should not be repeated and should be unique. Therefore, everyone will be able to find a rest area, living and working area according to their interests.

This study demonstrates the design and field implementation of an innovative servo concrete bracing system in foundation pit excavation. The bracing system comprises concrete struts, revised purlins, and hydraulic jacks, and its field performance is evaluated in a deep foundation pit project in Shanghai, China. The field measurements demonstrate that the servo bracing system effectively reduces the maximum lateral displacement of the retaining wall by up to 31%. Moreover, the servo jacks modify the wall’s flexural behavior by introducing local inflection points at certain depths and driving the displacement peak upward. Furthermore, the system’s performance varies with strut configuration, and servo forces influence not only the corresponding acting strut but also the adjacent struts’ behavior, implying that the monitoring scope should be expanded when applying the servo bracing system in actual engineering. This study provides a meaningful technical reference for future servo concrete bracing system applications in foundation pit engineering.

Engineering construction changes the groundwater flow field and endanger the safety of buildings. Taking the large-scale underground complex along Jinan Jingshi Road as an example, the impact of engineering construction on the groundwater seepage field is obtained by numerical simulation, and the groundwater flow field repair models are established. These results show that the underground spatial structure will block the normal movement of groundwater, and will reduce the bearing capacity of the foundation after the groundwater level is raised. After adding diversion measures to the underground space, the water level at the upstream surface will decrease with time, and the closer it is to the natural state, the slower the water level attenuation rate is. Due to the difference in the stratum structure, there is a great difference in the time when the backwater level basically drops. The number of diversion wells required to repair the flow field under different geological conditions has a negative correlation with the structural parameters of diversion geometry. The established equation for predicting the number of diversion wells fully reflects the complexity and variability of geological conditions in karst areas. In addition to the structure of the fluid conducting geometry, the hydraulic gradient and permeability coefficient of the surrounding rock also affect the water conducting capacity of diversion measures. The permeability coefficient controls the speed of the water conducting rate, while the hydraulic gradient controls the occurrence of water conducting behavior. The implementation of diversion measures can reduce the impact of engineering construction on the groundwater environment and ensure that the impact of underground engineering construction on the water environment is controllable.

In geotechnical engineering, the transparent soil (also called transparent media) technique is an effective tool for conducting experimental tests and investigating the displacement characteristics and stress distribution of soils. It plays a vital role in the observation of internal soil deformations. This study aims to briefly review the current state of some of the common materials used to formulate transparent soil models and the application of the transparent soil technique to underground construction over the last 20 years. To this end, the basic concepts of transparent soils are introduced. Then, several representative applications of transparent soil in underground construction (i.e., soil deformations induced by the penetration of pile foundations, tunnel excavation-induced movements, and structural responses caused by braced excavations) are presented. Because some research gaps may exist, certain potential research topics are proposed. This review can serve as a guideline for researchers performing experiments using transparent soils.

Tunneling in urban conditions requires costly measures, in order to ensure the safety of existing buildings. On average, there are up to 17–20 buildings per 1 km of Moscow Subway Lines under construction. Analysis and comparison of geotechnical monitoring data and results of geotechnical estimations for underground construction using cut-and-cover and tunneling methods in conditions of high-density urban area shows an unsatisfactory correlation between estimated and actual data. This can be described in the following way: insufficient geotechnical survey data; discrepancy between the accepted estimation model and the actual behavior of soil under load; insufficient qualification of the construction workers; and overcutting. The study was aimed at solving the urgent scientific and engineering problem of determining the characteristics of overcutting during mechanized tunnel boring. At the first stage, the investigations were aimed at identifying the key reasons and factors which determine the quantitative parameters of overcutting in urban underground construction by tunneling. These factors include the following: mismatch between the cutting diameter and the outer lining diameter; displacement of the soil mass in front of the face; incomplete grouting of voids beyond the lining; incomplete filling of beyond-shield voids with clay mortar or slow-curing grouting mortar or no filling at all; and human factor (low qualifications of personnel). The overcutting coefficient was determined on the basis of the proposed empirical dependence of its values with regard to the depth of tunneling. The experimental data allowed the depth dependence of the overcutting coefficient for different tunneling depths to be defined, as well as for tunnel diameters from 4 to 10 meters in the case of mechanized tunnel boring machine (TBM) using the earth pressure balanced tunneling method. The practical importance of the studies consists in determining the range of the empirical overcutting coefficient variation from 0.5 % (for TBMs with nominal diameter of 10 m) up to 5 % (for TBMs with nominal diameter of 4 m). The development of organizational measures and justification of process solutions, aimed at ensuring the safety of the existing buildings in conjunction with the scientific and technical support of underground construction has led to a shortening of tunneling time between the Okskaya and Nizhegorodskaya stations of Nekrasovskaya Line of Moscow Subway by about six months. It has also provided savings of about 2.5 billion rubles.

The capacity of aquifers to store water and the stability of infrastructure can each be adversely influenced by variations in groundwater levels and subsequent land subsidence. Along the south bank of the River Thames, the Battersea neighbourhood of London is renovating a vast 42-acre (over 8 million sq ft) former industrial brownfield site to become host to a community of homes, shops, bars, restaurants, cafes, offices, and over 19 acres of public space. For this renovation, between 2016 and 2020, a significant number of bearing piles and secant wall piles, with diameters ranging from 450 mm to 2000 mm and depths of up to 60 m, were erected inside the Battersea Power Station. Additionally, there was considerable groundwater removal that caused the water level to drop by 2.55 ± 0.4 m/year between 2016 and 2020, as shown by Environment Agency data. The study reported here used Sentinel-1 C-band radar images and the persistent scatterer interferometric synthetic aperture radar (PSInSAR) methodology to analyse the associated land movement for Battersea, London, during this period. The average land subsidence was found to occur at the rate of −6.8 ± 1.6 mm/year, which was attributed to large groundwater withdrawals and underground pile construction for the renovation work. Thus, this study underscores the critical interdependence between civil engineering construction, groundwater management, and land subsidence. It emphasises the need for holistic planning and sustainable development practices to mitigate the adverse effects of construction on groundwater resources and land stability. By considering the Sustainable Development Goals (SDGs) outlined by the United Nations, particularly Goal 11 (Sustainable Cities and Communities) and Goal 6 (Clean Water and Sanitation), city planners and stakeholders can proactively address these interrelated challenges.

Frequent anthropogenic activities associated with rapid urbanization may cause ground subsidence and endanger the adjacent buildings. Interferometric synthetic aperture radar (InSAR) has generated dense measurement points for large-scale deformation monitoring and risk assessment. However, the applications of InSAR for building deformation and risk level prediction are still rare, especially under complex loading scenarios. In this study, we present an integrated method to monitor and predict building deformation and risk levels using multi-temporal InSAR and numerical modeling. Persistent and distributed scatterers were jointly detected to monitor deformation using TerraSAR-X, COSMO-SkyMed, and Sentinel-1 images over the Kowloon district of Hong Kong and the Futian district of Shenzhen. First, the building risk level was assessed at the district scale using ground subsidence and angular distortion to identify potentially damaged buildings. 10 out of 807 buildings in the Kowloon and 2 out of 145 buildings in the Futian were classified as medium risk. Back-analysis was used to retrieve the geological and hydrological conditions of buildings at the medium risk level. Then, time-series subsidence of the Lucky and BMW buildings during 2012 to 2016 and the Jingli building during 2010 to 2014 was simulated by numerical modeling, which agreed well with the InSAR measurements. By defining the groundwater level changes and upper loading, the predicted subsidence of the Lucky, BMW, and Jingli buildings reached 47.9, 62.8, and 39.9 mm by 2021, respectively, with a decelerated trend. Time-series results showed that the Lucky and BMW buildings were still at the negligible-to-medium risk level in 2021, and should be constantly inspected; the risk level of the Jingli building became negligible from 2020. This method can be transferred to other rapidly urbanized areas prone to ground subsidence for geohazard assessment and improve the understanding of the dynamic behaviors of anthropogenic activity-induced ground subsidence.

The Urdinbide road tunnel goes through the Autzagane aquifer. This important aquifer is located within the hydrogeological area of the Urdaibai Biosphere Reserve, one of the most important biosphere reserves in the Iberian Peninsula, and it is also used as a source of drinking water for some urban areas in the municipality of Amorebieta-Etxano. The construction of the tunnel could pose a potential risk to the normal functioning of the aquifer, so its design included a special procedure for injecting cement and microcement to waterproof the surrounding area of the drilling, preventing the tunnel from functioning as a drain for the aquifer. The project initially included an intensive hydrogeological characterization of the rock massif, as well as a monitoring phase during the construction works, which allowed a real-time verification of the influence of the tunnel construction on the functioning of the aquifer and the restoration of its normal functioning once the works were completed. The work carried out has shown that the construction of the tunnel has not caused a significant impact on the Autzagane aquifer.

The system approach to the underground construction objects planning based on foresight and cognitive modeling methodologies is proposed. Using the foresight methodology allows with the help of expert estimation procedures to identify critical technologies and build alternatives of scenarios with quantitative characteristics. For the justified implementation of a particular scenario the cognitive modelling is used, which allows to build causal relationships based on knowledge and experience, understand and analyze the behaviour of a complex system for a strategic perspective with a large number of interconnections and interdependencies. The suggested system approach allows planning of underground objects on the basis of reasonable scenarios selection and justification of their creation priority.

Underground constructions are implemented in cities to relieve the pressure of urbanization. Ground deformation often occurs with improper construction activities. Such deformation can be measured with techniques such as multitemporal interferometric synthetic aperture radar (MT-InSAR). However, the deformation anomalies, such as the building horizontal tilt can cause the MT-InSAR line-of-sight deformation to tend to zero, the deformed area is likely to be ignored when the individual SAR dataset is applied. In this article, we explore deformation induced by the underground construction of To Kwa Wan (TKW) station in Hong Kong with an improved MT-InSAR method. Multiplatform SAR datasets from TerraSAR-X, COSMO-SkyMed, and Sentinel-1A are adopted to retrieve comprehensive deformation of ground buildings for stability investigation. The results are validated through cross-validation between SAR datasets. Both spatial and temporal variations of ground deformation are revealed. Ground buildings suffered significant deformation in vertical and horizontal directions, the maximum deformation is around 30 and 40 mm, respectively. Due to the anomalous deformation, the ground buildings around the station are dumped towards the street center. In view of temporal evolution, the deformation is strongly related to the construction stages. The deformation turned to be stable after the completion of the main framework of the TKW station in December 2016. This article suggests that the deformation obtained from individual SAR datasets may sometimes is not noticeable or reliable in the area with complex underground construction. Such complex phenomena can be revealed by using the multiplatform SAR datasets with MT-InSAR.

This paper addresses the gap in the scientific literature regarding construction cost estimates for the construction of underground metro stations. It provides preliminary cost estimation models using linear regression for use by the Greek underground metro public transport authority for planning future extensions to the Athens and Thessaloniki networks. At the same time, it contributes to the body of knowledge by proposing material quantity prediction models and presents a two-stage preliminary cost estimation model for the construction of civil engineering works of underground metro stations. Stage one uses the construction cost budgets of six metro stations in Greece to develop a multilinear regression equation for the prediction of the overall cost for construction of civil engineering works; stage two provides estimates of material quantities using linear regression, key quantity ratios, and artificial neural networks. The data analyzed are from the prior measurements of quantities for the construction of the Chaidari to Piraeus extension of the Athens Metro Line 3. After comparing the actual values of costs and quantities with the corresponding predictions, acceptable discrepancies are observed. All models provide estimates within ±25% discrepancies, which are acceptable at the conceptual planning phase in order to initiate project funding quests.

Background. The geological conditions of the Russian site for deep burial of radioactive waste near the Yenisei are considered. Not only isolated within the boundaries of a given site, as was the case before. But also taking into account more ambitious factors: tectonics of lithospheric plates, properties of a number of functionally similar sites in transitional conditions (Baltic–Yenisei–Pacific Ocean), zoning of the local adjacent territory by mineral resources, the presence of other disposal facilities near the site. Materials and methods. In such a semantic connection, it is proposed to study at the exploration stage the main engineering-geological parameter of the rock mass for safety – the state of the underground hydrosphere. The need reliable regulatory and legal framework was noted. Results and conclusions. Based on the results of the initial stages of work on the deep disposal site for radioactive waste, shortcomings in the application and implementation of legislation and technical standards were identified. A proposal has been formulated for a legal examination of documents prepared for the Yeniseisky site.

A proper assessment of the stability leads to proactive decision making for the method of construction, the shape and size of the cross-section of the facility and the adequate support. The stability is directly dependent on the physical, mechanical and technical characteristics of the rock mass. The traditional assessment-based approach and the classification of stability of underground facilities is based on both experience and experiments with previously constructed facilities. To ease the process for the early phase of design, there was a need for the development of a mathematical model for assessment of the stability. Ambiguity in mining engineering, directs the development of the model using a fuzzy logic system and fuzzy "if-then" rules. The model was developed based on very scarce input data that is most often the only data available during the design stage. Fuzzy model results have shown, through the random selection of input data in the model, that in 70% of cases, there is high numerical congruence with the traditional method for determination of coefficient of stability S; and in 90% of cases, there is also congruence in accordance with the traditional approach to the classification of underground facilities based on the stability assessment.

The presented research conducted a bibliometric analysis regarding academic publications, especially journal publications, in the area of urban underground infrastructure (UI) systems (which include sewer pipes, drinking water pipes, cables, tunnels, etc.). In total, 547 journal papers published from 2002 to July 2022 (around 20 years period) were retrieved from Scopus using the proposed data collection method. Bibliometric analysis was conducted to extract and map the hidden information from retrieved papers. As a result, networks regarding co-citation, co-authorship, and keywords co-occurrence were generated to visualise and analyse the knowledge domain, patterns, and relationships. The eight most investigated topics in the UI research are identified and discussed, which provides an overview of the research history and focuses. Further, five potential research directions are suggested for researchers in the UI research area. The main contribution of this research is on revealing the knowledge domain of UI research in a quantitative manner as well as identifying the possible research directions.

The anionic surfactant sodium lauryl ether sulfate (SLES) is the main component of most commercial foaming agents (FAs) used in the excavation of highway and railway tunnels with Earth pressure balance-tunnel boring machines (EPB-TBMs). Several hundreds of millions of tons of spoil material, consisting of soil mixed with FAs, are produced worldwide, raising the issue of their handling and safe disposal. Reducing waste production and reusing by-products are the primary objectives of the “circular economy,” and in this context, the biodegradation of SLES becomes a key question in reclaiming excavated soils, especially at construction sites where SLES degradation on the spot is not possible because of lack of space for temporary spoil material storage. The aim of the present work was to apply a bacterial consortium (BC) of SLES degraders to spoil material excavated with an EPB-TBM and coming from a real construction site. For this purpose, the BC capability to accelerate SLES degradation was tested. Preliminary BC growth, degradation tests, and ecotoxicological evaluations were performed on a selected FA. Subsequently, a bioaugmentation experiment was conducted; and the microbial abundance, viability, and SLES concentrations in spoil material were evaluated over the experimental time (0.5, 3, 6, 24, 48, and 144 h). Moreover, the corresponding aqueous elutriates were extracted from all the soil samples and analyzed for SLES concentration and ecotoxicological evaluations with the bacterium Aliivibrio fischeri. The preliminary experiments showed the BC capability to grow under 14 different concentrations of the FA. The maximum BC growth rates and degradation efficiency (100%) were achieved with initial SLES concentrations of 125, 250, and 500 mg/L. The subsequent bioaugmentation of the spoil material with BC significantly (sixfold) improved the degradation time of SLES (DT50 1 day) compared with natural attenuation (DT50 6 days). In line with this result, neither SLES residues nor toxicity was recorded in the soil extracts showing the spoil material as a by-product promptly usable. The bioaugmentation with BC can be a very useful for cleaning spoil material produced in underground construction where its temporary storage (for SLES natural biodegradation) is not possible.

This paper presents a review of the advantages of application of JKSimBlast 2DFace software in design phase of underground premises. The aim of this research was to show possibilities of the software and possibility of its application in design of underground premises with suggestions for further work. A model of a drift "TIP 5" was developed and analysed in the software to show all the possibilities of the application of software in underground construction. Further work would require a detailed field work to gather input data required for more detail analysis of the effects of blasting in the software itself, as well as validation of the results given by software on the field.

The effect of pore water chemistry on anisotropic behavior of consolidation and shear strength of reconstituted Ariake clay has been investigated experimentally. Two types of chemicals added into the pore water of the soil for enhancing flocculation microstructure of soil particles are sodium chloride (salt) (NaCl), and calcium chloride (CaCl2); and two dispersants added are sodium triphosphate (Na5P3O10) and sodium hexametaphosphate (Na6P6O18), respectively. The concentrations of these chemicals in pore water were 2–3%. Degrees of anisotropy of the coefficient of consolidation and undrained shear strength decreased with adding NaCl and CaCl2, but increased with adding the dispersants. Degree of anisotropy also increased with one-dimensional (1D) deformation and the samples with dispersive additives had higher increase rate. It has been confirmed qualitatively by scanning electron microscopy (SEM) images that adding dispersive chemicals promoted the formation of dispersive microstructure and increased the degree of anisotropy, and the chemicals enhancing flocculent microstructure had an inverse effect. The possible application of the findings to underground construction has been discussed also.

A mine shaft steelwork is a three-dimensional frame that directs the vertical motion of conveyances in mine shafts. Here, we conduct field and numerical investigations on the stiffness and dynamic properties of these structures. Based on the design documentation of the shaft, materials data, and site inspection, the steelwork’s finite element model, featuring material and geometric non-linearities, was developed in Abaqus. Static load tests of steelwork were carried out in an underground mine shaft. Numerical simulations reflecting the load test conditions showed strong agreement with the in situ measurements. The validated numerical model was used to assess the dynamic characteristics of the structure. Dynamic linear and non-linear analyses delivered the natural frequencies, mode shapes, and structural response to dynamic loads. The current practices and regulations regarding shaft steelwork design and maintenance do not account for the stiffness of guide-to-bunton connections and disregard dynamic factors. Our experimental and numerical investigations show that these connections provide considerable stiffness, which leads to the redistribution and reduction in bending moments and increased stiffness of the construction. The results also show a high dynamic amplification factor. The omission of these features implicates an incorrect assessment of the design loads and can lead to over- or under-sized structures and ultimately to shortened design working life or failure.

This paper provides a brief overview of the methods and materials for injection in underground construction, with a focus on the use of new injection compounds for this purpose. The aim is to draw attention to the possibility of applying new materials for injection that are present in the world, which would facilitate the work, significantly shorten time of work and downtime.

Water–sand inrush disasters are frequently encountered during underground engineering construction in karst terrain. The objective of this paper is to study the failure mechanism and evolution characteristics of water–sand inrush caused by the instability of filling medium in karst cavity, as well as the impacts of soil compactness, hydraulic pressure and confining pressure on the instability process. In response to this purpose, a stress-controlled seepage test apparatus in consideration of particle loss was designed, and a series of seepage tests were performed correspondingly. The test results indicate that: (1) Based on the nonlinear feature analysis of water-outflow pattern, the water–sand inrush process can be divided into the “slow flow” stage, “transition flow” stage and “pipe flow” stage by Transition Point I, II. (2) The decreasing soil compactness and increasing hydraulic pressure both exponentially facilitate the seepage-erosion process by increasing the particle-erosion ability; the increasing confining pressure extends the “slow flow” stage and shortens the duration of the “transition flow” stage, ultimately advancing the occurrence of the “pipe flow” stage; the existence of critical hydraulic pressure for the seepage-erosion progress is confirmed, the occurrence of the “pipe flow” stage is significantly advanced once the hydraulic pressure over the critical value. (3) The particle loss caused by the seepage-erosion process is the internal mechanism of water–sand inrush, the variation characteristics of water-outflow pattern are crucial external manifestations correspondingly. Therefore, with the monitoring of water-outflow pattern variation tendency as indicators, the critical status of water–sand inrush can be near-real-time identified, which offers experimental foundation for the early warning and forecast of the occurrence of water–sand inrush.

In the construction community, underground construction is perceived as being significantly more costly and more energy-consuming than comparable surface construction. Although the literature is scarce, studies that have attempted to quantify this difference tend to compare built projects in heterogeneous conditions. The objective of this article is to present the results of life cycle cost and energy consumption simulations conducted as part of the Deep City project at the École Polytechnique fédérale de Lausanne in Switzerland. This article begins by examining the preconceptions the construction industry seems to have about underground construction as reported in the press from 2007 to 2017. Then, we present the method and results of two unpublished studies on the differences in costs and energy consumption of a hypothetical commercial building project in two different geological contexts. We find that energy consumption can be 15% higher but also 4% lower. We also find that underground construction in unconsolidated sediment ground is approximately 23% more expensive, while only 10% in bedrock, which is significantly lower than the 200% to 300% differentials reported in previous studies. We attribute this to the level of detail of our studies, the inclusion of ground conditions, and conclude that our results help to dispel certain misconceptions about underground construction, which can contribute positively to urban sustainable development goals.

Analysis of current legislation and jurisprudence practice shows that the use of underground space of cities creates a significant number of problems. In this article, we try to describe most typical of them. Recent research and publications analysis. The choice of the article's subject defined by importance of problems raised in it, some aspects of which are submitted in works members of land law study as P.F. Kulinich, R.I. Marusenko, A.M. Miroshnichenko A.I. Ripenko, N.V. Shulga and others. Paper objective. The article's subject is studying of a number of law issues for complex development of underground space. Paper main body. Today is a time to solve problems in the field of city development, we should refuse old forms of thinking and switch to the reasonable limits of vertical zoning, by increasing the permissible storeys, on the basis of deepspace organization of the whole system objects of development as the organic whole, which consists housing and all necessary social, industrial and engineering infrastructure, created in the underground level. Vertical zoning should be included in the zoning plans. It should be noted that in zoning plans must consider typology and characteristics of underground structures through the adoption of urban planning regulations. Except making changes in the zoning plans provisions about underground development, should also adopt plenty of standart acts or making additions to existing ones for underground construction. Since the law allows to decide the simultaneous operation of aboveground and underground parts of the land area, but only "to a certain extent", without giving specific and exhaustive answers to all questions that arise in this regard. There is also need to develop engineering-geological mapping of urban underground space that will allow to evaluate the possibility of a secure building in a particular location objects of underground space and significantly reduce the length of the stage frills building cycle. Underground spaces with objects placed on them are not subjects to registration as land and can not be displayed in the cadastral system. Thus, revealed itself the need to use some 3D features in existing cadastral system. The first step for introduction of this system are alreadey maded, in particular, introduced by the State Land Cadastre and the State registry, the next step will be introduction of accounting and registration of realty objects in three dimensions. Conclusions of the research. In Ukraine there are several problems that holds complex development of underground space. First of all, it is a complete lack of fundamental documents defining prospects in elaboration of underground construction. A lot of problems are in the technical regulation: there is no regulation requirements for construction of large number of objects just because earlier in Ukraine there were not built at all. In addition, there are no legislative acts regulating investment in the construction of underground structures, allocation of plots, obtaining ownership of the facility and more.

The article gives examples of underground construction of hydropower station inNepaland sewer tunnel in the USA. These projects pay attention to influence of geotechnical risks and their consequences.

A basic element in the decision making process on the adequacy of the support system was a monitoring and analysis process.We consider geomonitoring as continuous monitoring of objects (e.g. of mines, tunnels, machinery, buildings and a lot of constructions)during the construction or operating phase using geodetic, geotechnical and geophysical methods.Geomonitoring is gaining increasing significance as a result of new safety aspects, from the point of view of immission controlas well as in connection with early warning and alarm systems. Specific areas covered include geological and geotechnical explorationsrequired, construction of tunnels and shafts, design considerations, geomechanical analysis, design of linings, and instrumentationand monitoring.Consequently, monitoring of many of the instrument arrays have to continue for several years after construction. Monitoringprograms must be carried out for well-defined purposes, be well planned, and be supported by competent staff through completionand implementation of results from the monitoring program.

The procedure, technology and technique of erection of concrete timbering by the spill-concrete method are developed for conditions of mines in Germany.

The article analyses the manner of selection an optimal building technological project which would pander the majority of the concerned members (architects, customers, designers, contractors and so on) interests. Assessment technique is being considered and its features as well. The need to value the expenses associated not only with the construction period, but also with the exploitation period is explaned. A few examples are given about choosing a rational project considering not only the cost, but also some value factors that influence job quality or exploitation. Racionalių statybos technologinių procesų parinkimas taikant COPRAS metodÄ… Santrauka Straipsnyje analizuojama, kokiais bÅ«dais galime parinkti optimalų statinio statybos technologijos projektÄ…, kuris atitiktų daugumos suinteresuotų dalyvių (architektų, užsakovų, projektuotojų, rangovų ir kt. asmenų, susijusių su statinio gyvavimo ciklu) interesus. Aptariama, kokia turi bÅ«ti vertinimo metodika, kokiomis savybÄ—mis ji turÄ—tų pasižymÄ—ti. PaaiÅ¡kinama, kodÄ—l bÅ«tina įvertinti sÄ…naudas, susijusias net tik su statybos periodu, bet ir eksploataciniu laikotarpiu. Pateikiama pora pavyzdžių, kaip galima bÅ«tų iÅ¡rinkti racionalų projekto variantÄ… atsižvelgiant ne tik į piniginÄ™ iÅ¡raiÅ¡kÄ…, bet ir įvertinti kai kuriuos kitus veiksnius, turinÄius įtakos darbų atlikimo kokybei ar eksploatavimui. ReikÅ¡miniai žodžiai: požeminÄ— statyba, procesų parinkimas, daugiakriterinis vertinimas, COPRAS metodas First Published Online: 21 Oct 2010