Building Deformation Research Articles

STUDY ON THE IMPACT OF DEFORMATIONS OF MULTI-STOREY BUILDINGS IN ALMATY

The article provides an assessment of the stability of buildings and structures in the city of Almaty under the influence of frequent earthquakes. Studying this process is not only interesting from a scientific point of view but also has great practical significance for ensuring the safety and stability of buildings in the city. The aim of the work is to investigate the condition of buildings in Almaty in terms of seismic safety characteristics. The research tasks include studying the types of buildings common in the city of Almaty and conducting stability calculations for buildings. This article selects the main and most common type of buildings and structures in each district of the city of Almaty as the research object. The calculations of the level of buildings' stability to seismic vibrations in different areas of the city, information on the estimated seismic resistance level of most buildings, and the calculation of their possible stability indicators are provided. The results show that the stability of buildings and structures in the city depends on reducing seismic activity from bottom to top based on their location (on the map). According to the calculation conclusions, it is necessary to increase the number of design organizations responsible for construction quality and use different building structures and construction methods in different parts of the city. Problems related to building deformation are relevant everywhere. Studying this process in Almaty will contribute to the global knowledge base and help create new technical solutions for safe construction.

Study of the influence of spatial effects on the ground surface and buildings in a two-lane tunnel boring

There are a series of engineering risks, such as ground subsidence, building tilt and cracking, in the process of shield tunnel driving through buildings, which have many adverse effects on urban residents and engineers. In particular, the differences in the effects of the interaction of two-lane tunnels on the building structure and ground deformation field are less often considered under different spatial effects such as construction sequences and tunnel spacings. As well as the problem of analyzing the building as a whole out of reality. To solve these problems, the spatial effect of the shield tunnel underpassing the shallow foundation building is simulated by Plaxis3D software to study the sensitivity analysis of surface settlement and the internal forces and deformation law of the building above in the process of tunneling underpassing with different depths of burial H and horizontal distance D of the double line tunnel. The engineering impact zoning method can investigate the safety of tunnels and buildings under different spatial effects when tunnels pass through buildings. The splitting of the building into plates and columns can reveal the forces and deformation laws of different structural parts. The results show that during the construction process of the double-line tunnel, the tunnel constructed first has a “blocking effect” on the tunnel constructed later, which affects the distribution of the disturbance area to a certain extent and changes the curve shape of the settlement trough. When the “blocking effect” occurs, the surface settlement and building deformation will be significantly reduced. In the internal forces of the building, the plate structure is mainly subjected to changes in axial forces, while the column structure is mainly affected by shear forces and bending moments. The factor of safety of tunnels decreases as the tunnel spacing decreases and as the building loads above increase.

Monitoring of Architectural Monuments

The article presents the main provisions that it is advisable to follow when organizing and conducting monitoring during the operation of cultural heritage sites. It is noted that the existing regulatory documents do not take into account the specifics of monitoring during operation, but are mainly aimed at protecting the monument from neighboring construction.Criteria are proposed to control the technical condition of historical buildings. Among them is the rate of development of long-term precipitation, which is considered as an indicator of the intensity of natural and man-made impacts on the building.Among them is the rate of development of long-term precipitation, which is considered as an indicator of the intensity of natural and man-made impacts on the building. It is noted that for stone structures, critical masonry stretching deformations serve as an effective criterion for the preservation of historical buildings, since in calculating the interaction of structures and foundations they are the primary criterion for calculating the second group of limiting states. In relation to it, the criterion of absolute precipitation and relative difference of precipitation is secondary. It is shown that over time, for buildings built on weak water-saturated clay soils, an increase in the unevenness of precipitation occurs. Special attention is paid to taking into account the accumulated uneven precipitation of buildings of historical development. The article presents the most characteristic types of deformations of buildings, among which in St. Petersburg the bend is most common, which is due to the regularity of building and rebuilding sections of urban neighborhoods.Monitoring is also considered as a reliable means of diagnosing the technical condition of the monument. The monitoring function is considered as a means of controlling the limitations of the monument’s operability, which continues to be operated in conditions of limited operational technical condition.

Assessment method for deformation and structural damage of the masonry building caused by shield tunnelling

Assessment method for deformation and structural damage of the masonry building caused by shield tunnelling

Evaluation of building deformation monitoring using stereophotogrammetry method and Kalman filter model

Evaluation of building deformation monitoring using stereophotogrammetry method and Kalman filter model

Prediction of adjacent single pile deformation induced by tunnel excavation based on the Pasternak model

The construction of metro tunnels in soft ground would cause significant settlement of the ground surface and deformation of buildings and their foundations in the vicinity of the tunnels. The deformation laws of the pile of the neighbouring structures induced by the tunnel construction have not yet been fully identified. This paper analyzed the impact mechanism of tunnel construction on piles based on the Pasternak model, deduced the calculation methods of additional horizontal displacement and additional internal force of piles, and introduced three solution methods. The computational method results have been validated through numerical simulations using coupling of discrete element method and finite difference method and compared to select laboratory data. The results show that the model accuracy is better when the tunnel axis burial depth is less than the pile bottom burial depth. The analysis shows that the tunnel burial depth significantly influences the displacement distribution of the adjacent single pile, while the impact on the peak displacement is insignificant. The thickness of the elastic layer (C) is inversely related to the maximum horizontal displacement and internal force, but it does not impact the distribution patterns of the displacement and internal force. For thickness of the elastic layer (C), the bending moment’s point is constant at 2 m above and below the tunnel axis, whereas the shear force’s point remains constant at the buried tunnel axis’s depth and 4 m above the tunnel axis.

Why pile-supported building settled continuously after water level was stabilized during dewatering: Clues from interaction between pile and multi aquifers

Dewatering in a multi-layered aquifer-aquitard system often causes groundwater drawdowns in multiple aquifers, which together lead to obvious settlement of adjacent pile-supported building. This paper documents an in-situ pumping test conducted in a multi-aquifer system. It indicates that an adjacent pile-supported building settled continuously after water level was stabilized. To clarify the possible reasons for this phenomenon, a series of numerical models were established, validated and employed to explore the load transfer behaviour between pile and multi-aquifers during different dewatering conditions. Results indicate that the appearances of several aquitards in the multi-aquifer system significantly block the hydraulic connection between different aquifers, leading to non-synchronized developments of groundwater drawdown and pile shaft resistance at different soil layers during pit dewatering, which eventually causes the lagging settlement of the building. In practical pit dewatering in multi-aquifer system, engineers should appropriately increase the monitoring time for the deformation of adjacent pile-supported buildings for avoiding missing the maximum settlement.

Deformation behavior and damage characteristics of surface buildings induced by undercrossing of shallow large-section loess tunnels

The ground movement during the construction of shallow loess tunnels can easily cause deformation damage to surface buildings. Most the current studies focus on the damage soft soil and rock tunnels to independent buildings, and there are few studies on the case of building groups in loess areas. Using the new Xi’Yan Railway Luochuan Tunnel as a case study, we conducted on-site testing to study building settlement and crack development characteristics. Three-dimensional numerical simulations were carried out to analyze settlement, flexure deformation, and main tensile strain distribution characteristics of the buildings at different buried depths. The study determines the extent of damage resulting from differential settlement and tension cracks. The results show that construction during the upper, middle, and lower bench stages results in significant ground volume loss, leading to a ’wide and steep’ settlement pattern with a maximum settlement value of 567 mm. Building cracks exhibit positive and inverted splayed shapes, with lengths ranging from 0.5 to 6.0 m and widths between 0 to 170 mm. As buried depth increases, maximum settlement, flexure deformation, and main tensile strain of buildings also increase. The severe damage range of buildings initially increases and then stabilizes, with the maximum range caused by differential settlement and tensile cracks being 34 m and 29 m from the tunnel axis, respectively. Based on the analysis of building damage characteristics, it was determined that a combination of surface measures and measures within the tunnel should be used to control building damage caused by tunnel construction. These research findings can serve as valuable references for similar projects.

Evaluating the Stability of the Jianchuan Ancient Town with TerraSAR-X images

Abstract. Architectural heritage holds significant historical and cultural value. However, it faces substantial risks of deterioration stemming from natural aging and human activities. Traditional methods rely on manual surveys or ground-based measurements, which are time-consuming and labor-intensive, making it challenging to meet the demand for large-scale stability assessments of architectural heritage. In this study, we designed a methodology based on the analysis of differential deformation and angular distortion of buildings using InSAR line-of-sight (LOS) displacements. Then, the stability of buildings is categorized into three groups: stable, moderate, and unstable, using these stability indicators. A total of 74 TerraSAR-X images acquired from August 2017 to November 2019 in ascending orbit were used to monitor the Jianchuan Ancient Town, which has a history of over 650 years. Our evaluation reveals that among the 1891 architectures in Jianchuan Ancient Town, 1191 are rated as stable, 696 as moderate, and 4 as unstable. Time-series results indicate that one of the four unstable buildings exhibited a severe accelerating trend that requires attention. In conclusion, this methodology can enhance the capability to assess the stability of large-scale architectural heritages.

Building responses to soil removal, dewatering, and artificial recharge during deep excavation in water-rich sandy strata

In water-rich sandy strata, deep excavations necessitate dewatering within the excavation site, leading to significant groundwater drawdowns and surface subsidence behind walls, which can result in severe damage to adjacent buildings. Nonetheless, the individual impacts of soil removal and dewatering in such permeable sandy formations on building responses remain ambiguous,with scant reported protective experience in literature. This study introduces a validated three-dimensional fluid-solid coupling finite-element model to simulate the construction of an 18-19.8 m deep subway station in Nantong, China. Artificial recharge was applied to mitigate adverse effects on nearby buildings caused by drainage. The investigation explores the separate effects of soil removal, dewatering, and water recharging on the settlements of buildings with three different foundations (natural, raft, and piled footings). Additionally, the influence of post-recharging groundwater levels on building responses was scrutinized. The present findings indicate that discharging confined aquifers significantly contributes to building settlements, while artificial recharge can substantially reverse the deformations in buildings, especially those with natural and raft foundations. As excavation depth and the bearing capacity of the building foundation increase, the relative impact of soil removal on building settlements grows, whereas the influence of dewatering diminishes. Compared to enhancing foundation-bearing capacity, artificial recharge emerges as a more cost-effective strategy to safeguard pre-existing buildings near deep excavations in water-rich sandy strata, provided the post-recharging groundwater levels achieve a certain threshold.

Strain energy-based uniformity spectrum for elastic deformation control of super high-rise buildings under near-fault pulse-like earthquake excitations

To reasonably control the elastic lateral deformation of super high-rise buildings under near-fault pulse-like ground motions, inspired by a potentially close link between material utilization and normalized strain energy, a novel generalized uniformity spectrum of normalized strain energy (GUSNSE) is proposed via the nonuniform flexural-shear coupled model. With a full understanding of the characteristics of spectral shapes and the influence of shear-flexural stiffness ratios and mass-stiffness nonuniformity, the GUSNSE is fitted by artificial pulses. Utilizing the GUSNSE, a lateral stiffness estimation strategy is developed with the requirement of peak interstory drift ratios (IDRs). The feasibility and effectiveness of the proposed strategy are systematically demonstrated by comparison with not only the original lateral stiffness schemes of three significantly distinct buildings but also those designed for uniform IDRs. The accuracy of the fitted GUSNSE is also validated via the data estimated by four sets of ground motions. The GUSNSE-based strategy is promising as an efficient, reliable, and practical tool for providing lateral stiffness of super high-rise buildings in the preliminary design.

Analysis of the influence of external factors on the deformation of high-rise buildings in the process of their construction and operation

During the construction and operation of high-rise buildings, their vertical axis changes its position in space. The greater the height of the structure, the greater the amplitude of oscillations. This causes problems of geodetic construction support and the need to monitor deformations during the operation of high-rise structures. In real conditions, part of the structures will be in the shade and their temperature will be lower than the structures that will be under the influence of solar radiation, the temperature of which will be much higher. Thus, the building will deform as a result of uneven thermal expansion, that is, it will bend. From DBN B.1.3-2:2010 "Geodesic works in construction". Also, during the geodetic provision of the construction and operation of high-rise buildings, changes in the temperature regime of building structures should be taken into account in connection with significant absolute values of changes in the geometric dimensions of the building as a result of thermal expansion, which significantly exceed the accuracy regulated by the regulatory document. The article examines and analyzes the influence of external forces on changes in the geometry of high-rise structures and focuses attention on solving the scientific problem of geodetic support for the construction and operation of modern high-rise structures under dynamic loads.

Foreign Experience Review on Engineering Protection of Seashores and Hillslopes

Introduction. During design, construction and operation of buildings and structures in the coastal areas there arises a serious problem of engineering protection of coasts and hillslopes from the dangerous geological processes, which include the coastal erosion, underflooding of territories, hillslope erosion, gravitational (slope) processes, such as intensification of landslides, etc. These processes often result in significant economic damage usually related to the non-recoverable loss of valuable coastal territories, deformation of buildings and structures, damage and destruction of the objects of transport and engineering infrastructure. In this regard, the study of the advanced foreign experience in engineering protection of the coastal areas and the evaluation of the possibility of it to be implemented in Russia is a relevant scientific and engineering task.Materials and methods. To prepare the review, the following data was used: field observation data with photographic evidences of the objects of engineering protection of seashores and hillslopes obtained by the authors during a business trip to the People's Republic of China (PRC) in October–November 2023; study and analysis of literature sources in the subject area, including the methods and technologies implemented in the Netherlands, Japan, the USA, Great Britain, Italy; summary and systematisation of the coastal protection methods for further development of their classification and evaluation of the possibility of implementing thereof in the Russian Federation.Research results. The main principles of design, the advanced methods and technologies of coastal protection used in China have been defined. They include: construction of the multi-level protective structures, such as the multiple-row breakwaters of special shape in combination with the stepped retaining walls, the vertical walls consisting of the driven piles, anchoring and spray-concrete covering of the slopes in combination with the metal meshes; terracing in combination with the retaining reinforced concrete (horizontal and vertical) crossbeams; the sloping wave-absorbing reinforced concrete surfaces; the meshy structures and fences combating the Aeolian processes, etc.The main methods used in the Netherlands, Japan, the USA and Italy for comprehensive protection of the large territories have been defined. Such as: the network of dams, weirs, wave breakers, coast paving, regulation of the flows by water locks and barriers, creation of the artificial protective islands; artificial replenishment with sand; creation of the green spaces along the coast; forming the dunes — natural or artificial hills of sand or pebbles located along the coast; creation of the concrete structures, stone jetties, floating constructions and even artificial reefs.The importance of management was emphasised, including the early warning systems for storms and tsunamis, weather and marine condition monitoring systems, as well as dissemination of the warning messages and evacuation plans among the population in the areas of potential threat.Discussion and conclusion. Based on the results of the review, the main conclusions were formulated. The recommendations were given on the possible ways of improving the coastal protection of the Caucasian Black Sea Coast and other coastal areas of the Russian Federation based on the advanced foreign experience.

GEODETIC MONITORING OF DEFORMATIONS OF BEARING REINFORCED CONCRETE STRUCTURES OF AN UNDERGROUND MULTI-FUNCTIONAL PUBLIC CENTER

The article highlights the stages of carrying out measurement and survey work of an underground multifunctional public center to assess the technical condition of the load-bearing structural elements of block 1 and the entrance group in order to carry out reconstruction on the above-ground part of the building. The reconstruction consisted of installing metal structures on the eastern and western sides of the dome and a metal canopy over the entrance group. As a result of a technical examination and geodetic observations, cracks with an opening width of 0.5 mm and significant deflections in the floor slabs and crossbars at the upper and lower levels were identified in the load-bearing structures. To ensure safe operation and timely detection of dangerous values of deformation of a unique building with an increased class of responsibility, an effective method of geodetic monitoring of deflections of reinforced concrete floor slabs and crossbars and recommendations for their strengthening, taking into account the location of the construction site at the intersection of zones of influence of several tectonic faults, are proposed. Geodetic observations of deformation processes were carried out. Based on the results of the measurements, it was decided to strengthen the reinforced concrete structures by gluing fiber-reinforced composite materials to the lower part of the floor slabs. A comparative analysis of the obtained quantitative parameters of shifts of load-bearing structures makes it possible to assess the technical condition of an underground building and its individual structures before and after strengthening measures.

Rapid full-field deformation measurements of tall buildings using UAV videos and deep learning

Full-field deformation of tall buildings is informative and imperative for structural health condition assessments. This study explores the feasibility of using videos recorded by an unmanned aerial vehicle (UAV) to measure the vibration profiles of tall buildings with the aid of deep neural networks. First, a Transformer network with a self-attention mechanism is used, and its outcome is employed for the homography transformation to minimize the drifting problems induced by the UAV. Second, a boundary-aware salient object detection network is adopted to extract the boundary of the buildings in the stabilized videos for further full-field deformation measurements. The accuracy of the proposed method is experimentally validated using a wood frame structure under harmonic excitations. Under a measuring distance of approximately 4.2 m, the proposed method achieves averages of root-mean-square-errors (RMSEs) for the displacement and rotation measurements of 2.13 mm and 1.74 × 10−3 rad, respectively, as compared to that determined by an infrared light tracking system. The study further analyzes the field-test data recorded from the vibration of a 247-m tower. Under a measuring distance of about 55 m, the proposed method is comparable to the vibration measurement at a specific story and estimates the full-field deformation within the region of interest. Overall, the proposed method with rapid UAV deployment is feasible and accurate for monitoring the full-field deformation using the UAV-recorded videos.

Delayed deformation of confinement buildings: 30‐Year in situ measured data and prediction with the next‐generation Eurocode‐2

AbstractBiaxially prestressed large concrete structures of the confinement building in nuclear power plants (NPPs) should meet the safety requirement for the extension of the service time. Long‐term delayed strains of concrete are one of the key factors determining the safety factor in these structures. This article presents 30‐year long in situ measurement results of strain evolution of confinement buildings in four different NPPs. The delayed strains are predicted at a material level using the next‐generation Eurocode‐2, and the influence of temperature as proposed by the fib model code 2010, making use of delayed strain characteristics of the corresponding concrete from a previous study. We found that the default law given in Eurocode underestimates the delayed strain. However, with the possibility of adjusting the shrinkage and creep laws, the prediction results fit with a good accuracy for the in situ measurement.

Study of the Mechanical Behavior of Retaining Structures and Adjacent Buildings during the Excavation of Deep and Long Pits

Excavation of deep and long pits can cause strata deformation and settlement of adjacent buildings. The excavation of a deep foundation pit of a nearby building in Zhengzhou City, China, is taken as the research object. The foundation of the foundation pit is an independent foundation under the column, the depth of the foundation pit is 24.5∼26.3 m, and the support form of an underground continuous wall and four internal supports is adopted. The stress and deformation characteristics of retaining structures during the construction of deep and long pits and their impact on the deformation of nearby buildings were studied through on‐site monitoring and finite element simulation. The analysis focuses on the effects of different excavation stages on adjacent structures, with the main conclusions as follows. After excavation, the underground continuous wall far from the building undergoes a “rotating‐kick” displacement, while the underground continuous wall on the side near the building only shows a “kick” displacement. Adjacent buildings have little influence on the distribution of shear force and bending moment of the underground continuous wall of the foundation pit. The first horizontal strut experiences pressure, gradually shifting to tension as excavation continues, with the maximum stress reaching 3.6 × 103 kN. The second, third, and fourth horizontal struts mainly bear compressive forces, increasing with the depth of the struts. The building primarily undergoes settlement in the early stages of deep and long pit excavation. As the excavation progresses, the building points near the pit begin to bulge, but the building corners far from the pit continue to show settlement. During the excavation of the deep and long pit, the differential settlement of the long side of the nearby building first decreases and then increases, and the differential settlement of the short side changes from a slight decrease to a significant increase. The settlement evolution of the building is as follows: overall settlement ⟶ overall uplift ⟶ uplift of the side of the building near the pit ⟶ outward tilting away from the pit. The findings may provide references for designing, constructing, and operating deep and large foundation pits.

Опасность оползневой деятельности в Моздокском районе Республики Северная Осетия – Алания

The object of the study is landslide activity in the Mozdok administrative region of the Republic of North Ossetia-Alania. The work examines the results of systematization and analysis of various sources containing information about the activity and danger of landslide processes in this area in the 21st century. The conditions, causes, activity and danger of landslide activations in the region are characterized. It is noted that the activity of landslide processes in the study area is mainly due to natural factors, however, recently the emergence of new landslide forms and the activation of old ones most often occur under technogenic influence. Landslide activity in the region is observed on the ledge of the right bank alluvial-accumulative terrace of the river. Terek, where most of the settlements of the region are located, as well as the northern slope of the Tersky ridge and in the area of the watershed ridge of the Sunzhensky ridge. The most significant activation of landslide processes (causing deformation of residential buildings and roadways of streets) was observed in the villages of Maly Malgobek, Predgornoye and Sukhotskoye. Since 2021, after the reconstruction of the Zilga – Mozdok highway, significant landslide deformations and destruction of the roadway have been observed on the section of the road between the villages of Khurikau (Mozdok district) and Old Batako (Right Bank district). The article provides information about the activity of landslide activity and the scale of deformations and destruction of residential and transport infrastructure that occurred in the area. Analysis of the socio-economic consequences of the landslide activations shows a significant degree of their danger to the life of the population in the Mozdok region.

Deformation Monitoring of High‐Rise Building Clusters: Acquiring Deformation Coefficients by Combining Satellite Imagery and Persistent Scatterer Interferometry

Persistent Scatterer Interferometry (PSI) is a remote sensing measurement technology based on electromagnetic waves, capable of simultaneously monitoring deformations in large urban building complexes with millimeter‐level precision. However, relying solely on the line of sight (LOS) deformation sequence based on a specific permanent scatterer cannot accurately analyze building deformations, particularly in cases where high‐rise buildings may simultaneously experience various deformation components such as temperature‐induced deformation, shrinkage, creep, and tilting. To accurately identify the deformation states of high‐rise buildings, the paper begins by systematically summarizing three typical deformation patterns from the unique perspective of synthetic aperture radar (SAR) satellites. These patterns include Pattern I, characterized by temperature‐induced deformation alone, and Pattern II and Pattern III, which involve a combination of deformation in different directions relative to the SAR satellite in addition to temperature‐induced deformation. To accurately monitor the LOS deformation of high‐rise buildings, the paper introduces the concept of acquiring the evolutionary trends of temperature‐related deformation coefficients and proposes a methodology for recognizing and quantifying deformation in high‐rise buildings. Subsequently, this study utilized freely available Sentinel‐1 satellite data to observe the deformation of nine high‐rise buildings in Changsha, China. The research findings indicate that the thermal expansion coefficients of most high‐rise buildings fall within the range of 6 ∼ 12 × 10−6/°C. High‐rise buildings that have been constructed for more than ten years almost no longer experience significant shrinkage or creep, while new constructions may exhibit an initial shrinkage and creep of up to 1.2 × 10−4 mm/mm. Additionally, the study results demonstrate that super‐tall buildings may exhibit centimeter‐scale lateral deformations at their tops due to uneven shrinkage. Findings from the study indicate that the proposed method can achieve cost‐effective and sustainable deformation monitoring of high‐rise building clusters within a large urban area.

The influence of the parameters of engineering protective structures on the effectiveness of their use in densely built-up territory

A study of the influence of application of an engineering protective screen made of small-diameter driven piles on the existing building deformations, caused by the arrangement of the pit fence made of bored piles, was carried out. The study was carried out with the help of numerical modeling using the method of finite elements, which allowed to display the work of the system "soil base - engineering protective structures - the foundation of the existing building" with different parameters of the protective screen. The influence of the following parameters is shown:
 1) the depth of laying the protective screen L in relation to the depth of the compressible soil zone (Hst).
 2) the position of the protective screen between the retaining structures of the pit and the existing building.
 3) rigidity of the screen – the ratio of the step to the diameter of the piles of the engineering protective screen.
 4) the distance between the existing building and the pit in relation to the depth of the enclosing structures of the pit of the new construction.
 The tasks were modeled in a spatial arrangement with the task of the system "soil base - enclosing constructions of the pit - protective screen - foundations of the existing building". The soil environment was modeled using the Hardening Soil Model. The calculation was carried out in stages.
 The variation of the parameters of the protective screen was carried out for the historical building, which in most cases was made according to a rigid wall construction scheme with strip foundations.
 The foundation depth is 1.2 - 3.0 m and the foundation width is 1-2 m. The average pressure under the foundation is 150-250 kPa.
 The rational depth of the foundation and the position of the protective screen between the existing building and the pit of the new construction were established.
 The area of effective application of the protective screen was revealed, depending on the distance between the building and the pit fence.
 The effective stiffness is established depending on the change in the relative distance between the poles of the protective screen.