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This study investigates the underlying causes of pier displacement and cracking in a highway link bridge. The initial geological assessment ruled out slope instability as a contributing factor to pier movement. Subsequently, a comprehensive analysis, integrating in situ soil investigation and finite element modeling, was conducted to evaluate the influence of additional fill loads on the piers. The findings reveal that the additional filled soil loads were the primary driver of pier tilting and lateral displacement, leading to a significant risk of cracking, particularly in the mid- of the piers. Following the removal of the filled soil, visual inspection of the piers confirmed the development of circumferential cracks on the columns of Pier 7, with the crack distribution closely aligning with the high-risk zones predicted by the finite element analysis. To address the observed damage and residual displacement, a reinforcement strategy combining column strengthening and alignment correction was proposed and validated through load-bearing capacity calculations. This study not only provides a scientific basis for analyzing the causes of accidents and bridge reinforcement but, more importantly, it provides a systematic method for analyzing the impact of additional filled soil loads on bridge piers, offering guidance for accident analysis and risk assessment in similar engineering projects.

期刊论文 2025-06-02 DOI: 10.3390/buildings15111929

Vertical-inclined alternating composite steel pipe pile(VIACP) is a new green foundation pit support technology. A numerical experimental study on the mechanical properties of vertical-inclined combination piles with different pile inclination angles and lengths was carried out with a foundation pit in Longli County, Guizhou Province, as the research object. Results demonstrate that the VIACP reduces maximum deformation by 57.8% (20.07 mm) compared to traditional cantilever piles (47.57 mm), aligning closely with field monitoring data (16.94 mm). The parametric study shows that the maximum horizontal displacement of the pile decreases and then increases as the inclination angle (5 degrees-30 degrees) increases, with the minimum displacement (20.07 mm) at 20 degrees, which is the optimum angle. Increasing pile lengths lead to progressively reduced displacements followed by stabilization while alternating long-short pile configurations exhibit synergistic effects. Mechanically, axial forces and lateral friction resistance show negative correlations with inclination angles, while bending moments adopt an S-shaped distribution along pile depth with minimal sensitivity to angle variations. Mechanism analysis highlights that the inclined piles in the structure have a pull-anchor effect, the soil between the piles together has a gravity effect, and the alternating arrangement of piles has a spatial structure effect. The three major effects increase the stiffness and stability of the support structure, which is conducive to the deformation control of the foundation pit. The research results will provide a theoretical basis for the popularization and application of the structure.

期刊论文 2025-03-06 DOI: 10.1080/15376494.2025.2476206 ISSN: 1537-6494

Two disastrous earthquakes, named Pazarc & imath;k (Mw7.8) and Ekin & ouml;z & uuml; (Mw7.6), occurred on February 6, 2023 in the southeast part of T & uuml;rkiye and were collectively named Kahramanmara & scedil; earthquakes. These seismic events were caused by a left lateral strike-slip faults, and resulted in significant loss of life, severe damage to infrastructures and buildings, and geotechnical damages such as mainly large-scale slope failures, rockfalls, and ground liquefaction. The main goal of this study is to assess the extend and impact of widespread ground liquefaction, particularly on built environment. Additionally, the ranges of amount of settlement and tilting of buildings due to ground liquefaction were briefly discussed and liquefaction caused by Kahramanmara & scedil; earthquakes were compared with those others occurred in T & uuml;rkiye. The site observations indicated that except a village, a short of a highway, a few bridges and two settlements, widespread liquefaction was mainly observed in agricultural non-urbanized fields. The maximum amount of settlement at some liquefaction locations reached up to 2 m and high-raise buildings tilted 7-8 degrees from the vertical reaching up about 20 degrees. Observations indicated that single-storey and two-storeys buildings with a basement to a certain depth, a lower center of gravity and raft foundation should be considered suitable on soils susceptible to liquefaction in earthquake-prone regions without taking any counter-measures against ground liquefaction. Mass movements along the shoreline of the G & ouml;lba & scedil;& imath; Lake were unlikely to be caused by lateral spreading resulting from ground liquefaction and they were rather due to planar sliding along a weak layer dipping towards the lake with progressive failure.

期刊论文 2024-11-01 DOI: 10.1007/s10064-024-03946-w ISSN: 1435-9529

External factors affecting the processes of sprinkler irrigation water flow generation, flight, and landing have not been thoroughly considered in existing ballistic models. This result indicates that ballistic models with better prediction effects under specific conditions are not sufficient for extension to multi-factor coupled scenarios in large-scale farmlands. Therefore, wind, evaporation, surface slope, and tilted sprinkler riser factors were comprehensively considered in this study. Differential equations for jet and droplet motion under the influence of wind, differential equations of droplet evaporation, sprinkler riser deflection angle matrix, and surface slope angle matrix were constructed to establish a droplet distribution model for sprinkler irrigation considering multifactor coupling using MATLAB 2018a software. The results showed that, under different working conditions, the data points of the droplet landing diameter, velocity, and angle were distributed near the 1:1 line. The Nash efficiency coefficients (NSE) for the droplet landing diameter, velocity, and angle varied from 0.821 to 0.932, 0.616 to 0.931, and 0.770 to 0.911, respectively. The increase in slope resulted in droplets with diameters larger than 4.63 mm concentrating on the land in the reverse slope direction. When the ambient temperature increases from 10 to 45 degrees C and the total evaporation rate increases from 0.45 to 4.37%, the larger droplets have a larger area of contact with the air, and the higher the temperature, the greater the energy loss to the larger droplet diameters. The higher the wind speed, the more droplets in the downwind direction fall to the ground at a smaller landing angle, which can easily increase the risk of soil shear damage. If the sprinkler riser was tilted east, the droplets on both the east and west sides tended to be distributed centrally; the maximum droplet landing velocity occurred on the east side (tilted side), and the maximum droplet landing angle occurred on the west side. This study considers various factors that may affect the motion of sprinkler irrigation water flow, extends the application scenarios of the theoretical model, and improves the applicability of the theoretical model for sprinkler irrigation droplet motion in more complex and practical agricultural environments.

期刊论文 2024-10-01 DOI: 10.1016/j.compag.2024.109352 ISSN: 0168-1699

Geofoam, when substituting soil, reduces lateral static load due to its lightweight and compressible nature. The alignment and the orientation of the geofoam greatly affect the deflection of the wall. This paper investigates the influence of different geofoam orientations on the load-deformation characteristics of the reinforced retaining wall. Static load tests were performed when sand or geomaterial prepared from sand, bottom ash, and plastic strips were used as a backfill material. Different orientations were explored when geofoam of densities 11D, 16D, and 34D where D is the density of geofoam were laid in different directions. A layer of compressible inclusion with a thickness of 10 cm was laid either in the vertical direction alone or in both vertical and horizontal directions. Another option was to use a 10-cm-thick geofoam laid in the vertical direction and geofoam strips of thickness 2, 3, or 5 cm laid in layers. The reinforcement effect was analyzed using bearing capacity ratio, vertical displacement reduction, and wall deflection reduction. Results indicated that higher-density geofoam is more efficient in reducing settlement values and increasing bearing capacity. Lower-density geofoam excelled in wall deflection reduction. The most substantial improvements were observed for 10-cm-thick 16D geofoam laid in the vertical direction, accompanied by 5-cm-thick strips laid in three layers in the horizontal direction. This combination reduced the settlement and wall deflection to 78.23% and 98.81%, respectively.

期刊论文 2024-10-01 DOI: 10.1007/s40515-024-00401-x ISSN: 2196-7202

Although soil stabilization with cement and lime is widely used to overcome the low shear strength of soft clay, which can cause severe damage to the infrastructures founded on such soils, such binders have severe impacts on the environment in terms of increasing emissions of carbon dioxide and the consumption of energy. Therefore, it is necessary to investigate soil improvement using sustainable materials such as byproducts or natural resources as alternatives to conventional binders-cement and lime. In this study, the combination of cement kiln dust as a byproduct and zeolite was used to produce an alkali-activated matrix. The results showed that the strength increased from 124 kPa for the untreated clay to 572 kPa for clay treated with 30% activated stabilizer agent (activated cement kiln dust). Moreover, incorporating zeolite as a partial replacement of the activated cement kiln dust increased the strength drastically to 960 and 2530 kPa for zeolite ratios of 0.1 and 0.6, respectively, which then decreased sharply to 1167 and 800 kPa with further increasing zeolite/pr to 0.8 and 1.0, respectively. The soil that was improved with the activated stabilizer agents was tested under footings subjected to eccentric loading. The results of large-scale loading tests showed clear improvements in terms of increasing the bearing capacity and decreasing the tilt of the footings. Also, a reduction occurred due to the eccentricity decreasing as a result of increasing the thickness of the treated soil layer beneath the footing.

期刊论文 2024-09-01 DOI: 10.3390/infrastructures9090160

The Kahramanmaras, seismic sequence of February 6th, 2023, caused extreme damage and a significant number of casualties across a large region of Turkey and Syria. The paper reports on the survey activities carried out by the authors in the city of Golbas,& imath;, where extensive liquefaction took place. The damage to the built environment caused by liquefaction differs from that caused by typical inertial seismic actions, with quasi-rigid body displacement mechanisms, resulting in extreme settlements, tilts, and, in some cases, complete overturning. After a brief introduction to the geological features of the Golbas,& imath; area and a discussion of the seismic effects on the area, the paper reports and comments on the damage observed in one part of the city and provides some statistical interpretations.

期刊论文 2024-08-01 DOI: 10.1016/j.enggeo.2024.107633 ISSN: 0013-7952

A large steel water tank installed at a coal power plant in Cilegon, West Java, Indonesia, faced stability and strength concerns due to significant tilting observed during a water load test. As a precautionary measure, the tank was emptied, and a thorough assessment was initiated to evaluate its fitness for purpose and to determine the strength and stability of both the tank and its foundation for long-term use. The site investigation identified uneven settlement and tilting of the foundation. To conduct a root cause analysis, finite element analysis was performed, with soil properties calibrated based on measured settlement. The mapped deformation of the tank's base was compared to industry standards such as API 653, EEMUA 159, and PIP STE02030. The analysis revealed that the failure resulted from an error in calculating the strength of the base soil during the design phase. Fortunately, the tank itself did not sustain significant damage, experiencing only rigid body displacement with minimal out-of-plane deformation, rendering repairs unnecessary. A proposed retrofit solution to enhance the strength of the soil beneath the tank is to implement soil improvement by concrete jet grouting. Once the soil characteristics have been improved, a comprehensive finite element analysis confirmed that both the steel water tank and the reinforced soil surrounding it will remain within acceptable stress and deformation levels for both short-term and long-term conditions. Field measurements further validate that the application of concrete jet grouting has effectively reduced the settlement potential of the tank.

期刊论文 2024-02-01 DOI: 10.21660/2024.114.g13402 ISSN: 2186-2982

In recent years, many housing retaining walls have been damaged or even collapsed by earthquakes in Japan. Among them, the damage to dry masonry retaining walls was prominent. Although there are reinforcement methods for retaining walls such as the earth nailing or the ground anchors, which are not suitable for housing retaining walls due to inadequate construction space. Other reinforcement method such as the root piles, on the other hand, straight piles and tilting piles are installed into sloping ground from the top of slope bank vertically so as easier to construct in narrow residential areas, hence widely applicable for housing retaining walls. But the problem of root piles is that the construction cost tends to be high for individual houses since many straight piles and tilting piles are used. From this background, we propose a reinforcement method in which only use tilting piles and connect the top of them to the top of the existing retaining wall to reduce construction cost by decreasing the number of reinforcing materials. This report aims to confirm how a distance between a retaining wall and a reinforcing material affects on the earthquake resistance by conducting centrifugal tilting tests using dry masonry retaining walls. The results show that connecting the top of the retaining wall to the top of the reinforcement allows the retaining wall retain higher soil pressure and the influence of reinforcement becomes increasing.

期刊论文 2024-01-01 DOI: 10.1007/978-981-99-9223-2_7 ISSN: 2366-2557
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