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西南地区某铁路站场高填方土压力实测分析
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作者 吴浩 肖玉林 +4 位作者 张春龙 邹华 秦舒桢 李国峰 雷胜友 《山西建筑》 2026年第2期129-133,共5页
为了探究大临铁路站场的高填方结构中土压力的变化规律,在高填方中布设了多排土压力盒,同时在高填方底部的涵洞左右肩处各布设了一排土压力盒,经过两年多监测,发现填土中竖向土压力随填土高度的增加而增加,随距填土体顶面距离的增加呈... 为了探究大临铁路站场的高填方结构中土压力的变化规律,在高填方中布设了多排土压力盒,同时在高填方底部的涵洞左右肩处各布设了一排土压力盒,经过两年多监测,发现填土中竖向土压力随填土高度的增加而增加,随距填土体顶面距离的增加呈现先增加后减少的态势,总体符合梅耶霍夫准则,反映出土拱效应。沿填土体的横截面方向比较,发现在填土的初期阶段,竖向土压力沿横断面分布相对均匀,第一层土压力随着填土体高度的增加而增加,表现出左边大、右边小的变化规律,高填方竣工后,横断面上土压力数值还在调整变化,整个曲线在横向呈S状分布,与第一层土压力相比,第二层以及后续填土层的竖向土压力虽然也随填土体高度的增加而增加,但在横向则呈R状分布。涵洞左肩处土压力随填土高度的增加而增加,表现为左端的土压力最大,右端土压力最小,沿涵洞轴线方向呈波浪式衰减,填土竣工后,土压力稳定,呈多峰的马鞍型分布。涵洞右肩土处的压力分布稍有不同,在洞轴线中部土压力分布相对比较均匀。 展开更多
关键词 竖向土压力 土拱效应 横断面 填土体 涵洞肩部
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涵洞段沥青路面沉陷与开裂问题分析及加固措施研究
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作者 杜劲海 《价值工程》 2026年第2期97-99,共3页
涵洞段作为公路结构中的薄弱环节,常因基础沉降不均、结构设计不合理或施工质量控制不严等因素,导致沥青路面出现沉陷与开裂等病害,影响道路的使用性能和行车安全。本文以典型涵洞段路面病害为研究对象,结合现场调查与结构分析,系统探... 涵洞段作为公路结构中的薄弱环节,常因基础沉降不均、结构设计不合理或施工质量控制不严等因素,导致沥青路面出现沉陷与开裂等病害,影响道路的使用性能和行车安全。本文以典型涵洞段路面病害为研究对象,结合现场调查与结构分析,系统探讨其沉陷与开裂的主要成因,指出涵洞沥青路面沉降、裂缝分类等是造成病害的关键因素。在此基础上,提出包括优化涵洞接缝设计、注浆加固软弱地基、3DCG工法调平处治等加固措施。通过加固措施的实施,可为类似道路结构病害的预防与治理提供参考依据。 展开更多
关键词 涵洞段沥青路面 沉陷 开裂问题 加固措施
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The effects of water flow and temperature on thermal regime around a culvert built on permafrost 被引量:3
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作者 Loriane Périer Guy Doré +3 位作者 C.R.Burn Loriane Perier Guy Dore C. R. Bum 《Research in Cold and Arid Regions》 CSCD 2014年第5期415-422,共8页
Temperature and water flow through a culvert beneath the Alaska Highway near Beaver Creek,Yukon,were measured at hourly intervals between June and October 2013.These data were used to simulate the effect of the culver... Temperature and water flow through a culvert beneath the Alaska Highway near Beaver Creek,Yukon,were measured at hourly intervals between June and October 2013.These data were used to simulate the effect of the culvert on the thermal regime of the road embankment and subjacent permafrost.A 2-D thermal model of the embankment and permafrost was developed with TEMP/W and calibrated using field observations.Empirical relations were obtained between water temperatures at the entrance to the culvert,flow into the culvert,and water temperatures inside the structure.Water temperatures at the entrance and inside the culvert had a linear relation,while water temperatures inside the culvert and water flow were associated by a logarithmic relation.A multiple linear regression was used to summarize these relations.From this relationship,changes in the flow rate and water temperatures at the entrance of the culvert were simulated to obtain predicted water temperatures in the culvert.The temperatures in the culvert were used in the thermal model to determine their effects on the ground thermal regime near the culvert.Variation of ±10% in water flow rate had no impact on the thermal regime underneath the culvert.Variation of water temperature at the entrance of the culvert had a noticeable influence on the thermal regime.A final simulation was conducted without insulation beneath the culvert.The thaw depth was 30 cm with insulation,and 120 cm without insulation,illustrating the importance of insulation to the ground thermal regime. 展开更多
关键词 culvert thermal regime water flow water temperature MODELING PERMAFROST
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Study on dynamic response of embedded long span corrugated steel culverts using scaled model shaking table tests and numerical analyses 被引量:12
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作者 车爱兰 IWATATE Takahiro 葛修润 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第3期430-435,共6页
A series of scaled-model shaking table tests and its simulation analyses using dynamic finite element method were performed to clarify the dynamic behaviors and the seismic stability of embedded corrugated steel culve... A series of scaled-model shaking table tests and its simulation analyses using dynamic finite element method were performed to clarify the dynamic behaviors and the seismic stability of embedded corrugated steel culverts due to strong earth-quakes like the 1995 Hyogoken-nanbu earthquake. The dynamic strains of the embedded culvert models and the seismic soil pressure acting on the models due to sinusoidal and random strong motions were investigated. This study verified that the cor-rugated culvert model was subjected to dynamic horizontal forces (lateral seismic soil pressure) from the surrounding ground, which caused the large bending strains on the structure; and that the structures do not exceed the allowable plastic deformation and do not collapse completely during strong earthquake like Hyogoken-nanbu earthquake. The results obtained are useful for design and construction of embedded long span corrugated steel culverts in seismic regions. 展开更多
关键词 Embedded corrugated steel culverts Shaking table tests Hyogoken-nanbu earthquake Dynamic analyses
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Centrifugal model test and numerical simulation of vertical earth pressure on soft foundation box culvert 被引量:3
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作者 张军辉 姚永胜 +1 位作者 郑健龙 张涛 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第9期3556-3563,共8页
To obtain the vertical earth pressure on a soft foundation box culvert and investigate the interaction of the soil-culvert-foundation system, both a centrifugal model test and a numerical simulation were conducted and... To obtain the vertical earth pressure on a soft foundation box culvert and investigate the interaction of the soil-culvert-foundation system, both a centrifugal model test and a numerical simulation were conducted and the comparisons with the current methods to determine the load on a culvert were completed. The results of the model test and numerical analysis are in satisfactory agreement, which shows that the direction of the shear stress between the culvert and the adjacent embankment depends on the differential settlement between them. A vertical earth pressure concentration appears on the culvert with a rigid piles foundation because of a downward shear stress. The ratio of the load on a soft foundation culvert and the overburden pressure above the culvert raises first and then decreases as the backfill height increases. In order to reduce the load on a culvert, it is suggested to limit the stiffness difference of the foundations under the culvert and embankment and to use a light backfill over the culvert. 展开更多
关键词 box culvert vertical earth pressure soft foundation centrifugal model test
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The Collapse of Culverts-Arch in Several Cities around the World, Technical Arguments for Their Maintenance and a Legal Proposal for Prohibiting Their Construction in Mexico 被引量:1
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作者 Martín D. Mundo Molina José L. Pérez Díaz +1 位作者 Daniel Hernández Cruz Eber Godínez Domínguez 《Journal of Water Resource and Protection》 2019年第12期1489-1502,共14页
Construction underground pipes and underground culvertsarch (UCA) in order to transport the flow natural rivers and city’s sewage at the same time, is a practice that should be prohibited by the Mexico National Water... Construction underground pipes and underground culvertsarch (UCA) in order to transport the flow natural rivers and city’s sewage at the same time, is a practice that should be prohibited by the Mexico National Water Law (NWL). When UCA collapse, it causes severe damage to surrounding infrastructure, public and private property, and puts citizens’ lives at risk. This work presents some examples of UCA collapse incidents in several cities around the world, emphasizes how important preventive maintenance of these structures is, highlights the need to classify risk areas, and stresses the need to formulate norms and civil defense plans as article 83 of the NWL suggests. We also propose an addition to Fraction I, article 100 of the National Water Law, to protect the animal and plant life of its banks and safety of their natural runoff. 展开更多
关键词 culvert National Water Law COLLAPSE
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Frost heave analysis of ballasted track above box culvert and its influence on train vibration 被引量:1
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作者 Bin Luo Hao Lai +1 位作者 Tatsuya Ishikawa Tetsuya Tokoro 《Research in Cold and Arid Regions》 CSCD 2017年第3期229-235,共7页
The uneven frost heave of frost-susceptible subgrade soil causes track irregularity,which highly enhances train vibration and affects the comfort and safety of railway transportation.This paper presents a coupled ther... The uneven frost heave of frost-susceptible subgrade soil causes track irregularity,which highly enhances train vibration and affects the comfort and safety of railway transportation.This paper presents a coupled thermo-hydro-mechanical(THM)analysis for the freezing behavior of railway located above a box culvert.The vertical acceleration of the vehicle,an indicator of riding comfort,is predicted through a vehicle dynamic model.The results reveal that the existence of a box culvert changes the subgrade thermal pattern,leading to a deeper frost penetration depth.The frost heave amount above the box culvert is larger than the adjacent section,resulting in uneven track structure upheave and track irregularity.This frostinduced track irregularity highly affects train vibration. 展开更多
关键词 railway box culvert coupled ANALYSIS uneven FROST HEAVE track IRREGULARITY train vibration
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Ground penetrating radar applied to subsurface culverts 被引量:1
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作者 Tess Luo Song Zhu +2 位作者 Yiliminuer Yikeremu Jiasong Zhu John van Genderen 《Geo-Spatial Information Science》 CSCD 2024年第6期2092-2108,共17页
The failures of culverts can result in water and soil loss in the surrounding subsurface,leading to collapses.In densely constructed urban areas,buried culverts are inaccessible and invisible,making Ground Penetrating... The failures of culverts can result in water and soil loss in the surrounding subsurface,leading to collapses.In densely constructed urban areas,buried culverts are inaccessible and invisible,making Ground Penetrating Radar(GPR)inspection a widely adopted nondestructive and efficient method.Previous research has employed artificial intelligence to automate GPR interpretation by identifying special radargram textures,but the irregular GPR responses of degraded subsurface soils present a challenge.Therefore,this study proposes a method for preliminary diagnosing large-scale culverts based on GPR wave attributes.The method comprises three parts:(1)evaluating soil compactness by estimating the tortuosity of GPR responses at the culvert top;(2)investigating soil moisture using the attenuation rate of GPR responses;and(3)overlaying the results of the incompact and moist soils to pinpoint potential degradations.Two long-distance culverts were inspected and diagnosed using the proposed method,and three abnormal sections were identified and confirmed by excavation evaluation.The case studies indicate that the proposed method can quickly provide reference for further in-depth investigation,thereby improving GPR survey efficiency and reducing workload by narrowing the investigation scope.Consequently,this study can facilitate large-scale GPR culvert surveys and further safeguard the water system. 展开更多
关键词 culvert diagnosis Ground Penetrating Radar(GPR) wave attribute soil degradation
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Relative Depth Effects on Corrugated Culvert Roughness
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作者 Jonathan Scott Toews Shawn Paul Clark 《Journal of Water Resource and Protection》 2012年第10期838-841,共4页
Fish passage is important to the overall health of an ecosystem. Therefore, it is important to be able to accurately predict flow conditions within a stream crossing for high and low flow periods. This paper evaluates... Fish passage is important to the overall health of an ecosystem. Therefore, it is important to be able to accurately predict flow conditions within a stream crossing for high and low flow periods. This paper evaluates the effect of relative water depth on the hydraulic roughness of culverts at low discharge. A 21 m long, 0.8 m diameter corrugated steel pipe with 0.068 × 0.013 m annular corrugations was used. For relative depths below 0.5, Manning’s n was found to increase with decreasing relative depth. An equation was developed to predict relative depths below 0.5 within a corrugated steel pipe based on the corrugation height, slope and culvert diameter. While Manning’s equation does perform reasonably well, the percent difference from the measured to predicted water levels warrants the use of an additional prediction method at low flows. 展开更多
关键词 culvertS FISH PASSAGE Low FLOWS ROUGHNESS Manning’s Equation
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Origin of Erosion and Hydraulic Problems of the San Roque Underground Arched Culvert Channel and Its Relationship with the Maximum Flow Rate and the Maximum Permissible Velocity
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作者 Martín Mundo-Molina Daniel Hernández-Cruz 《Journal of Water Resource and Protection》 2020年第12期1123-1139,共17页
This work presents the hydrologic estimations of the hydraulic underground arched culvert channel (UACC) in Sabinal Basin, Chiapas, México and the hydrological problems associated with it, such as the erosion phe... This work presents the hydrologic estimations of the hydraulic underground arched culvert channel (UACC) in Sabinal Basin, Chiapas, México and the hydrological problems associated with it, such as the erosion phenomenon and abrasion cavity formation in it. On the other hand, the maximum flows that the UACC could transport were analyzed, concluding that it no longer has the hydraulic capacity to transport the flow rate associated to return periods equal to or greater than five years and that maximum permissible velocity UACC’s bottom is 3 m/s. 展开更多
关键词 Collapse Underground Arched culvert Channel Maximum Flow Rate Maximum Permissible Water Velocity Open Channel Bottom Erosion
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Finite Element Analysis Study of Box Culvert Jacking-Out Construction under Existing Railway Line
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作者 Senqiang Lu Yating Sun Qiaowen Hu 《Engineering(科研)》 CAS 2023年第3期196-206,共11页
To shorten the existing box culvert demolition construction period and ensure the normal operation of the railway, the jacking-out construction method was adopted. The ABAQUS finite element software was used to establ... To shorten the existing box culvert demolition construction period and ensure the normal operation of the railway, the jacking-out construction method was adopted. The ABAQUS finite element software was used to establish a three-dimensional model of the box culvert and soil body of the relying project, and three excavation thickness (0m, 1 m, 2 m) were used as the main variation parameters for numerical analysis and research, and the change law of the box culvert itself and soil body stress during the culvert jacking out process was obtained. The results show that the jacking force-displacement curves of the three working conditions can be divided into two stages, and the jacking force reaches the maximum value at the moment when the static friction turns into sliding friction at the end of the first stage. The stress distribution at the bottom slab of the box culvert in the jacking process is approximately normal, and the stress decreases with the increase of the roadbed excavation thickness. The increase of the roadbed excavation thickness can reduce the soil pressure on the side of the box culvert and effectively reduce the deformation of the roadbed in the jacking-out process. The deformation of the roadbed during the jacking process can be reduced by increasing the thickness of the roadbed excavation. 展开更多
关键词 Existing Box culvert Jacking-Out Construction Excavation Thickness Jacking Force
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Seismic Performance Assessment of Reinforced Concrete Box Culverts under Near and Far Fault Seismic Ground Motion Records
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作者 Lawali Moussa Laminou Wadslin Frenelus +1 位作者 Md Ratan Bhuiyan Md Ibrahim Bhuyan 《World Journal of Engineering and Technology》 2022年第1期40-58,共19页
Studying the critical response characteristics of reinforced concrete box culverts with diverse geometrical configurations under seismic excitations is a necessary step to develop a reasonable design method. In this w... Studying the critical response characteristics of reinforced concrete box culverts with diverse geometrical configurations under seismic excitations is a necessary step to develop a reasonable design method. In this work, numerical analysis and assessment of reinforced concrete box culverts for seismic loading in addition to standard static loading from dead and live loads is conducted, aiming to highlight the critical difference in the seismic performances between two and three cell box culverts under near and far-fault ground motion. The results show how and where the seismic loading alters the responses of seismic loading of the models including the effect on safety and failure. The geometrical configurations of the culvert combined with the loading scenarios also significantly influence the magnitude and distribution of the seismic responses. The findings of this work shed light on the critical role of the geometrical configurations and shaking event in the seismic responses of reinforced concrete box culverts and this procedure can be applied as seismic assessment method to any culvert shape, size, and material. 展开更多
关键词 Box culvert Seismic Loading Near-Fault Ground Motion Far-Fault Ground Motion Seismic Assessment
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A CAD Process for Box Culvert Structure Design
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作者 ZhangMengmei ShiFazhong ShiWeixin 《Computer Aided Drafting,Design and Manufacturing》 2003年第1期1-5,共5页
CAD process for structure design of box culvert is introduced. It follows the traditional way of culvert design. All working conditions of culvert are taken into account. It can generate load diagram, bending moment d... CAD process for structure design of box culvert is introduced. It follows the traditional way of culvert design. All working conditions of culvert are taken into account. It can generate load diagram, bending moment diagram and bending moment envelope diagram for a single-hole, double-hole or triple-hole box culvert .That is to say, the whole CAD process for the box culvert structure design is realized with the self-developed system. It has been used to accomplish several projects in China and the results are satisfactory. 展开更多
关键词 box culvert structure design visual C++ CAD
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Research on 3D visualization design system of hydraulic culvert
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作者 Wang Ziru Zhang Fan +2 位作者 Qiu Bing Wang Gongyan Ma Baiyu 《Computer Aided Drafting,Design and Manufacturing》 2016年第4期1-4,共4页
The conventional 2D design method of culverts separated from 3D model cannot directly visualize the process of creating and renewal process. This paper explores graphics application framework of Open GL based on MFC, ... The conventional 2D design method of culverts separated from 3D model cannot directly visualize the process of creating and renewal process. This paper explores graphics application framework of Open GL based on MFC, developing the 3D visualization system of hydraulic culvert. This system effectively integrats with building design, structural design and parametric design and image processing technology. The results can be shown by 3D visualization design. 展开更多
关键词 hydraulic culvert PARAMETERIZATION Open GL MFC 3D visualization
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Utility Impact below Bridge or Culvert Soffit on Open Channel Flow
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作者 Rodney McDermott Sarah Quinn 《Open Journal of Modern Hydrology》 2023年第4期193-210,共18页
The background to this research was a flooding incident that occurred in Bridgend, Co. Donegal, Ireland in August 2017. While several properties were flooded, a flooding case study of a single dwelling house adjacent ... The background to this research was a flooding incident that occurred in Bridgend, Co. Donegal, Ireland in August 2017. While several properties were flooded, a flooding case study of a single dwelling house adjacent to the Bridgend River at Riverdale, Bunamayne, Co. Donegal, Ireland is used herein. For this study the flooded site shall be referred to as the “Hegarty property”. A structure in the form of a stone arched culvert is located directly adjacent to the two-storey detached dwelling house on the Hegarty Property. While the culvert is referred to locally as a bridge, within this research the word culvert will be used in connection with the structure. The culvert has a concrete surrounded utility (watermain) crossing at a gradient below the culvert soffit on the upstream face of the structure. The utility obstructed flow through the culvert and contributed to the flooding event. Given the implication of climate change and the increased probability of more extreme flooding events, it was decided to explore the case study to ascertain the factors that contribute to flooding events when utilities are positioned at culvert or bridge structures. This work was completed to assist undergraduate students, researchers, and local authorities in a relatively unknown area of flood causation. 展开更多
关键词 UTILITY BRIDGE culvert Hydraulics FLOODING Climate Change & Open Channel Flow
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梯形沟谷地形下高填方箱涵涵周土压力离心试验研究 被引量:1
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作者 冯忠居 姚婉婷 +2 位作者 王伟 王思琦 王溪清 《建筑科学与工程学报》 北大核心 2025年第3期158-171,共14页
梯形沟谷地形下高填方涵洞的涵周土压力较为复杂,且与上埋式及沟埋式涵洞差异较大。为探明山区梯形沟谷地形下高填方箱涵的涵周土压力特性,通过离心模型试验,研究了不同沟谷宽跨比B/D、沟谷坡度α对箱涵涵周土压力的影响。结果表明:梯... 梯形沟谷地形下高填方涵洞的涵周土压力较为复杂,且与上埋式及沟埋式涵洞差异较大。为探明山区梯形沟谷地形下高填方箱涵的涵周土压力特性,通过离心模型试验,研究了不同沟谷宽跨比B/D、沟谷坡度α对箱涵涵周土压力的影响。结果表明:梯形沟谷地形的沟谷宽度及坡度均对高填方箱涵结构受力存在不同程度的影响,且沟谷坡度在30°~60°、沟谷宽跨比B/D<3时影响程度最大;沟谷地形下高填方箱涵的涵顶垂直土压力、涵侧水平土压力及涵底反力均与沟谷宽度呈正相关关系,与沟谷坡度呈负相关关系;沟谷宽跨比B/D<3时,涵顶垂直土压力集中系数Ks<1,沟谷坡度α>30°后,涵顶垂直土压力开始由应力集中转化为应力扩散;建议进行高填方箱涵设计时,在确保边坡稳定的前提下,尽量保留原有的梯形沟谷地形,选择沟谷宽跨比B/D<3且沟谷坡度较大的区域跨越,以保证地形对箱涵的减荷作用。 展开更多
关键词 涵洞工程 涵周土压力 离心模型试验 高填方箱涵 沟谷地形 沟谷宽度 沟谷坡度
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Design and Construction Technology of Prefabricated Reinforced Concrete Slab Culverts
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作者 Qiang Yang 《Journal of World Architecture》 2023年第5期52-59,共8页
Compared with traditional cast-in-situ concrete slab culverts,prefabricated reinforced concrete slab culverts can be produced more quickly and has strong quality controllability,strong earthquake resistance,and repeat... Compared with traditional cast-in-situ concrete slab culverts,prefabricated reinforced concrete slab culverts can be produced more quickly and has strong quality controllability,strong earthquake resistance,and repeatability.They will be the primary production method of slab culverts in the future.This article offers a comprehensive review of the design and construction technology associated with prefabricated reinforced concrete slab culverts.The objective is to provide a valuable reference for related enterprises,enhance the quality of design and construction in precast pile configuration,and,in turn,contribute to the advancement of construction projects within our country. 展开更多
关键词 Slab culvert Prefabricated reinforced concrete Design points Construction technology
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大断面管幕箱涵顶进引起地表变形的解析解答 被引量:3
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作者 张坤勇 李丹阳 +1 位作者 张梦 沈小锐 《岩土工程学报》 EI CAS 北大核心 2025年第1期184-191,共8页
研究大断面管幕箱涵顶进全过程对土体变形和周围环境的影响,对于事前预测变形并控制施工扰动影响具有重要意义。基于Mindlin解答、修正Sagaseta公式等经典理论解答,分别考虑由正面推进力、摩擦力和土体损失等因素引起的地表变形,提出考... 研究大断面管幕箱涵顶进全过程对土体变形和周围环境的影响,对于事前预测变形并控制施工扰动影响具有重要意义。基于Mindlin解答、修正Sagaseta公式等经典理论解答,分别考虑由正面推进力、摩擦力和土体损失等因素引起的地表变形,提出考虑三者共同作用下的大断面管幕箱涵顶进引起的地表变形计算方法。建立管幕箱涵顶进作用下土体受力模型,采用Mindlin解答分别给出正面推进力和摩擦力引起的土体变形计算公式;基于当层法原理提出由土体损失引起的横向地表沉降计算公式。根据各影响因素的相对独立性,将各因素引起的土体变形量叠加,从而得到一种适用于大断面管幕箱涵顶进施工,可综合考虑多种施工因素和土体三维变形的理论解答公式。通过工程实例验证公式的合理性,研究成果可为实际施工变形预测提供参考。 展开更多
关键词 大断面管幕箱涵 MINDLIN解 地表变形 变形预测
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设置挡水隔板的鱼类友好型涵洞水力特性试验研究 被引量:1
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作者 毛劲乔 陆鹏 +2 位作者 龚轶青 高欢 戴杰 《长江科学院院报》 北大核心 2025年第7期104-111,共8页
涵洞是沟通河系、连接生物生境的重要通道,在其中布置小型挡水结构可有效减小局部流速,增加弱游泳能力鱼类上溯成功率,提高涵洞的生态效益。为明确设置三角形挡水隔板涵洞内水力特性,在水槽单侧布置多个三角形挡水隔板模拟涵洞中的小型... 涵洞是沟通河系、连接生物生境的重要通道,在其中布置小型挡水结构可有效减小局部流速,增加弱游泳能力鱼类上溯成功率,提高涵洞的生态效益。为明确设置三角形挡水隔板涵洞内水力特性,在水槽单侧布置多个三角形挡水隔板模拟涵洞中的小型挡水建筑物开展水槽试验研究,利用SonTek声学多普勒流速仪(ADV)采集三维流速数据,分析挡水隔板后流速分布、湍流特性、动量输运模式等,论证增设三角形挡水隔板系统对促进弱游泳能力鱼类(小鳈)上溯行为的可行性。研究结果表明:增设三角形挡水隔板,主流区流速仍能维持为25~30 cm/s,对主流区流速影响较小;在隔板边壁产生稳定的低速区(LVZs),其流速为-4~15 cm/s,相较光滑侧壁水槽低速区的面积占比由5%~10%增加为14.80%~18.07%;挡水隔板下游低速区水流湍动能和雷诺应力明显大于无挡水隔板侧的高速区,但未超过相应的鱼类游泳偏好阈值;水流动量交换以喷射和扫掠形态为主,该瞬时形态可提供更适宜弱游泳能力鱼类游动的流动环境。 展开更多
关键词 涵洞 水槽试验 挡水隔板 低速区 动量交换
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简易暗渠构建机的设计与试验
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作者 周魏岩 张海滨 +3 位作者 王秋菊 齐忠军 梁玉成 陈爱慧 《农机化研究》 北大核心 2025年第11期156-161,共6页
为适应白浆土土壤改良需求,解决排水沟边坡坍塌、杂草过度生长,以及地下排水系统排放率低导致地下水位升高、土壤养分流失障碍等问题,设计了一种简易暗渠构建机。根据农业要求对整机结构和关键工作部件进行了设计,将推土铲优化设计成半... 为适应白浆土土壤改良需求,解决排水沟边坡坍塌、杂草过度生长,以及地下排水系统排放率低导致地下水位升高、土壤养分流失障碍等问题,设计了一种简易暗渠构建机。根据农业要求对整机结构和关键工作部件进行了设计,将推土铲优化设计成半径为550 mm半圆弧,选取侧切壳深度为350~600 mm,并通过田间试验验证了机具设计的合理性和可靠性。试验结果表明:当整机行驶速度为2.83 km/h、暗渠最小间距为7.50 m、作业深度为475 mm时,作业效果最佳;此时,土壤的水分含量为19.60%,达到了设计要求,可为白浆土机械化土壤改良提供可靠的技术装备。 展开更多
关键词 构建机 暗渠 推土铲 侧切壳
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