路基

Highway subgrade Highway subgrade may be defined as the supporting structure on which pavement and its special undercourses rest .in cut sections ,the subgrade is the original soil lying below the special layers designated as base and subbase material .in fill section ,the subgrade is constructed over the native ground and consists of imported material form nearby roadway cuts or from bowwow pits.

公路路基公路路基可界定为支撑结构对路面和特殊undercourses休息。在削减部分，路基是原来的地势低于土壤的特殊层指定为基础和基层材料。填补节中，路基建造的本地地面，由进口物质形式附近的巷道削减或从bowwow坑。

In this paper,Laterite soil adjacent to some stake of the highway in Chenzhou, Hunan section from Xiamen to Chengdu was used to investigate the deformation characteristics and protection methods of the Laterite soil subgrade under the influence of environment factors.Properties like water-holding capacity,capillary rise, coupled heat-moisture transfer and wetting deformation of samples under different compactness were studied through a series of laboratory tests.In addition,by using meteorological data of two consecutive years in Chenzhou,coupled process of moisture transfer and subgrade deformation was stimulated under the impacts of groundwater and the atmosphere.Specific work done in this paper is as follows:(1) Samples under different compactness were subjected to a series of conventional laboratory tests,such as permeability,consolidation,contraction,shear test and etc.

论文以厦门至成都高速公路湖南郴州段的红粘土为研究对象，以环境因素作用下红粘土路基的变形特征与防护方法为研究目的，通过室内试验研究了不同压实度红粘土的持水性能、毛细上升、湿热耦合迁移及湿化变形等特征，借助郴州地区连续两年的气象数据，模拟在地下水和大气的共同作用下路基内部红粘土水分迁移与路基变形的耦合过程，主要研究内容及结论如下：(1)针对不同压实度的红粘土，系统开展了其渗透、固结、收缩、剪切等试验研究。

Research purposes: The anti- frost heaving measures for the surface of subgrade in permafrost region and the anti-heat thawing measures for the subgrade of poor and rich ice frozen soil are put forward based on the analysis of the characteristics of surface frost heaving and bottom thawing of subgrade in permafrost region.

研究目的：本文从分析冻土区路基表层的冻胀特征和底层的融沉特征入手，提出路基结构设计中冻土区路基表层的防冻胀措施以及低含冰量冻土和高含冰量冻土路基的防热融措施。

Our country firstly put forward such design principle of Qinghai-Tibet railway engineering as "lower temperature actively, reduce the heat into the subsoil, and assure the heat stability of frozen earth for the quality stability of construction", creatively adopt such corresponding measures of frozen earth construction problem as: for the poor frozen earth developing section, line should avoid as possible;for the geology of ice at high temperature and unstable frozen earth zone, the method of bridge instead of subgrade shall be adopted;in subgradeconstruction, such facilities as heat stick, rubble ventilation subgrade , rubble ventilation berm, ventilation pipe subgrade and laying heat preservation board etc shall be adopted to raise the stability of frozen earth subgrade;during the excavation of bridge, culvert , foundation pit and scouring prevention trough, creatively adopt single-tooth knapper and solve the problem of frozen earth excavation;during the construction of bridge and culvert, durable concrete and three-step maintenance method are adopted to assure the outside and inside beauty of structure.

我国在世界上首次提出"主动降温、减少传入地基土的热量、保证多年冻土的热稳定性，从而保证修筑在上面的工程质量的稳定性"的青藏铁路工程设计原则，创造性地采取了解决冻土施工难题的相应对策：对于不良冻土现象发育地段、线路尽量绕避；对于高温极不稳定冻土区的高含冰量地质，采取"以桥代路"的办法；在路基施工中采用了热棒、片石通风路基、片石通风护道、通风管路基、铺设保温板等多项设施，提高冻土路基的稳定性；在桥涵基坑、挡水埝基槽开挖中，创造性地应用了单齿破碎器，解决了冻土开挖难题；在桥涵工程施工中，采用了耐久性混凝土，采用了三步养生法，保证了结构物内实外美。

The heat preservation effect of the awning can be seen after one awning. After a cycle of cold and warm seasons, an awninged embankment temperature is 3~5℃ lower than an ordinary embankment, and the permafrost table ascends 1.0~1.7m, with an average of 1.1m, under the berm, the road shoulder and the road center.

遮阳板措施的保温效果在应用只有1a的时间里面就表现出来，在第1个冷暖季节过后，在遮阳板保护下的路基土体温度就较普通路基低，在路基左路肩部位低出3~5℃；在路基的左右护道、路肩孔和中心孔冻土上限抬升在1.0~1.7m，平均抬升1.1m。

According to by the time series estimate power spectral density\'s periodogram law principle,the research adopts five level of orbital power spectra which US Federal railway Administrative bureau FRA proposed;then,through the Fourier inverse transformation,the orbital not smooth time domain samples are obtained, which determine the track irregularity peak-to-peak value and the corresponding wave length; on the basis of the research,the influence of the wheel track dynamic contact force are considered.Based on the orbital roadbed coefficient\'s definition,computation model is established to solve the roadbed equispaced spring constant,and the roadbed uniform spring stiffness is obtained by using the numerical simulation method.Finally,based on the Matlab procedure platform,the computational procedure is established,and the load time interval caused by the moving train acts on the roadbed is obtained.

根据由时间序列估计功率谱密度的周期图法原理，采用美国联邦铁路管理局FRA提出的五级轨道功率谱，通过Fourier逆变换得到轨道不平顺的时域样本，确定了轨道不平顺的幅值及对应的波长，以此为基础考虑轮轨动态接触力的影响；基于轨道路基系数的定义建立了求解路基均布弹簧刚度的计算模型，采用数值模拟得到了路基均布弹簧刚度；最后，基于Matlab程序平台编制了计算程序，得到了运行列车作用到路基上的荷载时程。

The results show that the vehicle acceleration, the dynamic wheel load and offload factors increase with train speed, and distribute linearly. The safety of train operation and running comfort can meet the requirements when the high-speed train under secondary suspension passing through ballasted track subgrade structure. The dynamic displacement of the system is less influenced by train speed. The dynamic stress of subgrade surface increases with speed improving, and it is distributed as saddle along the lateral direction and as parabola along the longitudinal direction of subgrade surface. The dynamic stress of subgrade declines sharply along the depth of subgrade. The dynamic stress on 3 m depth below subgrade bed surface is about 16 percent of that of subgrade surface.

结果表明：车体加速度、动轮载和轮重减载率均随车速的提高而增大，呈线性分布；具有二系悬挂的高速列车通过有砟轨道路基结构时，列车的安全性及舒适度均能满足要求；系统动位移受速度影响较小；路基面动应力随速度的提高而增大，并在横向呈马鞍形分布，在纵向呈抛物线形分布；路基动应力沿路基深度方向衰减较快，在基床表面下3 m处，动应力只有基面的16%左右。

Based on Tseng-Lytton evaluation model for permanent deformation, and evaluation model for permanent deformation of clayed subgrade soils is established by improving and calibrating Tseng-Lytton model.

利用室内重复荷载三轴试验，研究了在含水量、压实度和偏应力影响下粘性路基土的永久变形特性，并以Tseng-Lytton路基土永久变形预估模型形式为基础，对Tseng-Lytton模型进行了改进和标定，建立了粘性路基土的永久变形预估模型；最后利用分层应变总和法，并结合一个典型粒料柔性基层沥青路面结构实例，计算了路基土的永久变形量。

His statement about the number of Salukis registered around the world is totally wrong, in England last year there were many people from either the South or the North ( depending on where the show was ) that didn't attend a show and yet there were still over 100 Salukis entered at each show, plus there were many with the owners that were not entered.

Falcon关于注册萨路基数量的说法是完全错误的。去年在英国，许多来自南部或北部的人没有带自己的萨路基参加犬展，但是参加每场犬展的萨路基仍然超过100只，而没有登记参赛的萨路基还有很多。

Comparison results show that heat pipe work is not continuous but fluctuant in one work cycle about five months,its actual working time is two-thirds of one work cycle,the cooling effect of heat pipe subgrade in winter is obvious,which is good for the contained cool increase of soil body and improves subgrade heat stabilization,there is a decrease for its cooling strength with the increase of horizontal distance,its effective operating radius is 2.25 m,its maximum cooling strength is in evaporation segment in depth direction,which low the thaw sensitivity of permafrost in the seasonal thaw layer about permafrost table.

研究发现，热棒在约为5个月的工作周期内并非连续工作而呈波动式，实际工作时间为工作周期的2/3；热棒路基冬季降温效果明显，有利于路基土体冷储量增加，提高路基热稳定性；热棒在路基中的降温强度，水平方向随距离增大而衰减，有效作用半径为2.25 m，深度方向在热棒蒸发段最大，降低上限附近季节融化层冻土热融敏感性。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。