流固耦合的多元结构深厚覆盖层透水地基的力学特性

深厚覆盖层多元结构坝基在渗流过程中各土层力学差异明显，分析时关注的具体问题也不尽相同，需要深入研究。基于比奥固结理论，考虑土体的非线性流变以及土体固结变形过程中孔隙度、渗透系数、弹性模量及泊松比的变化；借助ADINA流固耦合模块来模拟西藏达嘎水电站坝基渗流场与应力场耦合过程，分析各层力学特性及相互作用。研究表明，透水性较强的表层土体是渗流主要通道，也是渗流进出区和沉降变形体现区，应在上游采取措施提高其压缩模量，下游区域增设反滤层和排水设施；坝基中的粉细砂层是坝基沉降的主要原因，对坝基沉降起主导作用，同时应注意其液化特性对坝基的不利影响；坝基中的承压含水土层对下游上部结构产生向上顶托力，若位置较深，则破坏性较小；坝基深部土层对整个坝基的渗流破坏影响较小，但对沉降和渗流量的影响不可忽视；表层砂卵砾石层和粉细砂层的渗透系数相差较小时，土层间不会发生接触冲刷。此外，还发现坝基孔隙水压力在快速衰减阶段被消散，期间土体固结较快。垂直防渗墙能有效降低渗透坡降和渗流量，将坝基沉降变形控制在防渗墙上游区域，但上游坝基变形对防渗墙产生较大的水平推力，应加大防渗墙尺寸或者采用辅助渗控措施。     

Settlement Analysis on Building near Retaining Pile of Deep Foundation Pit

The building settlement near a foundation pit project in Yanzhou is calculated by using calculation method related to settlement of the soil near a foundation pit, Comparing and analyzing calculated settlement values with measured settlement ,the reason for the gap between theoretically calculated values and measured settlement values is pointed out, On the foundation of careful research and analysis of the measured building settlement values ,the factors influencing the settlement of building near the foundation pit are summarized. Finally, according to practical measured values and influ- encing factors, how the settlement of building near the foundation pit is influenced was carefully analyzed. A conclusion that has practical role in Engineering is presented,which can serve reasonably for instructing foundation pit retaining design.     

基坑开挖及降水对坑外地表沉降的影响

考虑降水、支护结构变形以及基坑隆起3个因素引起的基坑周围土体的沉降,根据降水引起土体沉降的机理,运用修正的分层总和法单独计算出由降水引起的周围土体沉降。通过研究基坑开挖引起坑外土体沉降的规律,推导出由基坑开挖引起的坑外土体沉降理论公式。把降水引起的沉降及基坑开挖引起的沉降进行叠加,加入修正系数,最终以简化的理论公式合理地计算出基坑周围土体沉降。具体工程验证表明,推导的理论解析解与实测数据十分接近,能有效预估基坑周围土体沉降,为施工方案编制提供可靠的理论依据,最大限度减少基坑施工对周围环境的影响。     

Study on Consolidation of Reinforced Soft Foundationwith Two-way Drainage of Sand Well

Based on traditional consolidation theory, the soft ground settlement is calculated and one-, two-, and three-dimensional consolidation of reinforced soft foundation with sand drain is studied. The calculation method of average sand drain and the new modified method are discussed. The results can serve as a guide to subgrade design of soft ground.     

Reinforcement Treatment on the Uneven Subsidence of Foundation

There are several methods to cope with the common problem of the uneven subsidence of foundation. The reason for uneven settlement of foundation of the frame structure was analyzed in this paper. Considering the limitation of the construction site and the principle of consolidation, a feasible reinforcement measure was taken. Meanwhile, a practical construction pattern was chosen upon the comparison of the reinforcement technology analysis and the construction method. The observation of the settlement result after consolidation of the structure shows that the result of this reinforcement treatment pattern is effective.     

河南省土地开发整理潜力分区研究

本研究为河南省土地利用总体规划修编、耕地占补平衡目标实现提供前期研究。借助Mapinfo与VBA建立土地开发整理潜力调查数据库,建立潜力测算模型。通过区域权属图库的快速构建、区域地形条件、区域农民收入基础数据库的建立,以及农田整理、村庄整理、土地开发和土地复垦潜力测算,借助GIS实现土地开发整理潜力综合评价,并对土地整理重点区域和重大工程的划分标准进行了分析。笔者研究将河南省划分为十个土地开发整理潜力分区,确定了农田整理、村庄整理、土地开发和土地复垦重点区域,同时确定了河南省五大土地开发整理重大工程。     

On Elasto-Plastic Consolidation Settlement of Saturated Soft Clay

The specific properties of soft clay are characterized by higher void ratio, lower permeability and higher compressibility, the consolidation settlement of soft clay is affected by the imposed stress history, the stress paths, the consolidation pressure and the soil properties. In this paper, the porous media theory based on the mixture theory was applied in the study on the consolidation settlement of soft clay, which was more rigorous than the conventional consolidation settlement theory and the coupling between soil and water can be taken into account in the analysis.     

Improved Least Square Method for the Consolidation Coefficient Evaluation

At present, the logarithm of time and the square root of time methods are usually used to compute consolidation coefficient, from which only a few data were adopted for the consolidation coefficient. At the same time, the two solutions depend on the initial value from the curves and influenced the exactitude of consolidation coefficient directly. So, in this paper, an improved least square method is supposed to compute the consolidation coefficient with testing data. According to the derived formulae, a program is used to compute consolidation coefficient based on Matlab language and to eliminate human error. The computation results show a good effect and give a reduction of errors.     

An Improved Grey Relation Model of Safety Evaluations of Evacuation from High rise Building Fires

Based on a study of the time process of individual evacuees in high rise building fires, we found that the low security influencing factor will affect the possibility of successful evacuation severely. The traditional grey relational grade cannot reflect the effect of the grey relational coefficient fluctuation. Moreover, the single weight calculation with a subjective or objective weight will also directly affect the evaluation result of safe evacuation during high rise building fires. Based on these analyses, the grey Euclid relative grade was applied to indicate the effect of the grey relational coefficient fluctuation. The Spearman correlative rating coefficient was used to combine the subjective and objective weights to eliminate the deficiency of the single weight case. We discuss the possibility of applying the improved grey relational evaluation. Comparing the evaluation results, we found that the weight combination and grey Euclid relation applied in a safety evaluation model can improve evaluation result accuracy. The evaluation model thus corresponds to the characteristics of high rise building fires and the weight set substantially affects the evaluation result.     

Analysis on Foundation Pit Deformation of a Commercial Building in Hangzhou

The foundation pit deformation of a commercial building in Hangzhou is calculated by using calculation method related to foundation pit deformation. The calculation results by m method show that the maximum deformation is 29.2mm and the real maximum deformation is 174.6mm. The deformation character obtained by foundation coefficient method is different from the real deformation. There are lots of factors influencing foundation deformation. According to practical engineering condition, in this study, the influencing factors for soil parameters, bracing condition, condition for insertion of retaining wall into soil and construction speed are determined. The calculation method used is analyzed and modified. Finally, a useful and valid method for calculating foundation deformation is presented, by which the foundation pit deformation in practical project can be forecasted and analyzed.     

FEM Analysis of Differential Settlement of Gravel Pile Foundation Under Large scale Oil Tank

In order to reduce the differential settlement of gravel pile foundation under large scale oil tank, axisymmetric numerical simulation method and finite element method was employed to study the pile length, the exchange rate of length, the length of the cushion course to the influence of differential settlement and the relationship of negative lateral displacement and the settlement. It is found that: differential settlement has a minimum range of pile length. For the oil tank foundation center, by keeping the pile diameter, increasing pile spacing can increase the rate of exchange and obtain smaller differential settlement in relatively smaller displacement rate conditions. And by keeping replacement rate unchanged, the larger the pile diameter(namely the looser pile spacing) is, the smaller the differences settlement of the gravel pile foundation is. Moreover, pile length adjustment and the exchange rate have obvious effects on different subsidence and not obvious effects on the length of the cushion course. The appearance of oil tank foundation negative lateral displacement is one of the most important features of differential settlement adjustment.     

Optimum Design for Pile Group Foundation and ItsApplication in Factory Building

On the basis of discussing the damage mechanism of cushion cap, a method of optimum design for pile group foundation is put forward in this paper.The piles are decorated on the cushion cap which makes the area of cushion cap minimum.The object function of optimum design for cushion cap is its volume and the binding functions are the requirements of shear, column die cutting, corner-pile die cutting and settlement for cushion cap.The optimum design has been done by a computer program. This method is used to design a factory building. The final result suggests that this method is highly effective and practical. A fair-scale economic efficiency can be obtained in ifs practical use.     

Deformation of Soft Ground with Consideration of the Concomitant Damage

On the basis of continuum damage mechanics theory, the effective stress theory of damaged porous media was presented and its modified self contained seepage differential equation was deduced. The traditional Drucker Prager yield criterion subsequently was modified, and a coupled seepage and damage finite element computer program compiled that was combined with the modified Biot consolidation equation. A simple roadbed foundation model then was analyzed and calculated using the computer program we compiled, and the typical node settlement, pore pressure, and damage variables were discussed and compared with those from the analytic solution. The results show that the damage finite element program we compiled is reasonable and effective.     

Contrast Analysis of the Reinforcement Effect of Pile-Net Composite Foundation

To investigate the effect of consolidation soft soil, three groups of model tests were designed. The first group was PVC pile-net composite foundation, the second was pile-cap-net composite foundation, and the third was PVC and sand pile composite foundation. Butter was coated and plastic membrane was covered on inner side wall of model cast to reduce border effect. The gauges were glued with epoxy on the surface of the model with PVC piles and geogrids to measure the stress of PVC piles and geogrids. Soil pressure cells were installed in the middle of piles and the top of the sand piles, and dial indicators were installed in the middle of road and road shoulder to measure deformations. It is that shown: 1) as for the distribution of the road settlement and the differential settlement, the settlements of the third group are the largest and those of the second group are the least; 2) in terms of the stress ratio of PVC pile and soil, the values of the first group and the third group are similar, while the value of the second group is much larger; 3) the change of geogrid strain is disorderly. There are periodic peaks in the strain of geogrid of pile top and periodic troughs in the soil between the piles. The geogrid strain of the second group measured in the corresponding spot is much larger than those of the other two groups. The results of three groups of tests illustrate that if the condition is permitted, it would be the best to adopt the scheme of pile-cap-net composite foundation, which has better reinforcement effect for soft soil.     

半山丘陵区居民地空间分布的特征及其优化分析

为了掌握半山丘陵区居民地空间分布的变化特征,对居民地布局进行优化,为居民地规划和整理的实施提供重要依据。以地处长白山系半山丘陵区的海林市为研究区,结合TM、DEM影像等相关资料,分别从海拔、坡度、坡向、交通、水源五方面对居民地的空间特征进行了定量分析,采用特尔斐法对选取的指标赋予权重并逐一打分,并根据研究区人口、经济,人文等情况,将研究区的居民点划分为搬迁型、保留型及发展型,并进行优化。结果表明,随着海拔、坡度的增加,居民点数量、面积逐渐减少,在北方地区坡向为正北向的居民点面积最少。交通、水源与居民点的空间分布具有显著相关性。根据优化方案确定搬迁型居民点148个,保留型居民点1632个,发展型居民点40个。     

山东半岛滨海乡村建筑聚落景观建设研究——以荣成市俚岛镇为例

山东半岛滨海乡村建筑聚落在早期建设中遗留了许多“城市化”问题。本文通过对这些问题的具体分析,提出山东半岛滨海乡村建筑聚落更新坚持动态保护、文化传承和可持续性三大原则,并以荣成市俚岛镇为例,从建筑聚落优化和加强对当地居民保护意识引导两方面提出保护与利用山东半岛滨海传统乡村建筑聚落的措施,以此优化建筑聚落景观。     

玉门市农村居民点整理适宜性评价研究

为了合理有序的开展农村居民点整理工程,指导农村居民点整理顺利进行,以玉门市农村居名点用地作为研究对象,采用多因素综合法对玉门市农村居民点整理的适宜性进行了评价。结果表明：玉门市农村居民点整理的适宜类型可以划分为3类。其中适宜整理的农村居民点面积为1573.58hm²,占全市农村居民点总面积的56.93%,主要分布于清泉乡、柳河乡、昌马乡、花海镇、赤金镇;较适宜整理的农村居民点面积为908.90hm²,占全市农村居民点总面积的32.89%,主要分布于下西号乡、黄闸湾乡、玉门镇;暂不适宜整理的农村居民点面积为281.48hm²,占全市农村居民点总面积的10.18%,主要分布于柳湖乡、小金湾乡。通过分析得出其适宜的程度与经济发展状况、交通便利程度、居民点分散度等密切相关。该研究结果可为开展玉门市农村居民点整理工作提供参考。     

A study on lateral deformation calculation of foundation under embankment

Embankment load causes not only vertical settlement of foundation but also lateral deformation of foundation, and lateral deformation is one of the important factors for foundation settlement. In order to analyze lateral deformation of foundation under th     

沉积作用及应力历史对自重应力和沉降的影响

土体的沉积作用和应力历史会影响土体自重应力的确定，也会影响地基最终沉降量的确定。鉴于e-lnp比e-lgp坐标图能更方便、精确地描述线性问题，根据e-lnp坐标图推导沉积作用对成层土、正常固结土、超固结土的自重应力与沉降影响的计算式。用该计算式对昆明滇池国际会展中心部分深厚软土地基的自重应力和最终沉降量进行计算，并用计算结果和不考虑沉积作用及应力历史影响的计算结果进行对比分析，结果表明，沉积作用对深厚软粘土自重应力和最终沉降量计算值的影响非常显著，并且土体厚度越厚、上覆荷载越大，其影响越明显。     

Double-Face Dynamic Balance Method of Spot Rotator without Removing the Test Weights

Site dynamic balance is a important element in installation and maintenance of heavy rotary mechanism. It's hard to discharge testing weights, and the remanent weights will effect the result of balance test. The paper presents a kind of dynamic balance algorithm which need not to discharge the test weights, basing on influence coefficient. The principle of the algorithm is to balance the sum of original unbalance weights and testing weights by the result balance weights. In the algorithm , the influence coefficient of last time can be used optionally for the same rotor. Then developing a dynamic balance system building on it. The site experimental results indicates that this algorithm has a high balance precision, predigests the steps and reduces the operation time.