淮河姜家湖 唐垛湖行洪堤退建工程效果分析

本文简述了淮河中游姜家湖、唐垛湖行洪区概况和退堤情况,通过其对河道泄量、行洪、堤防、土地的影响分析了工程的效果。

寿西淮堤退建对淮河干流正凤段河道泄洪能力的改善

1、正阳关至凤台段河道状况 淮河干流正阳关至凤台段(简称正凤段)河道长44.2km,河线弯曲,比降平缓,局部河段束水严重,排洪不畅。该段河道直线距离仅32km,河道弯曲系数1.4。河底平均高程为9.2m,主槽平均宽度378m,最窄处大朱台孜至黑泥沟管理段主槽宽度仅270m,平均堤距990m。寿西淮堤退建段堤距只有500～600m。通过历次测量资料分析,河道平面变化很小,主流线摆动不大,总体上较为稳定。

行洪堤退建工程堤身填筑施工中的质量控制

以荆山湖行洪区堤防为例,对行洪堤退建工程堤身填筑施工中的质量控制注意的问题等进行探讨,以供参考借鉴。

紧邻高层建筑物防洪墙退建工程施工技术

芜申运河城区段防洪墙退建工程紧邻长江长、水木年华等高层住宅小区,施工条件复杂,对变形控制要求高。为了确保防洪墙退建工程的如期建成和周边高层建筑物的稳定,通过对多种桩基综合运用及边坡卸载方案的优化,并在施工中对基坑周围的地基变形及影响区内的建筑物安全进行监测,最终顺利地完成了项目的建设开发及保护任务。

双向搅拌桩复合地基在新建码头退建堤防堤基中的应用

近年来,双向搅拌桩在我国公路、铁路、水利建设行业软土地基处理中取得了广泛应用,但在堤防建设,尤其是结合临近码头的堤防建设领域鲜见双向搅拌桩的应用。文章结合工程实例,介绍了双向搅拌桩在新建码头退建堤防堤基中的应用。

淮河蚌埠以下河道治理前后糙率变化

为了给平原河道治理工程提供参考和借鉴,针对淮河蚌埠以下河道建立一维水动力模型,采用1991年及2008年测量的河道断面资料及相应的实测洪水资料率定模型,就河道治理前后的糙率参数变化进行分析评价。结果表明:对于无水生植物生长的平原河道,经过挖泥船水下作业、局部堤防退建、抛石护岸等治理后,主槽和滩地的糙率均有不同程度的增加。

河道防洪能力提高的对策及影响因素分析

以某高新区河道生态综合整治工程为例,分析了工程河段现状情况及存在的问题,根据水文计算成果提出了堤防退建和堤防加高培厚2种方案,并通过防洪要求、施工影响、建设征占地、安全稳定、与城市景观结合、经济合理等方面分析了2种方案优缺点,综合比选采用了堤防退建方案,将工程河段从现状10年一遇提高至50年一遇的防洪标准,提出了河道生态综合治理工程中提高河道防洪能力的对策及主要影响因素。

Diagnostic model construction and example analysis of habitat degradation in enclosed bay:Ⅲ. Sansha Bay habitat restoration strategy

Unbalanced inputs and outputs of material are the root cause of habitat degradation in Sansha Bay,Fujian Province,China. However,the cumulative pollution varies in different geographic locations and natural conditions in the enclosed bay. In this study,hydrodynamic conditions,sediment characteristics,and aquaculture methods were recognized as the underlying causes of spatial heterogeneity in the distribution of nitrogen and phosphorous pollutants,the two major controlling factors of habitat degradation in the bay area. In order to achieve the goal of balancing nutrient inputs and outputs in Sansha Bay,we developed a feasible and practical zone restoration strategy for reasonable adjustment and arrangement of aquaculture species and production scale in accordance with varying hydrodynamic conditions and sediment characteristics in six sub-bay areas(sub-systems). The proposed zone restoration strategy lays a solid foundation for habitat restoration and management in Sansha Bay.

Finite Element Analysis and Linear Regression of Maximum Temperature for Inner Wall of Chimney Foundation

The uniform design method was adopted and the twenty-four groups of different geometric and physical pa-rameters were chosen. The finite element model was built. Comparisons between the simulation results and the test re-sults prove that the simulation results are correct. The distribution of the temperature field of the chimney foundationwas analyzed. The multivariate linear regression of the hightest tomperature was performed on the inner wall of thechimney foundation by the numerical calculated results. The fitting property of the highest temperature with six influ-ence factors was obtained. A simple method for the calculation of the temperature field of the chimney foundation wasprovided.

Diagnostic model construction and example analysis of habitat degradation in enclosed bay: I. diagnostic model construction

Presently, research is lacking regarding the diagnosis and evaluation of habitat degradation in enclosed bay systems. We established a diagnostic model for enclosed bay habitat degradation(EBHD model) using a multi-approach integrated diagnostic method in consideration of driving force-pressurestate-infl uence-response. The model optimizes the indicator standardization with annual average change rate of habitat degradation as the basic element, to refl ect accurately the impact of the change and speed of degradation on the diagnostic results, to quantify reasonably the contribution of individual diagnostic indicator to habitat degradation, and to solve the issue regarding the infl uence of subjective factors on the evaluation results during indicator scoring. We then applied the EBHD model for the Sansha Bay in Fujian Province, China, evaluated comprehensively the situation of habitat degradation in the bay, and screened out the major controlling factors in the study area. Results show that the diagnostic results are consistent in overall with the real situation of the study area. Therefore, the EBHD model is advantageous in terms of objectivity and accuracy, making a breakthrough in diagnosis and evaluation for habitat degradation in enclosed bay systems.

Diagnostic model construction and example analysis of habitat degradation in enclosed bay: II. spatiotemporal variations in habitat degradation in Sansha Bay

The process of habitat degradation varies in habitat type and driving force which shows certain spatial and temporal heterogeneity on regional scales. In the present study, a new diagnostic model for enclosed bay habitat degradation was established, with which the spatial and temporal variation patterns of habitat degradation during 1991–2012 in Sansha Bay, Fujian, China was investigated. The results show that anthropogenic disturbance is the major controlling factor for the habitat degradation in large temporal heterogeneity in the bay. On the other hand, the habitat degradation experienced signifi cant spatial variations among six sub-bays. Under the joint action of temporal and spatial heterogeneity, the degradation trend in growing scale shows a more signifi cant correlation with the distribution of local leading industries along shorelines. Therefore, we quantifi ed the main characters of habitat degradation in Sansha Bay, and have understood the relationship between the status of habitats spatio-temporal variation value and the main controlling factor leading to the changes. However, a defi ciency of this research is the lack of or inaccessible to the detailed data, which shall be better solved in the future study for accessing more data from more sources.

Fatigue behaviour of welded joints assembled by longitudinal corrugated plates

Fatigue is usually the cause for the cracks identified at bridge elements in service. With an increase in the introduction of corrugated steel web girders in recent highway bridge construction, the understanding of the fatigue behaviour of welded details in such structures becomes an important issue for the design. The typical welded details were represented as welded joints assembled by longitudinal corrugated plates. All the experiments were performed under fatigue loading using a servo-control testing machine. The test results from the failure mode observation with the aid of infrared thermo-graph technology show that the failure manner of these welded joints is comparable to that of the corrugated steel web beams reported previously. It is indicated from the stiffness degradation analysis that the welded joints with larger corrugation angle have higher stiffness and greater stiffness degradation in the notable stiffness degradation range. It is shown from the test S-N relations based on the free regression and forced regression analyses that there is a good linear dependence between lg(N) and lg(ΔS). It is also demonstrated that the proposed fracture mechanics analytical model is able to give a prediction slightly lower but on the safe side for the mean stresses at 2 million cycles of the test welded joints.

Distribution and Assessment of Soil and Land Degradation in Subtropical China—A Case Study of the Dongxi River Basin, Fujian Province *1

Some alternative methods for estimating soil erosion rates rapidly were used to elucidate the relationship between the land use types and land degradation. The 137 Cs content, magnetic susceptibility, aggregate stability, and soil properties were studied in the Dongxi River Basin, a mountainous area of western Fujian. A plot of 137 Cs inventory (Y) against slope angle (X) shows a strong inverse log log relationship ( r = -0.83 ), indicating that much more soil erosion occurs on steeper slopes. Average soil loss (in thickness of top soil per year) in the past 30 years for arable slope crest, arable slopes and tea plantation slopes are 1.6 , 10.4 and 8.0 mm year -1 respectively. The surface layer enrichment factor of magnetic susceptibility (Y) in soil also shows an inverse log log relationship ( r =-0.63), indicating a similar tendency with the relationship between the 137 Cs inventory (Y) against slope angle (X). The physical and chemical properties of soils among different land use types show different degraded characteristics at different significant levels.

Reconstruction of 3-D digital cores using a hybrid method

A 3-D digital core describes the pore space microstructure of rocks. An X-ray micro CT scan is the most accurate and direct but costly method to obtain a 3-D digital core. In this study, we propose a hybrid method which combines sedimentation simulation and simulated annealing （SA） method to generate 3-D digital cores based on 2-D images of rocks. The method starts with the sedimentation simulation to build a 3-D digital core, which is the initial configuration for the SA method. We update the initial digital core using the SA method to match the auto-correlation function of the 2-D rock image and eventually build the final 3-D digital core. Compared with the typical SA method, the hybrid method has significantly reduced the computation time. Local porosity theory is applied to quantitatively compare the reconstructed 3-D digital cores with the X-ray micro CT 3-D images. The results indicate that the 3-D digital cores reconstructed by the hybrid method have homogeneity and geometric connectivity similar to those of the X-ray micro CT image. The formation factors and permeabilities of the reconstructed 3-D digital cores are estimated using the finite element method （FEM） and lattice Boltzmann method （LBM）, respectively. The simulated results are in good agreement with the experimental measurements. Comparison of the simulation results suggests that the digital cores reconstructed by the hybrid method more closely reflect the true transport properties than the typical SA method alone.

Apartments for Elderly People in a Building Designed as a Retirement Home

The building as a model for conceiving a project： The future of the construction industry will be a science of what to do with the built environment rather than the classical problem of what is needed to be built. The necessary areas for living, working and entertainment are probably already built, but we need to update them to comply with the new codes, the new needs and the new uses of our society. For this reason we are looking at new ways of addressing our profession： Firstly we have to decide whether a new way of living requires a new space or if there is already an existing space available. Secondly, we have to adapt the chosen space to the new requirements of society and the new codes and regulations. Thirdly, we have to think about the sustainable and energetic needs, in order to update the building to the new efficiency requirements in terms of energy. Life cicle： We want to add a vision of life cycle to a building in terms of changing and updating. With this vision we are looking for ＂quality existing buildings＂ and for a way of designing ＂versatile frameworks＂ and layouts allowing for future renovation and refurbishments, Therefore our research is two pronged： （1） Identify examples of transformable buildings; （2） Looking for a design strategy that allows for easy changes of use.

Modeling, identification and compensation for geometric errors of laser annealing table

In order to improve the process precision of an XY laser annealing table, a geometric error modeling, and an identification and compensation method were proposed. Based on multi-body system theory, a geometric error model for the laser annealing table was established. It supports the identification of 7 geometric errors affecting the annealing accuracy. An original identification method was presented to recognize these geometric errors. Positioning errors of 5 lines in the workspace were measured by a laser interferometer, and the 7 geometric errors were identified by the proposed algorithm. Finally, a software-based error compensation method was adopted, and a compensation mechanism was developed in a postprocessor based on LabVIEW. The identified geometric errors can be compensated by converting ideal NC codes to actual NC codes. A validation experiment has been conducted on the laser annealing table, and the results indicate that positioning errors of two validation lines decreased from ±37 μm and ±33 μm to ±5 μm and ±4.5 μm, respectively. The geometric error modeling, identification and compensation method presented in this work can be straightforwardly extended to any configurations of 2-dimensional worktable.

Estimating network effects in China’s mobile telecommunications

A model is proposed along with empirical investigation to prove the existence of network effects in China’s mobile telecommunications market. Futhernore, network effects on China’s mobile telecommunications are estimated with a dynamic model. The structural parameters are identified from regression coefficients and the results are analyzed and compared with another literature. Data and estimation issues are also discussed. Conclusions are drawn that network effects are significant in China’s mobile telecommunications market, and that ignoring network effects leads to bad policy making.

Mechanical Characteristics of Chemically Degraded Surface Layers of Wood

The aim of this research was to find out whether the effect of chemical corrosion changes mechanical characteristics of surface layers of wooden construction elements. Degradation of the surface layers of wood was caused by chemical reactions of the basic substances of wood mass with compounds contained in antifire coatings. Fire retardants containing corrosive substances were often and repeatedly used in the Czech Republic on many wooden building constructions. This process of chemical corrosion is in practise called as ＂surface defibering of wood＂. This contribution presents standard and special experimental methods used for measuring the selected mechanical characteristics （compression strength, tension strength, bending strength, hardness and impact resistance） in the damaged surface layer of wooden construction elements. The material for experimental measuring was a construction element removed from a historical roof （ca 150 years old）. Mechanical characteristics of the surface layer of the defibered element were compared with the values measured in the deeper subsurface layer of non-damaged wood. The results of the experiments proved loss of cohesive strength and decrease of mechanical characteristics of wood only in a thin surface layer.

Agroforestry Initiatives for Capacity Building and Social Security through Captive Plantations on Degraded Lands of Farmers in State Karnataka, India

To meet the demand of raw material, i.e., wood, from the available sources always remained a big challenge for paper industries since the last two decades. For a sustainable supply of raw material in future, major plantation activities were undertaken by paper industries, like West Coast Paper Mills Limited （WCPM）, by constituting a society, i.e., Society for Afforestation, Research and Allied Works （SARA）, Dandeli in 2001. The main aim was to promote afforestation programme through major plantations activities on the degraded lands （under rainfed condition） and to generate employments and capacity building. The WCPM is a leading paper manufacturing industry of the country （under the flagship of Bangur group） located at the bank of Kali River in Dandeli of Uttar Kannada district in State Karnataka. To date, company through SARA has raised captive plantations on more than 50,000 acres of degraded land by farmers in different districts of Maharashtm, Karnataka, Andhra Pradesh and Tamilnadu States under Captive Plantation Project through Contract for Farming （CFF） since 2006 under a simple agreement period of only five years. After five years, society arranged to harvest the first rotation crop of the farmer of 2006, 2007, 2008, 2009 plantations and paid the amount of the crop directly to farmers. SARA has a mutual contract with WCPM for purchasing pulpwood. With this, farmers are getting full amount of their crop harvested after five years without any hurdle through SARA. SARA did all the expenditures, i.e., from land development, plantation and harvesting. Under its agroforestry plantation programme, superior planting material of various pulpwood species suited to particular area, i.e., Eucalyptus, Subabul, Casuarina and Acacia were planted on farmer＇s land. Farmers were also encouraged for intercropping, like maize, peanut （groundnut）, chilly, tomato and ginger with plantations. Apart from this, SARA is also providing free fodder to the livestock of farmers. Various types of fodder species such as Stylosanthes scabra, S. hamata are grown with plantation. SARA has also set up its own hi-tech clonal nursery developing around 5-6 millions of clonal ramets every year through clonal propagation technology. Till date, SARA has received 0.15 million ton （MT） of pulpwood from the plantations on farmer＇s land with a yield of 25-30 MT/acre. This type of activities will prove a boon for farmers as well as for industry, when raw material is going to be short in India. It will also conserve our natural resources, high conservative valued forests （HCVF） and will reduce the pressure on forest for wood. In addition, this will maintain the balance between environment and nature. To meet the requirement of pulpwood for industry, this type of plantation activities will open new ways for industry to secure raw material for future use. Also, this would be helpful to enhance productivity and generate employments for rural communities to improve their living standard and capacity building.

Preliminary Data on Legionella Detection in Water Distribution Systems in Cameroon

After the declaration of the first case of Legionnaire＇s disease in Cameroon in 2007, the Centre Pasteur of Cameroon implemented the detection method for Legionella. The introduction of this new method was put in places in order to investigate Legionella spp. colonization of water distribution systems （WDS） of large buildings including hospitals, hotels and Off Shore Exploitations Sites （OSES） in an attempt to identify risk factors for Legionella spp. Water systems of 6 hotels, 6 hospitals and 6 ships were investigated for the presence of Legionella spp.. A total of 130 samples were collected, 77 from hotels, 27 from hospitals and 26 from ships. 51 Legionella spp. were isolated from 41 （31.54%） water samples. Of a total of 51 positive isolates, 40/51 （78.4%） were L. pneumophila with 21 （52.5%） Legionellapneumophila serogroup （sg） 1, 16 （40%） L. pneumophila sg 5, 2 （5%） L. pneumophila sg 6, 1 （2.5%） L. pneumophila sg 7 and 11/51 Legionella spp. with 10 （90%） L. anisa, 1 （10%） Legionella dumoffii. 5 L. pneumophila sg 1 were associated with 5 L. pneumophila sg 5 and 4 L. pneumophila sg 1 were associated with 4 L. anisa. These results showed that WDS of hospitals, hotels and ships can be heavily colonized by Legionella spp. and may present a risk of Legionnaires＇ disease. Based on these preliminary results, we have just put in place a Legionella survey protocol in Cameroon.