2014 Vol. 28, No. 6

Development and Creation
The Common Security and Control Key Point of Deep Foundation Pit Proximate to Existing Buildings
Song Fuyuan, Hu Hexiang, Guo Heng
2014, 28(6): 271-274,295. doi: 10.3969/j.issn.1007-2993.2014.06.001
Abstract:
The text carries out comprehensive and in-depth analysis on the common security problems of deep foundation pit construction neighboring to the existing buildings, puts forward the deep foundation pit's safety control points during construction, provides a solution for the safety and smooth implementation of similar foundation pit engineering.
Analysis of Application Prospect of GFRP Bar in Excavation Engineering
Geng Yekuan, Fan Youwei, Jin Xuelian
2014, 28(6): 275-277. doi: 10.3969/j.issn.1007-2993.2014.06.002
Abstract:
Base on characteristic of high tensile strength, poor shear capability, light and environmental protection, it analyses the application feasibility of GFRP bar in excavation engineering, clarify the scope of its application in excavation engineering, sum up the problems of excavation engineering application of GFRP bar, which provides solutions, and it's useful for application and development of technology of geotechnical engineering and new materials.
Practice in Design and Construction of Oversized Deep Foundation Pit Project in Beijing
Jiao Shenhua, Wang Jinan
2014, 28(6): 278-282,315. doi: 10.3969/j.issn.1007-2993.2014.06.003
Abstract:
Along with the needs of development of underground space, engineering of foundation pit, which is the technical support for underground development, is facing new challenges. This arlicle reviews the characteristics as well as design scheme of shallow foundation pit projects in Beijing area and analyzes tile features and challenges of urban oversized deep foundation pit projects. Combined with design, construction practice, monitoring as well as evaluation of an oversized deep foundation pit project in Beijing, the design concept of oversized deep foundation pit project is summarized and new ideas for development of foundation pit in Beijing area are raised.
Technology Probe and Research
Existing Problems and Improvement Direction of High-strain Dynamic Testing Technique to the Testing of Pile
Sun Xiaogang, Chen Defa
2014, 28(6): 283-286. doi: 10.3969/j.issn.1007-2993.2014.06.004
Abstract:
As a simple, cheap,and relatively accurate method,high-strain testing technique to the testing of pile has been generally accepted and widely implemented. However,there are still many limitations and shortcomings no matter in hardware and in software. In order to promote development and perfection,give better service to the construction requirements, based on thorough analysis, the latest developments in technology are introduced by author through extensive investigation at home and abroad.
Detection and Analysis of Effect of Strengthening the Sandy Soil Foundation by Dynamic Compaction Method
Wu Xinghui, Men Qingbo, Chang Yujuan
2014, 28(6): 287-290. doi: 10.3969/j.issn.1007-2993.2014.06.005
Abstract:
For lack of detection and analysis of effect of strengthening the sandy soil foundation by dynamic compaction method in situation, with the actual example in the project in this paper, using a variety of methods for detection and contrastive analysis of strengthening the sandy soil foundation between some dynamic compaction method and natural sand, evaluate objectively the effect of strengthening the sandy soil foundation by dynamic compaction method and discuss the factors influencing reinforcement effect. This research has accumulated experience for detection of reinforcement sand soil foundation by dynamic compaction method, and has important value and significance for improving application in the design, construction of dynamic compaction method.
Application of Ground Penetrating Radar Detection in Diseases of Ancient Wall
Luo Huiguo, Zhang Qingli, Niu Zhifei
2014, 28(6): 291-295. doi: 10.3969/j.issn.1007-2993.2014.06.006
Abstract:
Due to the rain and snow erosion for years, the ancient wall is likely to cause lots of diseases area such as loose of brick layer and soil of internal walls, but it is a difficult problem to determine the location of these diseases, depth, size, etc. Ground penetrating radar as a non-destructive means of detecting, has features of high efficiency, high resolution, intuitive results of the detection target without causing any damage. In this paper, combined with engineering examples, using ground-penetrating radar technology to detect the ancient wall top surface. According to the processing and analysis information of GPR,selecting five representative of the radar map to carry out rod detection. Combined with the information of rod detection, carried out a comprehensive analysis to improve the accuracy of finding out disease areas, indicating the usefulness in ground-penetrating radar to detect the ancient wall.
Research of the Tunnel and Dewatering Technology under Complicated Environment Conditions
Song Keying, Feng Keming, Ma Jian
2014, 28(6): 296-299. doi: 10.3969/j.issn.1007-2993.2014.06.007
Abstract:
City center metro dense buildings need to make a long distance through the existing building (structure), resulting in ground tube well construction and more difficult operating conditions, precipitation, sedimentation control requirements have become more stringent. In this paper, starting from the rail transit construction, when restricted by the construction site, construction of tube wells proposed in the guide hole, and precipitation guide hole design, as well machinery and construction method are discussed. For additional settlement construction precipitation caused by the use of three-dimensional groundwater flow model coupled with land subsidence calculation software——Processing Modflow, establish coupling model of groundwater flow field and land subsidence, according to the on-site monitoring data, the model parameters using the modified, different designs pumping down the program, scheduled settlement prediction conduct timely analysis of the impact of construction on the surrounding environment of precipitation, and can guide a similar construction, the project has an important practical significance.
Design and Construction of Underground Drainage in Fractured Rock Region
Shao Guanhui, Liang Henghui, Yuan Kuanyao
2014, 28(6): 300-303,310. doi: 10.3969/j.issn.1007-2993.2014.06.008
Abstract:
During the work of buildings or roads in fractured rock or adequate groundwater region,water seepage is the main factor affecting the construction, especially in the rainy season. The lack of underground drainage facilities will directly affect the construction and road usage performance, reduce its service life and seriously affect operational safety. Taking an underground metro park in Wuxi as a research object, this paper systematic studies the drainage solutions of the seepage area from the survey,design, construction and other aspects. It proposes different technical measures of structure foundation and embankment,emphasizes key points of construction quality control,which has application value in underground drainage system design for big construction in fractured rock region.
Study on Seepage Characteristics of Qingcaosha Levee Using Significance Tests
Ma Jun
2014, 28(6): 304-307. doi: 10.3969/j.issn.1007-2993.2014.06.009
Abstract:
Qingcaosha reservoir is located in the entrance of Yangtze river. The body and foundation of levee is con〉 posed of a large number of sand and silt. To ensure the safety of tile levee and master the levee seepage law, it needs the special researching on seepage characteristics of levee. The seepage testing of levee was respectively done in construction period of 2007 and operating period of 2010. Seepage parameter of the two periods was compared, and the seepage parameter of operating period was analyzed using significance tests of mathematical statistics. It supplied effective data for the studying of seepage deformation.
Analysis of the Processing of the Wasted Underground Air Raid Hole
Wang Rongjie
2014, 28(6): 308-310. doi: 10.3969/j.issn.1007-2993.2014.06.010
Abstract:
It is introduced in detail that the pressure grouting is used in the processing of wasted air raid hole,with its principles, methods, crafts, materials, test methods and the treatment effect, against the wasted air raid hole and its harm to the building safety. With concrete examples, the advantages of the method are described and the entire process of construction with its craft arrangements in detail. And this is helpful to the process of the wasted air raid hole in practice.
Silt Dynamic Triaxial Test Indicators to Determine
Zuo Hui, Zhang Liushuan
2014, 28(6): 311-315. doi: 10.3969/j.issn.1007-2993.2014.06.011
Abstract:
Yanshan Iron was designed for using open-pit mining with the maximum height Of the final slope 600m. The height of the slope made of Quaternary System layer is up to 40 m in the east,while it is up to 70 m in the west. It is a high slope. Upper slope is made of silt, silty sand, medium sand, gravel and clay, lower slope is made of sandy clay and gravelly clay. Measuring the changes in the intensity of silt and silty clay layer under the influence of earthquake is important for the slope stability analysis.
Damage Models and Formation Mechanism on Both Sides of the Mountain Slope of the “5 · 12” Wenchuan Earthquake
Han Lifang, Luo Bing
2014, 28(6): 316-319. doi: 10.3969/j.issn.1007-2993.2014.06.012
Abstract:
The Wenchuan earthquake unleash a host of geological disasters. The main case of the geological disasters of this slope are the same. Under seismic action, two different damage models appear on both sides of the ridge:high landslide and collapse. This paper analyzes the formation mechanism of these two geological disasters, basing on geological characteristics and deformation characteristics. Through the analysis of the deformation characteristics, further expounds the factors of two different geological disaster modes.
Analysis on Abnormal Construction Quality of Vibro-pile for Xiamen's Marine Soft Soil Foundation
Zhang Bafang
2014, 28(6): 320-323. doi: 10.3969/j.issn.1007-2993.2014.06.013
Abstract:
The abnormal qualities of vibro-pile of Xiamen typical marine soft soil foundation were detected respectively by the means of bearing capacity of pile testing and pile integrity testing. According to the characteristics of Xiamen's marine soft soil foundation and the construction technology of vibro-pile, the main influential factors of the quality for abnormal construction quality of vibro-pite were systemically analyzed. The results showed that the main quality problems of vibro-pile of Xiamen marine soft soil foundation were pile breaking and necking, and rational suggestions were taken for their solution.