1998 No. Z1

Abstract:
Since the concrete defects are popular,the technology concerning detecting and repairing the defects takes an important role during the construction and operation of the dam engineering. On basis of a lot of technical literature home and abroad,the current development level and the technical characteristics of these technologies are discussed and reviewed in this paper.
Abstract:
The paper analyses the styles and reasons of the break in the concrete dams. Main reasons of four breaking styles (freeze-thaw, frozen heaving,cracks,corrosion and cavitation erosion) prove to be low grade of concrte strength,low resistance to freeze-thaw,low resistance to permeation,high temperature stress,and material selected and construction out of control. The paper introduces the repairing technique and the selection of repairing materals elaborately,according to the repairing practices of some concrete dams, such as Fengman, Yunfeng, Huanren,Shenwo and etc..
Abstract:
This paper presents the investigation results on the damaged reinforced concrete structures of coal transport wharf of BeiLun thermal power plant. The chlorion content of mortar samples, which dissociated from the structures in wave-splash area, is tested and analyzed. The deterioration causese of the structures are summarized, and a suitable strengthening scheme is introduced.
Abstract:
In this paper, the reasons for seepage of the expansion cracks are analysed. Then the aptching technology and methods arc Introduced,and finally the mechanical properties of the patching materials are presented.
Abstract:
The paper analyses the reasons and developing law of concrete temperature cracking.For two spectles of tempcrature stress crack1ng,treating methods and materials are preliminarily studied. Finally a few case histories in engineering practive are taken as examples.
Abstract:
This paper analyses the disadvantage of large volume concrete expansion joint and construction joint with the facts of Shenwo,Guanyinge Reservoirs. At the same time,it introduces the mending effects of choking up-draining down and regional seepage prevention. So that it can proveide a reference for the similar projects.
Abstract:
The penetrating crack is one of the defects in concrets structures,which threatens the safety,serviceabillty and durability of concrete structure. Effective mending of concrete defects is a question to be worth studing in engineering. According to a successful example of mending of concrete penetrating cracks,the program and method of mending are elaborated in this paper.
Abstract:
Between the bottom of the vertical shaft and the connected part of sluice gate chamber,there is a crack 11. sin in length and 2-20mm in width. We use chemical grouting to caulk it and reinforce structure by adhesion technology of steel plate. The methods get good results,and these buildings have been used for four years.
Abstract:
A new construct1on technique in repairing and strengthening dock wall under water is introduced in th1s paper. Some construction methods,such as foundation widening,rockfill foundation-bed,inverted filter and reinforccd concrete protecting wall,are discussed comprehensively.Indexes of physico-mechanical properties and application of subaqeous nonspreading concrete with CT20-2 anti-spreading agent are emphatically introduced.
Abstract:
This paper describes how to use the fixcable drown type floating operational platform and non-dispersible concrete to concrete a large area stncture at 20m water depth. The technique of underwater concreting is also applied to concrete the thin layer. According to the testing results,it is proved that the underwater concreting strength conforms with the design requirements and the pictures photoed under water indicate that the comcreting surface is rather smooth and the height satisfies our clients.
Abstract:
The barometric buoy was designed and made by Administration of Wanfu sluice of Jiangsu province. It can be used to repair works under water at a depth 2. 8-7.5in. The equipment have many good features. It has characteristics of low costs easy movement and drainage,and it is used widely in practice. It has been successfully used in Gozhouba Project, Wanfu sluice and so on large-scale water conservancy projects,which has made high social and economic effects.
Abstract:
This paper introduces how to repair two small dams by the use of repairing materials and improving construction. According to the analysis of two examples,a kind of repairing method is presented,which includes using gabion wrapped with plastic net as energy dissipator and choosing acrylic acid emulsion mortar as repairing material.
Abstract:
Accordance to the real present corrosion and deterioration conditions of steel structure and reinforced concrete plate in Linhong sluice, high build epoxy coating had been adopted to repair 26 gates from 1992 to 1997,the total protected area is 1965. 6m2. The gates are protected from the electrochemical corrosion and their durability is also imporoved. Some gates have been used well for more than 5 years,and quite good effects have been achieved both in technology and economic,and it has accumulated a wealth of experience in treating deterioration of hydraulic structures.
Abstract:
This paper introduces the technology process of using CT101 conpensating shrink agent in reinforcing and heightening the Tianshenggang seawall. Insitu measuring results indicate that the CT101 agent can effectively conjoin the old and new concrete together.The seawall has withstood the No. 11 typhoon in 1997. 8.
Abstract:
This paper introduces the basic functions of acrylic acid emulsion mortar. After comparing with other kinds of materials used to rapair concrete,the plan is made out to repair the spillway surface in Panjiakou dam. The Paper explains the repairing experience,incluing modifying the ratio,improving technology and management,and the good results have been achieved. Thin layer repairing also gets good results in the places where freezing,scouring and rubbing are forbidden.
Abstract:
In this paper, the methods of strengthening the girders in Doufuwo flood-diversion gate using acrylic acid emulsion motar have been summarized. Construction procedure and technology applied into repairing old concrete girders are studied and good effects have been achieved. The methods can be widely applied to strengthen concrete structures and prevent concrete from ageing.
Abstract:
The paper introduces the investigation result and repairing method of the ageing and disease of more than 130 culvert gates on the river courses in Beijing. The investigation indicates that the greatest menace to the reinforced concrete of these culvert gates is the peeling of the component surface and the rusting of reinforcing bar caused by carbonizationof the concretes, the area needed to be repaired rapidly is 40% of the survey area. The mending process on carbonated concrete of 17 culvert gates is also presented by using compensating systolic mortar and epoxy coating Hz902.
Abstract:
Protection principle of steel bar corrosion is researched comprehensively in reinforced concrete structure, the binding problem between the new and the old materials is discussed,and a new measures of protection and repair is put forward in the end.