Abstract:On the basis of the soil mechanics theory, the changes of stress and shear strength after grouting process are disclosed, and relevant conclusions are made by analysing the action of grouting process on the structure of foundation, physico chemical properties, etc

Abstract:The description is made of the key technical points of the foundation pit support construction, including pile wall, cement soil, anchor, diaphragm wall, combined bolting and shotcrete (soil nail), with each support structure analyzed in regard to its field case

Abstract:This paper discusses the relationship between some important technical index and the quality index of bored piles, and presents some index control values for easy field use, the post survey method, as well as new methods and concepts concerning concrete groutability

Abstract:In conjunction with its use at the Changjiang main dike, the concrete leakage cut off wall construction technique using the water jetting method is described in terms of the construction conditions, machinery, and effects Proposals on the promotion and the improvement of the technique are put forward

Abstract:This paper describes briefly the testing and measuring system, data aquisition system, main technical properties and parameters and main equipment of the testing bench, development of the testing device, and effects of the computerised automatic data aquisition

Abstract:The paper uses a modified theoretical model and a modified spring model to establish the calculation model of load distribution under make up torques and axial loads by analyzing the load condition of the drill collar Law of load distribution has been analyzed in detail The effect of thread taper, frictional coefficient caused by different lubricants and spring coefficient of the thread on load distribution of the threaded connection have been pointed out In addition, some main measures for improving the load condition of the connection and reducing the stress concentration are presented The maximum axial load of connection has also been obtained by a simple mechanical model

Abstract:The article introduces a model about sensor integration for twist drill condition monitoring and fault diagnosing In the model,the sensors are: force sensor, acoustic emission sensor and temperature sensor, and the methods of fault diagnosis are artificial neural network, fuzzy diagnosis and grey relation diagnosis

Abstract:The service life of the coated tool can be extended through the improvement of the bonding force between the diamond film and the tungsten carbide base The experimentation results show when the diamond film is deposited on the surface of tungsten carbide preplanted with diamond micro powder, not only will diamond grow outwards on the surface of the preplanted diamond in a homogeneous manner, but also grow on tungsten carbide through crystallization, which takes place alternately and exhibits good compatibility, resulting in a dense and uniform diamond film

Abstract:The new PDC cutter that has a tungsten carbide surface layer can keep the self sharpening characteristics and aslo avoid the breaking off phenomenon of the PDC cutter Results from testing show that the new PDC cutter has better performance than the conventional PDC cutter in terms of drlling rate, strength and durability in hard rock drilling

Abstract:The paper discusses the surface boronization method and technology used in the experimental research of hard alloy bits It has a positive effect on the improvement of hard alloy bit body surface strength, wearability and service life

Abstract:The preliminary study has been conducted on the drill string testing technology, including mainly the determination of the drill string testing parameters, selection of the testing method, the preliminary testing plan design, etc.

Abstract:The construction character, the selection of drilling equipment, drilling technology, drilling mud technology and well completion for infill drilling of thick oil well are presented with drilling cases introduced

Abstract:The phenomena of rock fragmentation by blasting is studied through the scanning electronic microscope and the fracture mechanism of rock is also discussed

Abstract:Box Culvert Jacking is a kind of large section and short span trenchless technique The advantages include less disturbance to environment, short construction period and lower cost Its social benefits and economic benefits are eminent In order to protect the Ancient City Wall, box culvert jacking is used to cross the foundation of the Ancient City Wall This paper discusses the structural design and prospect of the box culvert jacking technique

Abstract:Small duct advance grouting and grouting material, as well as the determination method of grouting parameters are described in detail with the underpass construction case