Under reciprocating loading , the interaction relation of pile and earth are influenced by circulating frequency, the way of load addition, stress route and other.

In combination with the work of < the design and technical construction rules of flexible dolphin pier in port engineering > of designing institute of water transport of transport, the data of some typical experiments of domestic and international pile foundation were analysed emphatically. Through comparion of the relation of P-Y curves between single pile and pile group under lateral loading and lateral reciprocating loading , the experience formula of P-Y curve of single pile under reciprocating loading role is put forward.

Study on deformation behaviours of soil under slow reciprocating loading is not often seen but in practical engineering there are many examples of such case.

Consolidated drained triaxial tests are conducted for the saturated sand under slow reciprocating loading by the advanced GDS stress path triaxial apparatus.

In the nonviscous prestressed concrete framed structure there is a relative slide between the prestressed bar and the concrete wall owing to the reciprocating load,leading to the production of dissipated energy and additional stress.

1. Research of eonstitutive relations of concreteBased on the research of nonlinear elastic theory and elastic梡lastic theoryof constitutive relations of concrete and the hysteresis characters of concreteunder reciprocating load , the author proposes a scientific description of thedegeneration phenomena of the modulus of elasticity of the concrete that occurredalong with the development of deformation, in which the differential equationexpressing the relation between the degree of degeneration and the deformation ispresented.

Finally , aconstitutive relation model of concrete in the state of multi梔irectional stressunder reciprocating load is proposed as an extension of that in the case of singledirectional stress.

The characteristics of load versus deformation hysteretic curve including bearing capacity, skeleton curve and energy dissipation are presented and discussed.

To model characteristics of soil deformation and pore water pressure development under cyclic loading a boundary surface model was used which can model plastic deformation under low level of stress． The elastic unloading was replaced by elastoplastic process then a boundary surface form of generalized plasticity theory was presented． Experimental data and numerical simulation result have good agreement．

In this paper, the experimental results on full scale masonry walls with reinforced concrete tie-columns subjected to lateral reversed loading are presented. The formulae for calculating the lateral load bearing capacity and stiffness of such structure are suggested and a more rational model of hysteretic characteristic is developed.The nonelastic responses of two typical masonry buildings with tie-columns have been statistically analyzed by using a set of artificial accelerogramms. The regularity of required...

In this paper, the experimental results on full scale masonry walls with reinforced concrete tie-columns subjected to lateral reversed loading are presented. The formulae for calculating the lateral load bearing capacity and stiffness of such structure are suggested and a more rational model of hysteretic characteristic is developed.The nonelastic responses of two typical masonry buildings with tie-columns have been statistically analyzed by using a set of artificial accelerogramms. The regularity of required ductility distribution in stories along the height of building has also been studied. The value of structural influence coefficient C is found to be a little smaller than that given in the current aseismic code for masonry structure in general.

During the Tangshan Earthquake in 1976, there were events of soil liquefactions in the silty sand deposits on banks of Haihe River. In order to study the liquefaction behaviour of these deposits, saturated sand specimens are prepared in lab in the dry volumetric weight of the undisturbed samples and examined under cyclic loading for the cyclic shear resistance, pore pressure, and the residual shear strain developed.Tests are accomplished by means of a cyclic simple shear test apparatus developed in Nanjing Hydraulic...

During the Tangshan Earthquake in 1976, there were events of soil liquefactions in the silty sand deposits on banks of Haihe River. In order to study the liquefaction behaviour of these deposits, saturated sand specimens are prepared in lab in the dry volumetric weight of the undisturbed samples and examined under cyclic loading for the cyclic shear resistance, pore pressure, and the residual shear strain developed.Tests are accomplished by means of a cyclic simple shear test apparatus developed in Nanjing Hydraulic Research Institute. Test results are expressed in the relations of cyclic shear resistance, pore pressure, dynamic shear modulus and residual shear strain with number of cycles, vertical consolidation pressure, initial and cyclic shear stresses etc.

The experimental investigation results of earthquake resistant behaviour on 1/2 scale brick walls strengthened by additional reinforced concrete columns with steel tie rods under lateral repeated loading are presented in this paper.Three failure modes with corresponding formulae for calculating lateral load bearing capacities and stiffnesses of such strengthened walls as well as their hysteresis loop models are developed based on failure mechanism of specimens. Comparison of calculating results with testing...

The experimental investigation results of earthquake resistant behaviour on 1/2 scale brick walls strengthened by additional reinforced concrete columns with steel tie rods under lateral repeated loading are presented in this paper.Three failure modes with corresponding formulae for calculating lateral load bearing capacities and stiffnesses of such strengthened walls as well as their hysteresis loop models are developed based on failure mechanism of specimens. Comparison of calculating results with testing data shows that the calculating methods suggested in this paper can be used in practice. .