Advanced Materials Research Vols. 368-373

Abstract: This paper studies the High strength and high performance concrete that is suitable for the steel reinforced concrete. In the basis of meeting the durability, strength, workability and volume stability, the mix proportioning of high strength and high performance concrete is optimized in the aspect of engineering cost . By experiments, minimum range of mix proportioning is defined which can meet the requirement of the every performance of high strength and high performance concrete, constraints are given, then, mathematical model of the optimization design for mix proportioning of high strength and high performance concrete is determined. Linear optimization problem is solved by MATLAB programming. Optimization example shows that optimization approach is feasible and effective in the paper.

Abstract: In order to get mechanical properties and anti-explosion capability parameters, some RPC samples with 5% steel fiber are tested, many groups data were obtained such as compressive strength, shear strength and fracture toughness. The model tests are also carried out on RPC shelter plate under contact explosion, the most important parameter to express anti-explosion capability,i.e. compression coefficient of the material, is obtained by above experiments and theory study, the results of tests show RPC with steel fiber has very high strength and anti-explosion capability, its compressive strength and anti-explosion capability are about six and three times higher than those of C30 concrete respectively.

Abstract: By using finite element software ABAQUS, the nonlinear finite element analysis of earthquake resistance behavior of L-shaped concrete-filled rectangular composite steel tubular columns is carried out, furthermore, the analysis results and the corresponding experimental results are compared. The results indicate that the finite element calculated value of ultimate bearing capacity is less than experimental value; axial compression ratio of the specimen has little affect on its ultimate bearing capacity and earthquake resistance behaviors; the results of FEM analysis can match the experiment results better, and thus, it can better reflect the earthquake resistance behaviors of the specimens.

Abstract: The construction technology and fundamental principle of a new kind of cast-in-situ reinforced concrete biaxial hollow slab with property of thermal-insulating is proposed in this paper. Compared with ordinary floor, the biaxial hollow slab is well load-carrying capacity in two-direction, light weight and thermal -insulating property.

Abstract: On the basis of five prototype top storey T-joints in R.C. frame structure with special-shaped columns, this paper examines shearing characteristic and mechanism. Based on the theory of softened strut-tie, the formulas for shearing strength of top story exterior joints in R.C. frame structure with special-shaped columns are derived. Three calculations are given in this paper, which are theoretical calculation, technical specification calculation and experimental value. The theoretical calculating value is compared with the testing results and the analysis shows that the technical specification formula can ensure high safety.

Abstract: Compacted soil-cement pile possess the excellences both flexible pile and rigid pile. The composite foundation of compacted soil-cement pile are getting more and more applicable to construction． However, the research on their response under dynamic load, especially under earthquake load，is quite limited．Now the seismic response analysis in time domain is performed with finite element method(ABAQUS).Some parameters influencing the anti-seismic behavior of half-rigid pile composite foundation are studied． Based on these research , some conclusions which may be of some value for anti-seismic design of this type of composite foundations are drawn．

Abstract: With the rapid development of inland wind farm in China, the costal wind farm still has not got large-scale development as the result of the higher cost of fan foundation and the more difficulty of construction. The prefabricated prestressed cylinder foundation (PPC foundation), as a new type of wind turbine foundation designed for the soft soil region such as the inter-tidal coastal zone and inland wetlands, is introduced in this paper. The condition of lateral earth pressure distribution around the foundation which determines the flexural capacity of fan foundation in the soft soil is studied. Through theoretical analysis and mathematical derivation, the result shows that the lateral earth pressure around PPC foundation is changed with depth by 1.5th power curve which has good fitting to the finite element analysis result. The simplified and improved design process is applied into the practical engineering and the good economy of PPC foundation is proved.

Abstract: The development of raft foundation design guide (RFDG) used in the high-rise building was programmed based on the secondary development language of ANSYS, such as TCL/TK, APDL and UDIL. The RFDG program provides a friendly GUI, which can be used expediently for the numerical experiment. The settlement analysis of raft foundation in the case study was carried out by RFDG. At the same time, the main technique for the secondary development of ANSYS has also been discussed in this paper.

Abstract: As FRP composite has a series of advantages such as higher strength weight ratio , higher rigidity weight ratio ,erosion resistance , no magnetism and high durability , it has being widely used in civil engineering ,its main characters and applications in geotechnical engineering are introduced in this article.

Abstract: This paper presents the experimental and numerical results of the ultimate bearing capacity of partially overlapped tubular N-joints, which have circular hollow section (CHS) brace members welded to a square hollow section (SHS) chord member. Two partially overlapped N-joints were tested to failure under overlapping brace axial loading and chord axial loading. The failure mode of specimen N1 was the overlapping brace local bucking, and the failure mode of specimen N2 was the chord face plastification with chord side wall buckling. Meanwhile, weld fracture occurred on both specimens. Then, making use of finite element package program ANSYS, in which twenty nodes solid element was employed and the weld was simulated, elastic-plastic large deflection finite element analysis of the experimental joints was conducted. The experimental data were compared with the results acquired by finite element analysis and it was proved that ANSYS is feasible to simulate the connecting weld and analyze the static behavior of partially overlapped CHS-to-SHS welded N-joints.