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the construction method of the ordinary cemented soil stiffness core composite pile is that the pile peripheral cemented soil and the core pile are constructed at different time, which might lead to the situations as the pile body is broken due to the forced inserting of the core pile into the cemented soil mixed pile after the initial setting time, the neighboring finished pile is damaged due to the compacting effect caused by the reaming construction of the core pile and the failure of effectively transferring the load due to the loose joining of stiffness core pile and the cemented soil whose construction is completed after the initial setting time. This paper aims to overcome the defects of the conventional construction method by introducing a new construction technology, and the construction technology is verified to be reliable through the application in the actual engineering projects and has the advantages that the peripheral soil body is significantly strengthened, the composite pile foundation can effectively overcome the harm as uneven settlement of buildings, so as to ensure the normal usage of the buildings, and the construction technology has excellent economic benefits and is significant for the later construction technology for treating the soft soil foundation.

Guided by the high-resolution sequence stratigraphy theories, the authors divided the Upper Jurassic Penglaizhen Formation in the middle section of western Sichuan depression of china into 2 long-term sequences (L1-L2) and 4 medium-term sequences (M1-M4) through comprehensive study of outcrops, coring, logging and seismic data. Sequence-based lithofacies and paleogeographic maps of Upper Jurassic Penglaizhen Formation were compiled by medium-term sequences as mapping units. The results showed that the front edge of Longmenshan developed with large-scale alluvial fans, fan delta sediment was a fan-delta group overlapped by several fan deltas at front edge of Longmenshan in period M1-M4.The dominated type of sedimentary system in middle section of western Sichuan depression was fan delta - shallow lake sediment in period M1-M2, alluvial fan was only changed in size and location; sand bodies were mainly distributed in front edge of Longmenshan and the Zhongjiang-Deyang region; In period M3-M4, it is changed into a large area of fan delta plain sediment with thick sand and big scale, sand bodies were mainly distributed in the Pixian-Wenjiang-Dayi area.

When calculating compressive resistance reliability of gravity dam using the elasticity stochastic finite element method, as a result of stress singularity of dam toe, elements near the dam toe has been encrypted to different mesh size, find a point along the foundation plane that its compressive resistance reliability index is not sensitive to mesh and it is nearest to the dam toe, select the compressive resistance reliability index of the point as the compressive resistance reliability index of gravity dam. Take Longtan RCC gravity dam as an example and give the analysis results.

According to the existing arch dam design specification, the temperature load is obtained based on analytic solution of infinite long free plate, it only considers the average temperature and the equivalent linear temperature difference of dam section in operation period, the influence of non-linear temperature difference has not been considered. This kind of simplification has some approximation; especially it can not reflect spatial effect of larger temperature gradient changes in the upstream and downstream water level change area. This paper first takes the free plate as an example, has calculated the temperature field corresponding to analytical method, finite element method, standard method, explains the rationality of using written program to carry on finite element analysis. On this basis, take Xiluodu arch dam as an example, the dam temperature load and temperature stress has been analyzed by using finite element method and standard method, the difference between both has been discussed