The Research Of Half-Dry Concrete Rammed Cast-In Situ Pile Build With Weak Roadbed

In the past 50 years, the roadbed of operating railways in our country, espetially the surface layer of the roadbed, were build with fine grained soil. The dynamic loads of trains and the erosion of environments bring large accumulative settlements, even shearing destruction, to the roadbed. Only in Chengdu Railway Bureau, the roadbed disease exist in hundred of kilometers. Concerning the problems caused by weak roadbed build with Chengdu Clay at K337 to K338 in DaCheng-railway, the renovating plans were determined under the analyses to the structure and technical standard of the roadbed. Tests were carried out in-situ to obtain the data of the dynamic stress, dynamic displacement, acceleration and dynamic velocity. Through these data, the renovating effects of the rammed cast-in-situ pile built with half-dry concrete were present. This measeuremet can enhance the strength and the rigid of the roadbed, reduce the displacement of the roadbed and improve the dynamic characteristic of the roadbed. Furthermore statistic has been used to analyse these data. According to the comparison on the test data and the domestic and abroad research achievements, the evaluation and assessment of the engineering effect and social economy benefit to the rammed cast-in-situ pile built with half-dry concrete were made. Also, the suggestions to the application and spreading of this mesurement in the future are offered.