This technical report on the compression behavior of soft soils in the Colombian capital, Bogotá, was conducted because the city’s recent construction history has led to excessive settlement of soils in the city over the last forty years. Several studies have shown the city’s soil to contain unusually high concentrations of diatoms. The stationary piston method was used to obtain samples from depths of between five and 100 m. Samples were subsequently examined in the laboratory, being subjected to triaxial and oedometer compression tests, and tested also for Atterberg limits and grain size distributions. Test results for undisturbed soil returned very high liquid limit values, compressibility indices C_C, secondary compression coefficients C_α, and soil structure effects. Some samples showed particle mixtures of different sizes, mineralogy, and diatom concentrations. Although high C_C and C_α indices explain the excessive settling of the city’s buildings, most construction projects do not currently take settlement caused by secondary compression into account. This report shows that secondary compression is an important parameter in the total settlement of buildings in Bogotá and that, furthermore, settlement is also affected by geological history. Finally, useful correlations such as the relationship between the liquid limit, C_α and geological history are presented.

这份关于哥伦比亚首都波哥大软土压缩行为的技术报告之所以进行，是因为该市最近的建设历史导致该市在过去四十年中土壤过度沉降。几项研究表明，该市的土壤中含有异常高浓度的硅藻。固定活塞法用于从 5 到 100 m 的深度获取样品。随后在实验室对样品进行检查，进行三轴和 oedometer 压缩测试，并测试 Atterberg 极限和晶粒尺寸分布。原状土的测试结果返回了非常高的液体极限值、压缩指数C _C、二次压缩系数C _α, 和土壤结构效应。一些样品显示出不同尺寸、矿物学和硅藻浓度的颗粒混合物。虽然高C _C和C _α指数解释了城市建筑物的过度沉降，但目前大多数建设项目并未考虑二次压缩引起的沉降。该报告表明，二次压缩是波哥大建筑物总沉降的重要参数，此外，沉降还受到地质历史的影响。最后，给出了有用的相关性，例如液限、C _α和地质历史之间的关系。