The aim of this study is to analyse the effect of temperature on the biodegradation and settlement properties of municipal solid waste by using bioreactors. Three kinds of controlled temperature were performed during the biodegradation test; the variation of weight, leachate and biogas production were carefully monitored. The degradation test indicated that more leachate leaked out owing to the external compression and polymer hydrolysis reaction in the aerobic phase, which could lead to the decrease of biodegradation rate in the anaerobic phase. A proper temperature range in favour of enhancing biodegradation of refuse was obtained, which ranged from 22 °C to 45 °C. Finally, an empirical equation of biodegradation ratio was proposed, which incorporated the temperature effect. In the end, the validation of this proposed model is verified, and is proved to be reasonable for predicting degradation velocity in landfills.

The forces on TBM druing tunnelling are analyzed in detail based on the characteristics of mixed face strata. Suitable parameters of TBM are choosed according to the characteristics of the strata ahead. The studies are focused on both the acting posture of TBM and the points of the main forces. A systemic model is consequently set up, which can provide ones with analysis of TBM stability, parameter calculation and tunnelling design in mixed strata. Two cases are finally analyzed of TBM tunnelling in different mixed strata by using this model. Then some of countermeasures is given as reference for TBM tunnelling in such mixed strata in the further.

The mechanical properties of artificial frozen soils are the key for application of artificial ground freezing, (AGF) especially the creep characteristics of artificial frozen clay when a deep shaft is sunk by using AGF. Many catastrophic accidents took place in clay strata in deep freezing shafts past because of freezing tube breaking and flooding through ice wall caused by large creep deformation of ice wall. A new creep constitutive equation with separated variables for artificial frozen clay, after C. C. Vialov, is presented on base of testing data of most kinds of artificial frozen clay under the condition of drained system. On base of the new equation, a space-time- dependant design method, a modified C. C. Vialov’s, is proposed and has been successfully used for ice wall of deep shafts all over China since 1996. Finally, the stability of ice wall for deep shafts can economically and efficiently be controlled by adjusting the variables of temperature T, un-supported height h and time elapsed t according to their sensitivity or influence.