A long term resilient modulus rate dependent model for coarse fine mixtures geomaterials under freezing and thawing cyclic.

The cyclic loading frequency (f) effects on the resilient modulus (M) of freezing-thawing coarse-fine mixtures geomaterials (FTCFG) have always been a research hotspot. A series of long-term cyclic triaxial tests were conducted on FTCFG having different fines content (FC) under different number of freeze-thaw cycles (N) to investigate the effect of f and deviator stress amplitude (q) on the M of FTCFG. The freezing-thawing cyclic was found to improve the M of FTCFG.

An Empirical Dilatancy Model for Coarse-Grained Soil under the Influence of Freeze-Thaw Cycles.

In the era of high-speed trains, it is very important to ensure the safety and stability of rail tracks under adverse conditions including seasonal freezing and thawing. Freeze-thaw cycles (FTCs) affecting the engineering performance of coarse-grained soil (CGS) is one of the major reasons for track deterioration. The reported results of a number of static freeze-thaw triaxial tests on the shear behaviour of CGS are analysed herein.

Experimental Study on the Compaction Characteristics and Evaluation Method of Coarse-Grained Materials for Subgrade.

Coarse-grained materials are widely used in high-speed railway construction, and it is of great significance to research its compaction characteristics due to the high quality control requirements. In this regard, a field compaction experiment was conducted at a subgrade near Bazhou Station of Beijing-Xiong'an Intercity Railway. The test results of the compaction effect were presented in this study at first.

Evolution of Rheological Behaviors of Styrene-Butadiene-Styrene/Crumb Rubber Composite Modified Bitumen after Different Long-Term Aging Processes.

In this study, a new type of composite modified bitumen was developed by blending styrene-butadiene-styrene (SBS) and crumb rubber (CR) with a chemical method to satisfy the durability requirements of waterproofing material in the waterproofing layer of high-speed railway subgrade. A pressure-aging-vessel test for 20, 40 and 80 h were conducted to obtain bitumen samples in different long-term aging conditions. Multiple stress creep recovery (MSCR) tests, linear amplitude scanning tests and bending beam rheometer tests were conducted on three kinds of asphalt binders (SBS modified asphalt, CR modified asphalt and SBS/CR composite modified asphalt) after different long-term aging processes, including high temperature permanent deformation performance, resistance to low temperature thermal and fatigue crack.