In drilling cobble and gravel formation, diamond enhanced tungsten carbide composite spherical crown button bits without strengthened gage achieve an average drilling rate of 2.

On the foundation of analyzing cobble and gravel s physics and mechanics characteristics, we took them as foundationpadding layer and applied them in engineering.

Application of diamond enhanced tungsten carbide composite button to gravel formation;

Grain size survey of gravels in the section from Military Museum to Baiduizi for the programming Line No.9 of Beijing Metro

When small powered rotary rigs drill in mudstone,shale and big particle gravel with a diameter of 1,500mm for bored piles, the conventional inserted rock screw bits often present themselves slow penetration or even no penetration due to the rig s small power and small WOB.

Research on bearing capacity behavior of precast concrete piles in gravel stratum;

This paper presents the application of displacement back analysis for the tunnel engineering in gravel-cobble stratum taking the loosing zone into consideration.

Field test study of methods for supporting large-section inclined shaft in gravel layer

From consolidating similar past case studies with regards to the problems encountered during construction phase, this article is able to provide an important point of view on shield tunnel design in gravel layer.