期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
A comparative assessment of rock mass deformation modulus 被引量:3
1
作者 Kadir Karaman Ferdi Cihangir Ayhan Kesimal 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第5期735-740,共6页
Deformation modulus of a rock mass(E_m) is one of the most important design parameters in construction of rock engineering projects such as underground excavations.However,difficulties are frequently encountered durin... Deformation modulus of a rock mass(E_m) is one of the most important design parameters in construction of rock engineering projects such as underground excavations.However,difficulties are frequently encountered during in-situ tests which are also time-consuming and expensive for determining this parameter.Although E_m is often estimated indirectly from proposed equations by different researchers,many of these equations cannot be used in case of problematic rock conditions(thinly bedded,highly jointed rock masses,etc.) as high quality core samples are required.This study aims to explore more practical and useful equation for E_m estimation using Rock Quality Designation(RQD) and point load index values.Comparisons were made between available empirical equations and the proposed E_m equation in terms of the estimation capacity.Multiple comparison tests(ANOVA) showed that E_m can be reliably estimated using proposed equation especially at the preliminary stages of projects. 展开更多
关键词 Rock mass deformation modulus RQD RMR Q RMI point load index
下载PDF
Alternative Method for Concrete Structures Compressive Strength Estimation with Small-Scale Destruction
2
作者 Achfas Zacoeb Koji Ishibashi 《Journal of Civil Engineering and Architecture》 2011年第2期147-153,共7页
To estimate a compressive strength from existing concrete structures by core drilling are usually gathered with a diameter specimen of 100 mm or three times of maximum coarse aggregate size and examined by uniaxial co... To estimate a compressive strength from existing concrete structures by core drilling are usually gathered with a diameter specimen of 100 mm or three times of maximum coarse aggregate size and examined by uniaxial compressive strength (UCS). It is relatively difficult to gather a large sized core, and a pit place will be limited by main members. To get an alternative solution with smaller specimen, point load test (PLT) has been sele,:ted which is a simple test and widely accepted in rock materials research, but relatively new in concrete. The reliability of PLT is evaluated by extracting a lot of core drilled specimen from ready mixed concrete blocks with maximum coarse aggregate size, G of 20 mm in representative of architectural structures and 40 mm in representative of civil structures on the range of concrete grade from 16 to 50. Compressive strengths were classified into general categories, conversion factors were determined, and scattering characteristics were also investigated. The relationship between point load index (Is) and compressive strength of concrete core specimen (fcc) can be written as linear approximation as fcc = k.Is- C. 展开更多
关键词 Strength estimation small core point load index linear approximation.
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部