Showing papers by "Jian Zhao published in 2007"
TL;DR: The Kranji tunnel is part of the Deep Tunnel Sewerage System in Singapore as discussed by the authors, and two EPB TBMs were deployed at this tunnel with a bored diameter 4.90 m.
178 citations
TL;DR: In this article, the ratio of uniaxial compressive strength to Brazilian tensile strength was adopted to quantify the rock brittleness, which is one of the most important rock properties.
151 citations
TL;DR: In this paper, a series of TBM shield friction tests were conducted in a TBM tunneling site and the muck sieve analysis results verified that with increasing thrust force, muck size increases and the rock breakage efficiency also increases.
107 citations
TL;DR: The Web of Science Record was created on 2007-09-24, modified on 2016-10-14 by as discussed by the authors, with the purpose of generating a record for the first time.
98 citations
TL;DR: In this article, the authors examined the feasibility of employing the new generation fibre optic and piezoelectric sensor systems for comprehensive monitoring of rocks, covering load history monitoring/retrieval as well as damage assessment.
63 citations
Journal Article•
TL;DR: Wang et al. as discussed by the authors used a hybrid LS-DYNA and FLAC3D scheme to study the damage zone size of rock mass under blasting, and the numerical simulation results agree well with the site monitoring results.
Abstract: Sonic wave tests have been conducted in the construction site of Ling'ao Nuclear Power Station(LNPS)in Guangdong Province,China.Based on the change rate of sound wave speed before and after blasting,damage zone size of surrounding rock has been determined.On the other hand,a statistics-based damage variable of rock mass has been proposed based on micromechanics.Damage zone size of rock mass under blasting is thus studied using a hybrid LS-DYNA and FLAC3D scheme.It is reported that the numerical simulation results agree well with the site monitoring results,and the damage threshold for the rock in site of LNPS,Dc ri,is 0.2.The variation of damage zone size with charge weight has been analyzed by numerical simulations.It is observed that the rock damage zone size increases with charge weight.Damage zone depth of rock mass under blasting is less than damage zone radius.The damage zone radius is approximately 3 times of the damage zone depth.
4 citations
Journal Article•
TL;DR: In this article, the cracking initiation mechanism and extending process of intermittently jointed rock mass were simulated using software RFPA~(2D) and the results showed that the strength of the rock mass increases when the joint angles changed from 30°,45° to 60°, the deformation increases and the sound emission boosts up in the prophase of the failure.
3 citations
01 Nov 2007
1 citations
TL;DR: In this paper, the maximum peak particle velocities (PPVs) were compared with the field records, and the predicted PPVs from the proposed prediction model for the maximum rebound ratio match the field-recorded PPVs better than those from two empirical formulae.
Abstract: The proposed prediction model for estimating the maximum rebound ratio was applied to a field explosion test, Mandai test in Singapore. The estimated possible maximum peak particle velocities(PPVs) were compared with the field records. Three of the four available field-recorded PPVs lie exactly below the estimated possible maximum values as expected, while the fourth available field-recorded PPV lies close to and a bit higher than the estimated maximum possible PPV. The comparison results show that the predicted PPVs from the proposed prediction model for the maximum rebound ratio match the field-recorded PPVs better than those from two empirical formulae. The very good agreement between the estimated and field-recorded values validates the proposed prediction model for estimating PPV in a rock mass with a set of joints due to application of a two dimensional compressional wave at the boundary of a tunnel or a borehole.