رفتن به مطلب

پست های پیشنهاد شده

در این تایپیک قصد داریم مقالات به روز و زبان اصلی مکانیک سنگ و تونل سازی رو براتون قرار بدیم.

امیدوارم مفید باشه.. :icon_gol:

به اشتراک گذاری این ارسال


لینک به ارسال
به اشتراک گذاری در سایت های دیگر

ELASTO-PLASTIC SOLUTION OF TUNNEL PROBLEMS USING

THE GENERALIZED FORM OF THE HOEK-BROWN FAILURE CRITERION

 

Abstract: The Hoek-Brown failure criterion is a semi-empirical method widely used in the estimation of shear

strength of rock. Among other parameters involved in this criterion, the coefficient a dictates whether the criterion

applies to intact rock or rock masses (a = 0.5 for intact rock anda > 0.5 for rock masses). Most of the existing

elasto-plastic solutions for tunnel problems in Hoek-Brown media consider an intact rock (i.e., a = 0.5). This

is not only due to historical reasons (the failure criterion was originally developed for intact rock), but also due

to the mathematical difficulties of deriving neat, closed-form expressions for the general case in which a ≥ 0.5.

This paper presents a rigorous, elasto-plastic solution for the axi-symmetrical problem of excavating a circular

tunnel in generalized Hoek-Brown material (a ≥ 0.5). The solution is obtained by re-writing the generalized

Hoek-Brown failure criterion in terms of transformed stress quantities. Application of the transformation rule

described in this paper to elasto-plastic problems of excavations in generalized Hoek-Brown materials is shown

to bring significant advantages in the interpretation and extrapolation of results obtained with analytical and

numerical methods. C. Carranza-Torres1

2B 28 Carranza Torres.pdf

به اشتراک گذاری این ارسال


لینک به ارسال
به اشتراک گذاری در سایت های دیگر

Penetration rate of TBMs

SYNOPSIS: A number of empirical relationships have been in vogue to predict the penetration rate of

TBMs. These relations consider compressive strength, tensile strength, hardness test data, RQD, RSR, RMR,

Q-values etc., either independently or in combination with some of these parameters. Barton proposed an

elaborate expression consisting of 21 parameters. Experimental studies in Italian Alps on the performance of

TBM in medium to hard metamorphic rocks revealed considerable deviation from Barton-approach.

A simple expression dimensionally correct to predict penetration rate is presented considering the basic TBM

data, properties of rock mass and also intact rock, in situ stress and drilling rate index of rock. It has been

verified with the data from 16 rock types of Maen and Pieve tunnels in Italian Alps giving very encouraging

results. A brief mention is also made how to predict advance rate of TBMs.

 

 

160.PDF

به اشتراک گذاری این ارسال


لینک به ارسال
به اشتراک گذاری در سایت های دیگر

A MAMDANI FUZZY INFERENCE SYSTEM FOR THE GEOLOGICAL STRENGTH

INDEX (GSI) AND ITS USE IN SLOPE STABILITY ASSESSMENTS

Abstract: The strength and deformation modulus of closely jointed rock masses can be estimated by using

the Hoek and Brown empirical criterion in conjunction with the Geological Strength Index (GSI)

classification system. To minimize the uncertainties of the rock masses, experienced engineers commonly

use the engineering judgment. Intervals of the GSI, rather than point-valued observations, are also likely to

be obtained when using the original GSI chart. This study is an attempt to provide an approach on the fuzzy

set theory for determining GSI ratings to be used by the empirical failure criterion. For the purpose, the

original GSI system and its quantitative modified form were defined by fuzzy sets, and Mamdani fuzzy

algorithm was constructed employing 23 “if-then” rules. In addition, the validity of the approach and

methodology of parameter estimation were checked by back analysis of the well-documented slope

instabilities occurred in the heavily jointed rock masses

A Mamdani fuzzy.pdf

به اشتراک گذاری این ارسال


لینک به ارسال
به اشتراک گذاری در سایت های دیگر

Shallow Cover Tunnel Under Heritage Listed Brick Buildings:

 

Brisbane Boggo Road Busway Tunnel

 

Introduction

The use of underground space for new transport infrastructure in urban environments has become very common due to space constraints. In built-up areas these tunnels will often pass under sensitive buildings. This article presents a case study on a shallow cover driven busway tunnel under heritage-listed buildings on shallow footings. Phase2 (in design), Unwedge and Dips computer software packages were used extensively. The latter two packages were used extensively during tunnel excavation.

case study.pdf

به اشتراک گذاری این ارسال


لینک به ارسال
به اشتراک گذاری در سایت های دیگر

Influence of rock mass properties on TBM penetration

 

rate in Karaj-Tehran water conveyance tunnel

 

Predicting penetration rate (PR) of tunnel boring machine (TBM) due to the properties of rock mass

surrounding tunnel has been an important subject in the mechanized method of excavating tunnel.

Influence of uniaxial compressive strength (UCS), Brazilian tensile strength (BTS), peak slope index

(punch penetration), spacing of discontinuities (of weakness planes), orientation of discontinuities with

respect to the tunnel axis (Beta angle) on penetration rate of TBM was investigated while excavating Karaj-

Tehran water conveyance tunnel by a double shield Herencnesht TBM. Statistic analysis was carried

out on the relationship between measured test results of the five different parameters of rock mass

properties and the penetration rate of TBM. The results showed that each of the five different

parameters of rock mass properties individually has affected the penetration rate of TBM. The

relationship between peak slope index (PSI) and penetration rate of TBM has the best correlation

coefficient ® of 0.57 in comparison with the four others relationship between rock mass properties and

the penetration rate of TBM. The relationship between BTS of rock and PR of TBM has a very poor

correlation coefficient ® of 0.11. Multilinear regression analysis was applied to indicate the combined

influence of the five different rock mass properties on the penetration rate of TBM using a database of

measured test results. A new empirical formula was achieved to predict PR of TBM as a function of

different rock mass properties (r = 0.75).

Mansouri and Moomivand.pdf

به اشتراک گذاری این ارسال


لینک به ارسال
به اشتراک گذاری در سایت های دیگر

محتوای مخفی

    برای مشاهده محتوای مخفی می بایست در انجمن ثبت نام کنید.

 

محتوای مخفی

    برای مشاهده محتوای مخفی می بایست در انجمن ثبت نام کنید.

به اشتراک گذاری این ارسال


لینک به ارسال
به اشتراک گذاری در سایت های دیگر

tunneling.jpg

 

 

نام لاتین کتاب : Introduction to Tunnel Constraction

 

نام فارسی کتاب : مقدمه ای بر ساخت تونل

 

ناشر :Alfred Stärk , David Chapman, Nicole Metje

 

سال انتشار : ۲۰۱۰

 

لینک دانلود :

محتوای مخفی

    برای مشاهده محتوای مخفی می بایست در انجمن ثبت نام کنید.

به اشتراک گذاری این ارسال


لینک به ارسال
به اشتراک گذاری در سایت های دیگر

با تشکر فراوان از لطف شما

لینک ترجمه مقاله غیر فعاله لطفا رسیدگی کنید

به اشتراک گذاری این ارسال


لینک به ارسال
به اشتراک گذاری در سایت های دیگر

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

مهمان
ارسال پاسخ به این موضوع ...

×   شما در حال چسباندن محتوایی با قالب بندی هستید.   حذف قالب بندی

  تنها استفاده از ۷۵ اموجی مجاز می باشد.

×   لینک شما به صورت اتوماتیک جای گذاری شد.   نمایش به عنوان یک لینک به جای

×   محتوای قبلی شما بازگردانی شد.   پاک کردن محتوای ویرایشگر

×   شما مستقیما نمی توانید تصویر خود را قرار دهید. یا آن را اینجا بارگذاری کنید یا از یک URL قرار دهید.


×
×
  • جدید...