Treatment design of geological defects in dam foundation of Jinping I hydropower station

Jinping I hydropower station is one of the most challenging projects in China due to its highest arch dam and complex geological conditions for construction.After geological investigation into the dam foundation,a few large-scale weak discontinuities are observed.The rock masses in the left dam foundation are intensively unloaded,approximately to the depth of 150–300 m.These serious geological defects lead to a geological asymmetry on the left and right banks,and thus some major diffculties of dam construction are encountered.In this paper,the influences of geological defects on the project are analyzed,followed by the concepts and methods of treatment design.Based on the analysis,the treatment methods of the weak rock masses and discontinuities are carefully determined,including the concrete cushion,concrete replacement grids,and consolidation grouting.They work together to enhance the strength and integrity of the dam foundation.Evaluations and calibrations through geo-mechanical model tests in combination with feld monitoring results in early impoundment period show that the arch dam and its foundation are roughly stable,suggesting that the treatment designs are reasonable and effective.The proposed treatment methods and concepts in the context can be helpful for similar complex rock projects.

Direct measurement of the break-out ^(19)F(p,γ)^(20)Ne reaction in the China Jinping underground laboratory(CJPL)

Calcium production and the stellar evolution of first-generation stars remain fascinating mysteries in astrophysics.As one possible nucleosynthesis scenario,break-out from the hot carbon–nitrogen–oxygen(HCNO)cycle was thought to be the source of the calcium observed in these oldest stars.However,according to the stellar modeling,a nearly tenfold increase in the thermonuclear rate ratio of the break-out ^(19)F(p,γ)^(20) Ne reaction with respect to the competing ^(19)F(p,α)^(16) O back-processing reaction is required to reproduce the observed calcium abundance.We performed a direct measurement of this break-out reaction at the China Jinping underground laboratory.The measurement was performed down to the low-energy limit of E_(c.m.)=186 keV in the center-of-mass frame.The key resonance was observed at 225.2 keV for the first time.At a temperature of approximately 0.1 GK,this new resonance enhanced the thermonuclear ^(19)F(p,γ)^(20) Ne rate by up to a factor of≈7.4,compared with the previously recommended NACRE rate.This is of particular interest to the study of the evolution of the first stars and implies a stronger breakdown in their“warm”CNO cycle through the ^(19)F(p,γ)^(20) Ne reaction than previously envisioned.This break-out resulted in the production of the calcium observed in the oldest stars,enhancing our understanding of the evolution of the first stars.

English Translation of Chinese Natural Ecological Discourse:A Corpus-based Case Study on Xi Jinping:The Governance of China

Amid the increasingly severe global natural eco-environment,it is necessary to build a natural ecological civilization by constructing an ecological civilization discourse.Against this background,this study compiles a corpus of natural ecological discourse in the English translation of Xi Jinping:The Governance of China(short for Xi).By using Wordsmith and AntConc,this study explores the linguistic features of the ecological discourse in English translation of Xi in the following dimensions,including high-frequency words,keywords,word collocations,concordance lines.This study aims to analyze the concepts and attitudes towards natural ecology,so as to provide certain valuable insights for the construction of China’s discourse on natural ecological civilization.The study found that the natural ecology discourse involving in the English translation of Xi turned out to be ecologically beneficial.

Preliminary research and scheme design of deep underground in situ geo-information detection experiment for Geology in Time

The deep earth,deep sea,and deep space are the main parts of the national“three deep”strategy,which is in the forefront of the strategic deployment clearly defined in China’s 14th Five-Year Plan(2021-2025)and the Long-Range Objectives Through the Year 2035.It is important to reveal the evolutionary process and mechanism of deep tectonics to understand the earth’s past,present and future.The academic con-notation of Geology in Time has been given for the first time,which refers to the multi-field evolution response process of geological bodies at different time and spatial scales caused by geological processes inside and outside the Earth.Based on the deep in situ detection space and the unique geological envi-ronment of China Jinping Underground Laboratory,the scientific issue of the correlation mechanism and law between deep internal time-varying and shallow geological response is given attention.Innovative research and frontier exploration on deep underground in situ geo-information detection experiments for Geology in Time are designed to be carried out,which will have the potential to explore the driving force of Geology in Time,reveal essential laws of deep earth science,and explore innovative technologies in deep underground engineering.

NνDEx-100 conceptual design report

Observing nuclear neutrinoless double beta (0vββ) decay would be a revolutionary result in particle physics.Observing such a decay would prove that the neutrinos are their own antiparticles,help to study the absolute mass of neutrinos,explore the origin of their mass,and may explain the matter-antimatter asymmetry in our universe by lepton number violation.We propose developing a time projection chamber (TPC) using high-pressure ^(82)SeF_(6) gas and Topmetal silicon sensors for readout in the China Jinping Underground Laboratory (CJPL) to search for neutrinoless double beta decay of82Se,called the NvDEx experiment.Besides being located at CJPL with the world’s thickest rock shielding,NvDEx combines the advantages of the high Qββ(2.996 MeV) of82Se and the TPC’s ability to distinguish signal and background events using their different topological characteristics.This makes NvDEx unique,with great potential for low-background and high-sensitivity 0 vββsearches.NvDEx-100,a NvDEx experiment phase with 100 kg of SeF_(6)gas,is being built,with plans to complete installation at CJPL by 2025.This report introduces 0 vββ physics,the NvDEx concept and its advantages,and the schematic design of NvDEx-100,its subsystems,and background and sensitivity estimation.

Rock mechanical problems and optimization for the long and deep diversion tunnels at Jinping Ⅱ hydropower station

According to site-specific environments such as high water pressures, high in-situ stresses and strong rockbursts, the design scheme of the long and deep diversion tunnels at Jinping II hydropower station was optimized to ensure construction safety. New drainage tunnels were considered. Furthermore, lining structures and grouting pressures were modified during the excavation of tunnels. The construction scheme was updated dynamically based on the complex geological conditions. For instances, the diversion tunnels were first excavated by drilling and blasting method at the first stage of construction, and then by the combination method of tunnel boring machine （TBM） and drilling and blasting, and finally by drilling and blasting method. Through optimized scheme and updated construction scheme, the excavation of diversion tunnel #1 was successfully completed in June, 2011. This paper summarizes the key issues in rock mechanics associated with the construction of the long and deep diversion tunnels at Jinping II hydropower station. The experiences of design and construction obtained from this project could provide reference to similar projects.

Measures for controlling large deformations of underground caverns under high in-situ stress condition--A case study of JinpingⅠhydropower station

The Jinping I hydropower station is a huge water conservancy project consisting of the highest concrete arch dam to date in the world and a highly complex and large underground powerhouse cavern. It is located on the right bank with extremely high in-situ stress and a few discontinuities observed in surrounding rock masses. The problems of rock mass deformation and failure result in considerable challenges related to project design and construction and have raised a wide range of concerns in the fields of rock mechanics and engineering. During the excavation of underground caverns, high in-situ stress and relatively low rock mass strength in combination with large excavation dimensions lead to large deformation of the surrounding rock mass and support. Existing experiences in excavation and support cannot deal with the large deformation of rock mass effectively, and further studies are needed. In this paper, the geological conditions, layout of caverns, and design of excavation and support are first introduced, and then detailed analyses of deformation and failure characteristics of rocks are presented. Based on this, the mechanisms of deformation and failure are discussed, and the support adjustments for controlling rock large deformation and subsequent excavation procedures are proposed. Finally, the effectiveness of support and excavation adjustments to maintain the stability of the rock mass is verified. The measures for controlling the large deformation of surrounding rocks enrich the practical experiences related to the design and construction of large underground openings, and the construction of caverns in the Jinping I hydropower station provides a good case study of large-scale excavation in highly stressed ground with complex geological structures, as well as a reference case for research on rock mechanics.

Investigation of meso-failure behaviors of Jinping marble using SEM with bending loading system

In th is study, th e m eso-failure m ech an ism an d fracture surface o f Jinping m arble w ere investigated bym ean s o f scanning electro n m icroscope （SEM） w ith ben d in g loading system and laser-scanner equipment. The Y antang an d B aishan m arbles specim ens from Jinping II hyd ro p o w er sta tio n w ere used. Testresu lts show th a t th e fracture to u g h n ess and m echanical behaviors o f Y antang m arble w ere basicallyh ig h er th a n th o se o f Baishan m arble. This is m ainly d u e to th e fact th a t Baishan m arble co n tain s a largep ercen tag e o f d o lom ite an d m in o r mica. Crack pro p ag atio n p a th and fracture m orphology in d icated th a tth e d irection o f ten sile stress has a significant effect on th e m echanical behaviors an d fracture toughnesso f B aishan m arble. For Yantang an d B aishan m arbles, a large n u m b e r o f m icrocracks a ro u n d th e m aincrack tip w ere observed w h e n th e directio n o f ten sile stress w as parallel to th e bed d in g plane.C onversely, few m icrocracks o ccurred w h e n th e directio n o f ten sile stress w as p erp en d icu lar to th ebed d in g plane. The presen ce o f a large n u m b e r o f m icrocracks a t th e m ain crack tip d ecreased th e globalfracture to u g h n ess o f m arble. The results o f th re e -p o in t ben d in g te sts show ed th a t th e average bearingcapacity o f intact m arble is 3.4 tim es th e notch ed m arble, b u t th e ductility p ro p e rty o f th e defectivem arble afte r p eak load is b e tte r th a n th a t o f th e intact m arble. H ence, large d efo rm atio n m ay beg en erated before failure o f in tact m arbles a t Jinping II h y d ro p o w er station. The fractal d im en sio n o ffracture surface w as also calculated by th e cube covering m eth o d . O bservational resu lt show ed th a t th elargest fractal dim en sio n o f Y antang m arble is cap tu red w h e n th e directio n o f ten sile stress is parallel toth e bedding plane. H ow ever, th e fractal d im en sio n o f fracture surface o f Yantang an d Baishan m arblesw ith ten sile stress vertical to th e bed d in g plane is relatively sm all. The fractal d im en sio n can also be usedto characterize th e ro ughness o f fracture surface o f rock m aterials.

Tempo-spatial characteristics and influential factors of rockburst:a case study of transportation and drainage tunnels in Jinping Ⅱ hydropower station

Jinping Ⅱ hydropower station is located in a high in-situ stress region in Southwest China. During the excavations of the transportation and drainage tunnels, more than 460 rockburst events were recorded in the transportation tunnel and 110 in the drainage tunnel, which has a serious and negative influence on the tunnels’ construction and the safety of staff and equipment. In the paper, the characters of rockburst patterns are analyzed for the transportation and drainage tunnels. The results are illustrated as follow: (1) Most of intensive rockbursts occur in the layer T2b, and continuous occurrences of rockbursts are more frequently observed than those in other layers. (2) The critical overburden depth of rockburst in the transportation tunnel is 600 m, and the length of the continuous occurrence section of rockburst is smaller than 25 m. The damaged depth of the rockburst has the tendency to increase with the increasing overburden depth, and the maximum damaged depth is over 3.5 m. (3) From east to west (west to east) in Jinping Ⅱ hydropower station, the rockburst usually takes place in the right (left) side of tunnel working face, and then the left (right) or roof of the tunnel. The total length of the continuous occurrence section of rockburst is 57.4%–62.2% of the overall rockburst length, followed by the rockbursts of flake-splitting type and other types. (4) Compared with the transportation tunnel, the intensity of rockburst in the drainage tunnel is higher while the length of the continuous occurrence section of rockburst is smaller. The rockburst section with length less than 10 m and depth of 1 m mainly occurs in the layer at a depth of 1 800–2 000 m. The influences of opening geometry and excavation method on the characteristics of the adjacent zone are great, but the influence of the stress among the tunnel group induced by excavation is relatively low.

Key technologies for construction of Jinping traffic tunnel with an extremely deep overburden and a high water pressure

Jinping traffic tunnel is one of the deepest traffic tunnels in the world with a maximum overburden of 2 375 m and the overburden over 73% of its total length is larger than 1 500 m. The tunnel is 17.5 km long and designed to provide a shortcut road between two hydropower stations： Jinping I and Jinping II of the Jinping Hydropower Project, located on Yalong River, Liangshan State, Sichuan Province, China. The tunnel is so deep that building any shafts is impossible. The construction starts from both ends （east and west ends）, and the construction length from the west end is 10 km with a blind heading. This paper deals with an overview of this project and analysis of the engineering features, as well as key technologies developed and applied during the construction, including geological prediction, rock burst prevention under a super high in-situ stress, sealing of groundwater with a high pressure and big flow rate, ventilation for a blind heading of 10 km, wet spraying of shotcrete at zones of rock burst and rich water, etc. The application of the new technologies to the construction achieved a high quality tunnel within the contract period.

BUILDING A MODERATELY PROSPEROUS SOCIETY IN ALL RESPECTS——Poverty Reduction: Xi Jinping’s Statements and Chinese Path

After the founding of the People’s Republic of China, the Chinese people have been struggling against poverty amid national development under the leadership of the Communist Party of China(CPC). Since reform and opening up, in particular, China has planned for and organized development-oriented poverty reduction practices on a broad scale with remarkable achievements and blazed a new path of development-oriented poverty reduction with Chinese characteristics. This path is both an essential component of Chinese socialism and a result of the CPC’s ideological improvement on poverty reduction. Since the 18 th CPC National Congress in 2012, the whole Party, country, and society have been called upon to fight the battle against poverty on a full-scale under the guidance of General Secretary Xi Jinping’s important statements on poverty reduction, unveiling a new stage for China’s development-oriented poverty reduction in the new era. China’s unprecedented poverty reduction achievements have enriched the path of poverty reduction with Chinese characteristics. Xi Jinping’s insightful and coherent statements on poverty reduction represent the latest results of Marxist anti-poverty theories and comprise an essential part of Xi Jinping Thought on Socialism with Chinese Characteristics for the New Era. His guidelines are the basis for the brilliant achievements of China’s poverty reduction endeavors, and will contribute Chinese experience and wisdom to global poverty governance.

The Construction and Characteristics of the Theoretical System of Xi Jinping’s View of History

Xi’s historical view is a scientific theoretical system with a tight logical structure.The construction of this theoretical system follows the principles and methods of the construction of Marxist theoretical system.The theoretical features of Xi’s view of history are unity of theory and practice,unity of politics and science,unity of universality and nationality,unity of collective wisdom and individual wisdom,unity of dialectical thinking and historical thinking,and unity of history,reality,and future.

Xi Jinping:The Governance of China

THE Foreign Languages Press recently published a book that sheds light on the approach of China＇s new leadership to govern-ance. Xi ]inping： The Governance of China was compiled jointly by the State Council Information Office, the Party Literature Research Office of CPC Central Committee and China International Publishing Group （CIPG）

Xi Jinping: The Governance of China Ⅲ Comprehensive Vision and Creative Ideas

THE third volume of Xi Jinping:The Governance of China was published on June 30,2020.It comes after the first volume of the magnificent work that covers the period from November 15,2012 to June 13,2014,and the second volume that covers the period from August 18,2014 to September 29,2017.The third volume of Xi Jinping:The Governance of China contains a compilation of 92 of the president’s spoken and written works,including reports,addresses,talks,speeches,written instructions,and letters from October 18,2017 to January 13,2020.This book was jointly compiled by the State Council Information Office,the Institute of Party History and Literature of the CPC Central Committee,and China International Publishing Group(CIPG).

Xi Jinping's Congratulatory Letter to the 2015 Beijing Forum on Human Rights

On the occasion of the 70th anniversary of the victory of the Chinese People’s War of Resistance against Japanese Aggression as well as the World Anti-Fascist War,the Beijing Forum on Human Rights this year is themed with"Peace and Development:Victory of World Anti-Fascist War and Human Rights Advancement,"which helps all parties deeply reflect on the

Internal Logic and Significance of Times in Xi Jinping s Important Exposition of Poverty Alleviation

Eliminating poverty is the essential requirement of socialism. Since the 18th National Congress of the Communist Party of China, targeted poverty alleviation has become a major strategy for poverty alleviation and development in China. Xi Jinping s important exposition of poverty alleviation is the theoretical basis and practical guide to direct the effective implementation of China s targeted poverty alleviation strategy. It has gradually developed into an innovative theoretical system for poverty alleviation and development in the new era, with meticulous internal logic and a reputation for the significance of the times at home and abroad. Xi Jinping s thought of targeted poverty alleviation is the development and innovation of the theory and practice of poverty alleviation and development with Chinese characteristics. It is an important guarantee for China to win the battle to get rid of poverty and build a well-off society in an all-round way, and has contributed China s wisdom and China s plan to reducing poverty in the world.

A Study of Xi Jinping Thought on Governing the Country Based on the Unity of “Party Spirit-People’s Nature”

The unity of “party spirit-people’s nature” is the basic proposition of Xi Jinping’s governance.Deng Xiaoping summarized the experience and lessons in the early days of reform and opening up,and put forward the basic line of the “leadership and unity” of the party in the early stage of socialism around “one center,two basic points”;Xi Jinping’s so-called “unification”,which is based on the the basic line of Deng Xiaoping’s initial stage of building a socialist country that is “rich,strong,democratic,civilized,harmonious and beautiful”,has further established the importance of “people as the center” and “party’s leadership”.Therefore,the “people-centered” and “the party’s overall leadership” are unified and become the basic idea of General Secretary Xi Jinping’s governance of the country.Xi Jinping has put forward the unity of “party spirit-people’s nature”,the “consistency” between governing the country and politics,and the “integration” between the people’s interests and the party’s leadership,thus forming “persistence”,“comprehensive”,“confidence”,“maintenance” and other assertions.

The Scientific System of Xi Jinping Thought on Socialist Culture with Chinese Characteristics for a New Era

Since the 18 th CPC National Congress,the Party Central Committee,with Comrade Xi Jinping as the core,has formed Xi Jinping Thought on Socialism with Chinese Characteristics( Xi's TSCC) for a New Era in the process of upholding and developing the great practice of Socialism with Chinese Characteristics( SCC). As an important part of Xi's TSCC for a new era, cultural thought takes the persistence of cultural confidence as its basic foundation,t he promotion of outstanding traditional culture as its important measure,the enhancement of cultural soft power as its strategic goal,t he cultivation &practice of core socialist values as its guide, and the improvement of clean government culture as its fundamental significance,t hus constituting a scientific system with complete structure, rich content and rigorous exposition. This important thought provides a powerful theoretical and practical guide to the work of building a socialist culture with Chinese characteristics in the new era.

Xi Jinping’s Analysis of “A Common Future for Humanity”:Its Relation to Marx’s Das Kapital

President Xi Jinping’s analysis of “a common future for humanity” is one of the most important and original features of China’s foreign policy and of “Xi Jinping’s Thought on Socialism with Chinese Characteristics for a New Era”.This concept is comprehensible not only in classical Chinese but in Western philosophical thought.Therefore,it is a creative development of Marxism whose accurate relation to economic reality,provides an exceptionally firm basis for China’s foreign policy and that of other countries.

On the Four Dimensions of Xi Jinping’s Ecological View

Since the 18th CPC National Congress,the Party Central Committee with General Secretary Xi Jinping as the core has been committed to the construction of ecological civilization,scientific and in-depth understanding of the law of human and economic and social development,creatively proposed a series of new strategies,and has formed a comprehensive and systematic Xi Jinping’s ecological view.The basic connotation is:adhering to the ecological economic view of green development,focusing on the domestic and international ecological political view,constructing an ecological cultural view in harmony between man and nature,and an ecological social view unifying environmental protection and people’s happinesses.Xi Jinping’s ecological view is the inheritance and development of Marxist ecological theory,the enrichment and perfection of theoretical system of socialism with Chinese characteristics (SCC),the new understanding of the laws governing the development of human civilization,the important content for the Chinese dream,and an action to build a beautiful China,thus contributing Chinese wisdom to global ecological governance.