Foreword
The ballastless track structure in turnout area of high speed railway is composed of turnout part（steel rail and fastener system，etc），rail bearing structural part，concrete track bed slab and base.At present，the rail bearing structural part mainly falls into slab type（turnout slab）and sleeper type（turnout tie）.
The turnout slab is non-prestressed reinforced concrete prefabricated part，it is produced industrialized by the method of pedestal，the overall dimension of every turnout slab varies according to its different location in turnout area；below the turnout slab on subgrade is poured with self-compacting concrete，in between the turnout on bridge and the base plate cement-emulsified asphalt mortar is poured，to form an integral ballastless track bed in the turnout area.Long sleeper embedment type integral ballastless track bed in turnout area is pretty mamture and widely applied structure type currently.
The first part of this book mainly discusses the construction of slab type ballastless track in turnout area，and the construction technology for slab type ballastless track in turnout area is introduced and explained in four chapters as per working procudures.The first part specifically discusses the structure design of slab type ballastless track in turnout area，track intersection and control measurement in turnout area，and construction of slab type ballastless track in turnout area on subgrade and bridge.The second part discusses the construction of sleeper type ballastless track in turnout area，and the construction technology for sleeper type ballastless track in turnout area is introduced and explained in six chapters as per working procudures，which includes the structure design of sleeper type ballastless track in turnout area；turnout material transportation，storage and hoisting；tack intersection and control measurement in turnout area；construction of sleeper type ballastless track in turnout area on subgrade and bridge；and turnout rail welding，etc.In addition，the fine adjustment for turnout slab and turnout tie as well as the concrete in different working procedures also refers to the technology and valuable experience of CRTS Ⅱ slab and CRTS Ⅰ bi-block ballastless track construction.
The chief editor of this book is Li Changning，associate editors are Dai Yu and Yang Hongwei，and other participants in writing this book include Chang Yawen，Cao Dezhi，Liao Wenhua，Bai Shuangming，Xu Hong，Hou Xiaojun，Bai Yangjun，and Zhu Xiaoyi.We appreciate the guidance and strong support from Guo Fu’an，Gu Qiulai，and Liu Zengjie who are from the Engineering Management Center of China Railway.We also got the support from the Third Railway Survey and Design Institute Group Corporation，and China Railway SIYUAN Survey and Design Group Co.，Ltd.，many thanks to them all.
It must be noted that the prefabrication for turnout slab and turnout tie is not discussed in this book；especially the turnout slab，its prefabrication technology and related standard please refer to the related content for CRTS Ⅱ track board.In addition，compensation board，special board and double board sleepers get involved in the transitional section between slab type ballastless track in turnout area and other track structures，different engineering is of different design.This book takes the actual construction case for explanation，and maybe little different from other engineering；the actual construction case is the transitional section for slab type ballastless track in turnout area in Dezhoug Eastern Station on Beijing-Shanghai High Speed Railway.
There may still be some omissions and mistakes in this book，so valuable comments and suggestions from all readers are welcome for us to modify，supplement and improve in later edition.