美国煤炭的地下开采分为长壁式和房柱式两种技术。地质条件较好、井田范围大的矿井，一般以长壁开采为主，否则以房柱开采为主。1994年至2017年，美国地下矿数量减少了79%（2017年为237座）。但是单个矿井产量增加了230%，煤炭生产更加集中、高效。美国长壁开采以中厚煤层为主，采高一般为1.6～2.5m（最大开采高度4.2m，最小开采高度1.2m）。长壁工作面均采用多巷布置、矩形断面巷道、锚杆支护。近些年来，工作面尺寸、设备功率、设备尺寸逐渐增大，生产系统更加可靠。长壁工作面的自动化开采源于1984年的电动控制液压支架的研发与使用，此后开发了支架、采煤机、刮板输送机的单机自动化以及追机移架技术。2000年以后开发了半自动化工作面技术和采煤机远程控制技术。目前应用的主要是半自动化工作面技术，只有2个工作面应用了采煤机远程控制技术。这些技术解决了条件简单工作面的自动化开采问题，但遇到复杂地质条件时，仍需要人工干预。研发自动化开采的关键传感器和设备以适应地质条件变化、完善端部进刀系统，聚焦作业安全和粉尘与噪音防控，以及矿用大数据、高速通信与可视化技术是目前美国的重要研发方向。在近十年来，房柱开采的工艺变化不大，但是开采装备的多样化和开采系统的自动化、信息化、智能化的相关技术开发取得了重要进展。

Underground coal mining in the USA employs two methods: longwall mining and room & pillar mining. Mines with suitable geological condition and sufficient resevres generally use longwall mining, otherwise, room & pillar mining is used. Between 1994 and 2017, the number of underground coal mines in the USA fell by79%, to 237 in 2017. But output from individual mines has risen by 230%, and coal production is more concentrated and efficient. Longwall mining in the USA is mainly practiced in medium-thick seams, and the mining height is generally 1.6~2.5m (maximum height is 4.2m and minimum height is 1.2m). Multi-entry development, rectangular cross-section roadway and roof bolting are all adopted for panel development and roadway configuration and support. In recent years, panel dimensions, equipment power and size continue to increase, production system have become more reliable. Automatic of longwall mining began with the development of shield with electro-hydraulic control technique in 1984. Since then, the technology of single machine automation of shield, shearer, AFC and SISA system has been developed. After 2000, the technology of semi-automatic panel and remote control technology of shearer were developed. At present, the main application is semi-automated longwall face, only 2 panel faces have applied the remote control technology of shearer. These technologies have solved the problem of automated mining in panels with good conditions, but it still needs manual intervention in complex geological conditions. Research and development of key sensors and equipment for automatic mining to adapt to the change of geological conditions, the improvement of face-end operation, operation safety, the control of dust and noise, big data analysis, faster communications and visualization technologies are currently the key fields of research and development in the USA. In recent ten years, the process of room & pillar mining technology has not changed much. However, significant progress has been made in the development of related technologies such as automation, informatization and intelligentization of mining system.

1 引言 

2 长壁开采技术 

　　2.1 工作面布置及尺寸 

　　2.2 工作面开采设备 

　　2.3 美国长壁开采特点及发展趋势

3 自动化长壁开采技术 

　　3.1 单机自动化 

　　3.2 自动化长壁采煤系统 

　　3.3 大数据、高速通信与可视化技术 

　　3.4 自动化开采问题与方向 

4 房柱开采技术 

　　4.1 美国房柱式开采技术发展历程 

　　4.2 美国房柱式开采技术现状及进展 

5 结束语