国道108线广元段公路桥梁裂缝病害及加固对策

国道108线广元段由于地质地貌条件复杂、重载作用及施工质量未能保证，桥梁裂缝病害较为普遍。文章简要介绍了沿线工程地质条件，按裂缝病害的成因将其分为3种类型：即桥台填土上部不密实引起的裂缝病害、桥台填土整体不密实引起的裂缝病害及地基土不均匀引起的裂缝病害。分别提出3种加固对策：即压浆、预应力对穿锚索锚梁及高压旋喷技术对上述病害进行治理。通过工程实例证明了这3种措施的有效性，为公路桥梁类似裂缝灾害提供了实践经验。这3种治理措施的优点为工艺简单、成本较低。但是桥梁病害的治理往往为隐蔽工程，施工难度较大、检测困难。对于压浆和高压旋喷加固工程，必须进行取芯检测，而预应力对穿锚索锚梁在施工过程中必须严格控制水平孔的倾斜度，保证施工质量。

Crack disaster of bridges on the 108 National Highway andreinforce measures

The crack disasters of bridge are common in Guangyuan section on the 108 National Highway because of complex geological and geomorphological conditions, heavy loading and bad quality of construction. The authors analyze the engineering geological conditions along the road section. According to genetic classification, the crack disasters are divided into three types, namely, crack disasters caused by the loose fill in upward bridge abutment, crack disasters caused by the loose fill in whole bridge abutment, and crack disasters caused by heterogenous foundation soil. Three types of reinforce measures, mudjack, opthread-prestressed strand anchor and anchor beam and high-pressure rotaing spouting, are correspondingly put forward. It has been proved by engineering cases that the measures are successful to reinforce the crack disasters of bridge. Their merits are with simple technic and low cost. However, the control measures of crack disasters are concealed work with great diffculty of construction and check. It is necessary for mudjack and opthread-prestressed to check quality of construction by obtaining borehole core, and for opthread-prestressed strand anchor and anchor beam, lean of level drilling must be controlled strictly.