板式橡胶伸缩装置中的伸缩体是由橡胶、钢板或角钢硫化为一体的构造，它是利用橡胶材料剪切模量低的原理设计制造而成。即剪切型橡胶伸缩体设有上下凹槽，橡胶体内埋设承重钢板和锚固钢板，并设有预留螺栓孔，通过螺栓与梁端连成整体。
The expansion body of plate rubber expansion device is made of vulcanized rubber, steel plate or angle steel. It is designed and manufactured according to the principle of low shear modulus of rubber material. That is to say, the shear rubber expansion body is provided with upper and lower grooves, the load-bearing steel plate and anchoring steel plate are embedded in the rubber body, and the reserved bolt holes are arranged, which are connected to the end of the beam through the bolts as a whole.
它是依靠上下凹槽之间的橡胶体剪切变形来满足梁体结构的相对位移。橡胶伸缩体内预埋钢板，跨越梁端间隙，承受车辆荷载。另外在橡胶伸缩体内两侧预埋两块锚固钢板，通过螺栓与梁端连接的受力原理形成的结构构造，一般适用于伸缩量小于60mm的公路桥梁工程。
It relies on the shear deformation of the rubber body between the upper and lower grooves to satisfy the relative displacement of the beam structure. The steel plate embedded in the rubber expansion body crosses the gap at the end of the beam and bears the vehicle load. In addition, two anchoring steel plates are embedded on both sides of the rubber expansion body, and the structure formed by the stress principle of bolt and beam end connection is generally suitable for highway bridge projects with the expansion less than 60 mm.
常用桥梁伸缩缝大家应该都了解，就是我们平常说的C、F、E、Z、D型伸缩缝，间距为40、60、80，但是好坏如何鉴别呢？
1.型钢，桥梁伸缩缝是否采用国标Q235；
2.胶条，有时候大家会认为这个东西应该不能算到质量好坏的范畴之内，但是如果胶条质量不行，很容易让杂物跟积水进入桥梁伸缩缝缝隙当中，很容易影响伸缩，严重时候会产生锈蚀、型钢凸起，使用寿命大大降低。
3.锚固钢筋的粗细跟间距，这个粗细就不解释了，肯定同种质量的东西越粗越结实，但是间距就不一样了，这个密度越高焊接的时候固定点就越多，所以质量也就更好，使用寿命也就更长。
4.钢板（预埋钢板）这个地方看实际情况，一般买家都自己配备。