无线倾角传感器监测英国圣马利亚大教堂

英国英格兰St Mary教堂最早可以追溯到11世纪，教堂的原始建筑始建于1180年左右，是在一个木制的盎格鲁 – 撒克逊教堂遗址上修缮而成。1990年，St Mary教堂其特殊的建筑和历史价值被列入建筑物和保护区法案。 在13和14世纪左右，St Mary教堂断断续续又进行了修整。

直到最近，我们收到了来自St Mary教堂牧师朱尔斯对我们公司倾角传感器的需求，大概内容是：自1766年，我们教堂的塔楼进行重建以后，直到2018年3月，塔楼倾斜了1.4°；这个月，塔楼倾斜了2.1°。由于塔楼倾斜所产生的压力，使他对周围其它建筑造成了墙体结构开裂和建筑物移动等问题。据估计，该塔楼重约300吨。塔楼产生的压力太大，使之一直从塔楼到圣坛的建筑都发生了倾斜。本来在该塔楼的墙上，我们挂着一只大钟。墙体悬挂6个铃铛，可以给我们准时报点。现在为了方便监测，我们已暂停铃声，以便我们可以得到准确的监测数据。我们初步认为教堂的底部基岩是石膏成分，而石膏材质在干燥天气非常容易收缩，这就是导致现在的问题之一。我们已向政府申请拨款查明沉降的原因，该调查和补救工程的初步费用估计数额为600,000美元。

在教堂倾斜的情况更加严重之前，我们希望对建筑进行实时监测，有助于提示我们接下来要采取的措施，保证补救措施的有效性。我们希望在距离主楼最远的建筑上安装倾角传感器，同时在塔楼的底部，中间和顶部都装上倾角传感器进行监测。

The tower (that is leaning) is one that was rebuilt in 1766, after the original tower had to be demolished (they may have had the same problem!). In March 2018 the tower was leaning by 1.4 degrees; this month, it is leaning by 2.1 degrees. The tower is putting a lot of stress on the rest of the building, causing major structural cracking and movement, all the way to the opposite end (the chancel) of the building. The tower houses a clock, driven by large suspended weights which are rewound every week, and also 6 bells, the oldest dating to about 1600; we have suspended the bell ringing until we have the monitoring in place, so that we can measure any effects the bell ringing may have on the tower. It is estimated that the tower weighs around 300 tonnes.

We have applied for a grant to help us investigate the cause of the subsidence, in order to provide a solution – the underlying bedrock is gypsum and the soil is very susceptible to shrinkage in dry weather, which is what we think the problem may be. Initial cost estimates for the investigation and remedial works is in the order of $600,000. The monitoring will help by warning us of any further movement and will also measure the effectiveness of any remedial action.

We will install the inclinometers at the base, mid way and top of the tower, on the face furthest from the main building.

教堂由于年代久远，塔楼本身开始倾斜，这个问题对教堂的整体结构产生了毁灭性的影响。St Mary教堂牧师朱尔斯选择直川无线倾角传感器ZCT800ML去测量塔的倾斜度。上海直川科技研发的LORA无线倾角传感器，精度高达0.001°，网关和倾角最远距离可达2~3公里。­St Mary教堂牧师随时可以在电脑前查看教堂的倾斜情况。希望直川的无线LORA倾角传感器像遥远的守护神一样，守护教堂的安全。