Mount Tianping Cliff Elevator, China
Team addresses challenges of an extreme environment, resulting in a comfortable ride with stunning views.
by Wang Qibing and Huang Yuanfeng
At every turn, team members from Sicher Elevator and its partners were met with challenges in designing and building a panoramic cliffside elevator for visitors to Mount Tianping, southwest of Linzhou in China’s Henan Province. The process took approximately four years, involved scores of employees, intensive feasibility/engineering work and the ability to respond quickly and thoroughly to unique problems that presented themselves along the way. Major work was completed in late 2013, with inspections and construction of safety features carrying on into 2014.
Sicher was the designer and manufacturer of the unit, the GRO20-III. It has a rise of 120 m, three stops, capacity of 1600 kg and travels at 2 mps. The customer was the Linzhou Mount Tianping Tourism Area. The steel shaft was built by Ding Zhengbin. Zhengzhou Bode Elevator Sales Co., Ltd., performed the installation and holds the maintenance contract.
A top tourist destination that combines natural beauty and history, Mount Tianping lies some 8 km west of Linzhou in Henan Province. The Tianping Temple, originally built in the 540s, is surrounded by 11 mountain peaks, six of which soar higher than the rest and stand between 1,580 and 1,700 m above sea level.
The elevator’s location was carefully chosen by Sicher and tourism officials to provide visitors with easy access to scenic sites and a pleasing, nondisruptive appearance. After several months, the team selected a site close to a 130-m-tall waterfall. The ground landing is located near the foot of the waterfall, allowing visitors the greatest convenience for sightseeing, and the top landing (Yuhua Terrace) boasts a teahouse where people may take a break and enjoy the tranquil waterfall and scenery. Although the area includes a trail, there are no roads for trucks and cranes to go deep into the heart of the steep mountains and valleys.
Once in the mountains, visitors must walk on trails and stone steps. One of the trails leading to Tianping Temple is located not far from the middle rise of the hoistway. To create a direct link to the trail, the lift makes an intermediate landing roughly in the middle of the cliff’s rise (78 m above waterfall level). A section of the cliff rock opposite the elevator was cut open to accommodate a section of trail.
Prior to construction, the feasibility study alone took roughly two years. It included information on geography, geology and meteorology, as well as detailed analyses of the mountain rock structure, waterfalls and winds. The mountainous, geological landscape features a combination of Ordovician limestone, sandstone, shale and quartzite, all vulnerable to erosion from rainwater.
To help guarantee equipment longevity and passenger safety, the glass shaft was built with erosion-proof steel and impact-resistant polycarbonate glass manufactured by Lansing Special Glass Manufacturer, Haining.
Transporting the Materials
A narrow road winds up the mountain a few miles to a parking lot, from which visitors start touring on foot. Elevator materials were unpacked in this parking lot piece by piece, then hung on an overhead cable system (which could handle only limited weight) for transport. The cable pulled the loads up in a straight line, saving workers the trouble of climbing up rugged trails and steep steps with materials. Unfortunately, the cable only reached one-fourth of the whole transport journey (roughly 4 mi.) to the jobsite. For this reason, elevator parts and components, including the traction machine and massive steel beams and supports for the glass shaft, had to go further up manually by trail. The trail measures a little more than 1 m wide, and is full of twists and turns — virtually impossible for wheeled vehicles to traverse.
One of the most difficult parts of the job was laying the foundation for the soaring hoistway. Four steel columns had to be placed upright at each corner of the glass shaft. Due to the shaft’s great height, the columns’ vertical alignment was key to the whole process. The slightest deviation would have led to big problems later on. Strong, changing winds in the valley also complicated the job.
Sometimes, it would take several days to stabilize one of the base columns. As the structure rose, support beams had to be anchored into the cliff wall. On average, the hoistway stands around 4 m away from the cliff. However, this distance varies since the cliff surface is irregular, meaning that support beams had to be cut to proper lengths depending on heights and angles.
Because of the mountain’s vulnerability to erosion, the support beams could not be directly fixed into the rock using anchor bolts, as the inside of the rock was not strong enough to hold the bolts securely. The solution was to preset one end of each beam into the cliff using high-grade cement. At this stage, the project presented a vertical jobsite for workers, who were secured by safety ropes as they traversed the surface like rock climbers.
When installation commenced, Sicher field mechanics noticed a deviation from the plumb lines they had set the night before. After studying the issue, they realized it was caused by temperature fluctuations. To guarantee the precision of future guide-rail erection, they established pairs of reference plumb lines for morning, noon and afternoon temperatures. Such attention to detail resulted in the exceptional ride comfort of the finished product. Work related to 18 inspection doors and a passenger-evacuation ladder continued several months into 2014.