How the Temple will Survive Earthquakes

the Salt Lake Temple of the Church of Jesus Christ of Latter-day Saints was built by early church members as a dedicated place of worship and learning it took 40 years to complete and was dedicated in 1893. since then hundreds of other temples have been built around the world each Temple is literally considered a house of the Lord where the presence of God can dwell it is a sacred place where faithful members of the church receive and remember the great and precious Promises of God temples are designed to lift and Inspire and are maintained to safeguard

their holy purposes over the years the Salt Lake Temple has undergone several renovations but in 2019 Church leadership announced the largest renovation yet a complete seismic upgrade with reinforcements that reach from below the foundations to the tips of the spiers this massive and complex project was designed to use the latest in seismic engineering technology knowing it would take years to complete these Interlocking Systems are the result of much research into the nature of earthquakes and how they damage Stone buildings like the temple when an earthquake occurs shock waves cause the Earth to vibrate back and

forth shaking the buildings overhead shaking causes breakage and weak points in the structure can pull apart if the shaking is high enough wide scale failure and collapse can occur the best known methods to prevent this are base isolation and structural reinforcement base isolation is the process of installing mechanical systems below the building that isolate the Earth's movement from the structure overhead in effect they allow the Earth to move beneath while the building overhead remains more stable while such systems can be very effective they are not perfect and some movement can still be transferred to the

building risk of damage can be further reduced through structural reinforcement the goal of structural reinforcement is to ensure that if a building does move during an earthquake it moves as one Consolidated object the seismic upgrade of the Salt Lake Temple includes both base isolation and structural reinforcement systems since this type of renovation involves creating New Foundations below the originals each step must be completed in a specific sequence to keep the building safe and secure during the process before any new additions to the foundation are made the original footings must be Consolidated and reinforced this is

done by Excavating the footings until they are exposed then drilling a network of holes at different angles and locations around the entire Foundation a high-strength grout mixture is then injected to fill any existing spaces between the stones to further strengthen the footings steel rods are then placed across the footings and tensioned steel rod and cable reinforcements are especially valuable in the seismic upgrade of a stone structure like the Salt Lake Temple alone stone blocks and grout can carry massive amounts of weight but can crack and break when subject to lateral movement adding various types of

Steel reinforcement however can provide the additional strength to keep a stone structure from collapsing even if minor damage does occur after the footings are Consolidated reinforced cylindrical beams are installed side by side under the full length of the original Foundation reinforced cylindrical beams are large steel pipes filled with concrete that contain reinforcing steel and cables they are placed directly beneath the original footings and will eventually become part of the new upper Foundation but before they can be installed the ground must be excavated deep enough that the cylindrical beams can be inserted horizontally using what is

called a Jack and bore process but the shear size and weight of a building like the Salt Lake Temple can complicate the process it is estimated that the Salt Lake Temple weighs about 187 million pounds or 85 million kilos this is about the same weight as a full-size aircraft carrier except the aircraft carrier spreads that weight over an area 12 times larger than the temple such tremendous pressure on the earth below had to be taken into account prior to excavation if too much Earth is removed this pressure can squeeze the Earth out from beneath the

temple with disastrous results a 40-foot secant wall made of interlocking steel and concrete columns was designed to keep everything secure and in place the wall acts like a giant collar keeping the Earth beneath the stone structure stable while the reinforced cylindrical beams are installed as each cylinder is placed additional concrete is used to fill in any gaps above and below until the original Foundation rests completely on this new enlarged platform the next step is to install the lower Foundation the lower Foundation rests at an even deeper level and completely frames the existing foundation on both

sides it is six feet thick and reinforced with large steel bars the lower Foundation supports the base isolators this project requires 98 of them to safely support the weight of the temple each base isolator is seven feet across and has the capacity to support over 8 million pounds during an earthquake it can allow up to five feet of horizontal movement in any direction without failing during this phase of the renovation work on the structural Integrity also moves forward on each side of the original roof trusses new trusses capable of bearing greater loads are installed besides

strengthening the roof they also provide additional bracing between the North and South walls steel cables connect the roof trusses to the foundation below and reinforce the walls and Towers a process called vertical coring creates the shafts they pass through vertical coring is the process of drilling super precise holes all the way from the top of the walls down to the New Foundation reinforced concrete bonding beams poured along the top of the walls then connects the roof trusses the walls and the steel cables to the New Foundation these bonding beams further reinforce the connection between the

sidewalls and the end towers as well in the towers additional reinforcement systems are designed to run to the very top of each Spire all of these structural reinforcements connect together and anchor in the transfer beams of the upper Foundation transfer beams are massive 15 foot tall concrete supports that sit directly on base isolators as they are poured they envelop the ends of these cylindrical beams creating a bridge-like Consolidated platform they connect the vertical wall cables to the upper foundation and in turn to the bonding beams and the roof trusses once the upper Foundation is complete

it will transfer the way to the temple completely onto the base isolators and the Earth beneath the cylindrical beam platform and the original foundations is removed all these connected systems have been designed to reinforce and consolidate the temple structure making it much more resistant to seismic damage these improvements help ensure that the iconic Salt Lake Temple will continue to stand as a worldwide symbol of faith in Jesus Christ and a place of worship for hundreds of years to come foreign