Analysis | The Best Solution for the Gaza Tunnels is Sealing
Guest author Dr. Amichai Mittelman, a lecturer at the Department of Civil Engineering at Ariel University, provides his insights
IsraelDefense
| 28/02/2024
Photo: IDF Spokesperson's Unit
Since the dawn of humanity, people have always sought to exploit underground space for various purposes, including military uses. In this context, tunnels offer clear advantages in numerous aspects, particularly due to their being hidden structures and heavily fortified.
Tunnels have been used for offensive and defensive purposes in both World Wars and during the Cold War era. Israel, too, employs defensive use of underground infrastructure, and the bunker in the Kiriya military base is an excellent example of this.
In the years following World War II, the Americans conducted numerous experiments to assess the resilience of tunnels. They invested significant resources in these experiments and derived important conclusions from them.
These experiments were classified in the past, but today are declassified and available, and it is interesting and important to delve into the insights gained from them. Today, the magnificent tunnel network of the Viet Cong from the Vietnam War era stands and serves as a tourist site, a testament to the immense difficulty in destroying tunnels.
In short, a tunnel is a highly resilient structure against various threats. It is extremely difficult to cause a tunnel collapse through an explosion, requiring enormous amounts of explosives and ideal implementation. The explosion needs to be carried out in a way that causes the ceiling of the tunnel to collapse inward, thus blocking passage inside.
When detonating the tunnel within the airspace, the blast wave is expected to propagate and cause damage only to the immediate surroundings. Additionally, the likelihood of a blast within the tunnel's airspace causing a complete collapse of the tunnel is low.
Today, the State of Israel is facing an unprecedented military tunnel network in terms of its scope, which is notably more advanced than the Vietnamese network.
The media is talking about hundreds of kilometers and thousands of tunnels. While in the past, the central research effort was invested in developing means of detecting infiltrating tunnels, the advantages that these tunnels provide to the enemy on the battlefield require renewed readiness.
Contrary to explosions, another direction that has been attempted to deal with military tunnels is water flooding. Water resources are abundant, and Gaza's coastal location has prompted Egyptians to utilize this method in the past.
According to various reports, the IDF has also explored this direction during the current conflict. It is unclear what the results of this attempt were, but according to reports, the results were very limited and localized and did not lead to the desired outcome of neutralizing the threat.
It is also important to note that solutions based on the destruction of underground infrastructure, such as explosives and water flooding, are dependent on geology. The geology in the Gaza Strip is similar to that of a coastal plain, consisting of soft sandy soil in the upper layers and a harder bedrock in the deeper layers.
Geological materials are highly heterogeneous, meaning they consist of a varied and diverse mix of substances. Therefore, the results of an experiment at one point do not guarantee identical or even similar results at another point.
Apparently, the Gazans are well acquainted with their local geology and have constructed a complex network that optimally utilizes various layers. The long and narrow tunnels are located at intermediate depths, making them easier to dig. On the other hand, at greater depths, where it is more difficult to dig, there are well-protected and more covert centers that are challenging, if not impossible, to attack from the air.
Given the size of the Hamas network and the difficulty in destroying the underground infrastructure, some argue that it is a problem that cannot be effectively addressed. Indeed, it is difficult to imagine a scenario where Israel destroys hundreds of kilometers of Hamas tunnels.
This is a mission that requires enormous resources, financial, logistical, and others. 'In the end, they'll just dig it again, so what's the point?' is a response I've encountered in conversations with friends.
So, one could consider a middle-ground approach: Israel invests wise and targeted efforts to minimize the effectiveness of the tunnel network as much as possible.
Many original and innovative ideas have been raised in this context. From what I understand, solutions based on sealing are the most promising direction, as they are not dependent on geology and can likely guarantee desired outcomes with a higher probability. Moreover, they are less hazardous than the use of explosives, which can cause unintended harm to our own people.
As we know, there is an underground network of Hezbollah in the north as well. In 2019, Operation Northern Shield was launched, during which concrete contractors poured thousands of cubic meters of concrete to seal the tunnels, as reported in the media. Through this operation, the IDF succeeded in neutralizing years of offensive work and prevented a potential surprise attack in the north.
However, implementing a similar approach in the Gaza sector is not feasible or economically viable. It is not comparable to what happened in the north, where it was relatively safe to position on the Israeli side of the border, unlike in Gaza, where thousands of Palestinians reside in densely populated neighborhoods in a dangerous and threatening area.
From my understanding, there is a need to concentrate efforts on developing materials and methods for sealing Gaza tunnels. These materials would need to have suitable mechanical properties so that their breakdown would require significant efforts, akin to the efforts required for digging new tunnels.
Additionally, the implementation of these materials must be in accordance with the logistical and operational constraints, which only the military can define. Several factors could lead to a research competition resulting in the development of optimal solutions in this matter, where the best minds and resources would contribute to finding effective solutions.
By Dr. Amichai Mittelman, lecturer and researcher in the Department of Civil Engineering at Ariel University, specializing in civil engineering with a focus on tunnels. Dr. Mitttelman received advanced training at UBC in Canada through the Engineering and Construction Division in collaboration with the Ministry of Defense.
Guest author Dr. Amichai Mittelman, a lecturer at the Department of Civil Engineering at Ariel University, provides his insights
Photo: IDF Spokesperson's Unit
Since the dawn of humanity, people have always sought to exploit underground space for various purposes, including military uses. In this context, tunnels offer clear advantages in numerous aspects, particularly due to their being hidden structures and heavily fortified.
Tunnels have been used for offensive and defensive purposes in both World Wars and during the Cold War era. Israel, too, employs defensive use of underground infrastructure, and the bunker in the Kiriya military base is an excellent example of this.
In the years following World War II, the Americans conducted numerous experiments to assess the resilience of tunnels. They invested significant resources in these experiments and derived important conclusions from them.
These experiments were classified in the past, but today are declassified and available, and it is interesting and important to delve into the insights gained from them. Today, the magnificent tunnel network of the Viet Cong from the Vietnam War era stands and serves as a tourist site, a testament to the immense difficulty in destroying tunnels.
In short, a tunnel is a highly resilient structure against various threats. It is extremely difficult to cause a tunnel collapse through an explosion, requiring enormous amounts of explosives and ideal implementation. The explosion needs to be carried out in a way that causes the ceiling of the tunnel to collapse inward, thus blocking passage inside.
When detonating the tunnel within the airspace, the blast wave is expected to propagate and cause damage only to the immediate surroundings. Additionally, the likelihood of a blast within the tunnel's airspace causing a complete collapse of the tunnel is low.
Today, the State of Israel is facing an unprecedented military tunnel network in terms of its scope, which is notably more advanced than the Vietnamese network.
The media is talking about hundreds of kilometers and thousands of tunnels. While in the past, the central research effort was invested in developing means of detecting infiltrating tunnels, the advantages that these tunnels provide to the enemy on the battlefield require renewed readiness.
Contrary to explosions, another direction that has been attempted to deal with military tunnels is water flooding. Water resources are abundant, and Gaza's coastal location has prompted Egyptians to utilize this method in the past.
According to various reports, the IDF has also explored this direction during the current conflict. It is unclear what the results of this attempt were, but according to reports, the results were very limited and localized and did not lead to the desired outcome of neutralizing the threat.
It is also important to note that solutions based on the destruction of underground infrastructure, such as explosives and water flooding, are dependent on geology. The geology in the Gaza Strip is similar to that of a coastal plain, consisting of soft sandy soil in the upper layers and a harder bedrock in the deeper layers.
Geological materials are highly heterogeneous, meaning they consist of a varied and diverse mix of substances. Therefore, the results of an experiment at one point do not guarantee identical or even similar results at another point.
Apparently, the Gazans are well acquainted with their local geology and have constructed a complex network that optimally utilizes various layers. The long and narrow tunnels are located at intermediate depths, making them easier to dig. On the other hand, at greater depths, where it is more difficult to dig, there are well-protected and more covert centers that are challenging, if not impossible, to attack from the air.
Given the size of the Hamas network and the difficulty in destroying the underground infrastructure, some argue that it is a problem that cannot be effectively addressed. Indeed, it is difficult to imagine a scenario where Israel destroys hundreds of kilometers of Hamas tunnels.
This is a mission that requires enormous resources, financial, logistical, and others. 'In the end, they'll just dig it again, so what's the point?' is a response I've encountered in conversations with friends.
So, one could consider a middle-ground approach: Israel invests wise and targeted efforts to minimize the effectiveness of the tunnel network as much as possible.
Many original and innovative ideas have been raised in this context. From what I understand, solutions based on sealing are the most promising direction, as they are not dependent on geology and can likely guarantee desired outcomes with a higher probability. Moreover, they are less hazardous than the use of explosives, which can cause unintended harm to our own people.
As we know, there is an underground network of Hezbollah in the north as well. In 2019, Operation Northern Shield was launched, during which concrete contractors poured thousands of cubic meters of concrete to seal the tunnels, as reported in the media. Through this operation, the IDF succeeded in neutralizing years of offensive work and prevented a potential surprise attack in the north.
However, implementing a similar approach in the Gaza sector is not feasible or economically viable. It is not comparable to what happened in the north, where it was relatively safe to position on the Israeli side of the border, unlike in Gaza, where thousands of Palestinians reside in densely populated neighborhoods in a dangerous and threatening area.
From my understanding, there is a need to concentrate efforts on developing materials and methods for sealing Gaza tunnels. These materials would need to have suitable mechanical properties so that their breakdown would require significant efforts, akin to the efforts required for digging new tunnels.
Additionally, the implementation of these materials must be in accordance with the logistical and operational constraints, which only the military can define. Several factors could lead to a research competition resulting in the development of optimal solutions in this matter, where the best minds and resources would contribute to finding effective solutions.
By Dr. Amichai Mittelman, lecturer and researcher in the Department of Civil Engineering at Ariel University, specializing in civil engineering with a focus on tunnels. Dr. Mitttelman received advanced training at UBC in Canada through the Engineering and Construction Division in collaboration with the Ministry of Defense.
